[Federal Register Volume 76, Number 154 (Wednesday, August 10, 2011)]
[Rules and Regulations]
[Pages 49541-49567]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-19812]

[[Page 49541]]

Vol. 76


No. 154

August 10, 2011

Part II

Department of the Interior


Fish & Wildlife Services


50 CFR Part 17

Endangered and Threatened Wildlife and Plants; Emergency Listing of the 
Miami Blue Butterfly as Endangered, and Emergency Listing of the 
Cassius Blue, Ceraunus Blue, and Nickerbean Blue Butterflies as 
Threatened Due to Similarity of Appearance to the Miami Blue Butterfly; 
Final Rule

Federal Register / Vol. 76 , No. 154 / Wednesday, August 10, 2011 / 
Rules and Regulations

[[Page 49542]]



Fish and Wildlife Service

50 CFR Part 17

[Docket No. FWS-R4-ES-2011-0043 MO 92210-0-0008
RIN 1018-AX83

Endangered and Threatened Wildlife and Plants; Emergency Listing 
of the Miami Blue Butterfly as Endangered, and Emergency Listing of the 
Cassius Blue, Ceraunus Blue, and Nickerbean Blue Butterflies as 
Threatened Due to Similarity of Appearance to the Miami Blue Butterfly

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Emergency rule.


SUMMARY: We, the Fish and Wildlife Service (Service), exercise our 
authority pursuant to section 4(b)(7) of the Endangered Species Act of 
1973, as amended (Act), to emergency list the Miami blue butterfly 
(Cyclargus thomasi bethunebakeri) as endangered. This subspecies is 
currently known to occur at only a few small remote islands within the 
Florida Keys. Current population numbers are not known, but are 
estimated in the hundreds of butterflies. We are also emergency listing 
the cassius blue butterfly (Leptotes cassius theonus), ceraunus blue 
butterfly (Hemiargus ceraunus antibubastus), and nickerbean blue 
butterfly (Cyclargus ammon) as threatened due to similarity of 
appearance to the Miami blue, with a special rule pursuant to section 
4(d) of the Act.
    Due to the subspecies' severe reduction in geographic range, small 
population sizes, and imminent threats, we need to make protective 
measures afforded by the Act available to the Miami blue immediately. 
This emergency rule provides Federal protection pursuant to the Act for 
a period of 240 days. A proposed rule to list the Miami blue butterfly 
as endangered and to list the cassius blue butterfly, ceraunus blue 
butterfly, and nickerbean blue butterfly as threatened due to 
similarity of appearance to the Miami blue is published concurrently 
with this emergency rule, and it can be found in this issue of the 
Federal Register in the Proposed Rules section.

DATES: This emergency rule becomes effective on August 10, 2011, and 
expires April 6, 2012.

ADDRESSES: The supporting information used in this emergency rulemaking 
is available for inspection, by appointment, during normal business 
hours at the U.S. Fish and Wildlife Service, South Florida Ecological 
Services Office, 1339 20th Street, Vero Beach, Florida 32960-3559.

FOR FURTHER INFORMATION CONTACT: Paula Halupa, Fish and Wildlife 
Biologist, U.S. Fish and Wildlife Service, South Florida Ecological 
Services Office, 1339 20th Street, Vero Beach, Florida 32960-3559 by 
telephone 772-562-3909, ext. 257 or by electronic mail: 
[email protected].



    The Miami blue is a small, brightly colored butterfly approximately 
0.8 to 1.1 inches (1.9 to 2.9 centimeters [cm]) in length (Pyle 1981, 
p. 488) with a forewing length of 0.3 to 0.5 inches (8.0 to 12.5 
millimeters) (Minno and Emmel 1993, p. 134). Wings of males are blue 
above (dorsally), with a narrow black outer border and white fringes; 
females are bright blue dorsally, with black borders and an orange/red 
and black eyespot near the anal angle of the hindwing (Comstock and 
Huntington 1943, p. 98; Minno and Emmel 1993, p. 134). The underside is 
grayish with darker markings outlined with white and bands of white 
wedges near the outer margin. The ventral hindwing has two pairs of 
eyespots, one of which is capped with red; basal and costal spots on 
the hindwing are black and conspicuous (Minno and Emmel 1993, p. 134). 
The winter (dry season) form is much lighter blue than the summer (wet 
season) form and has narrow black borders (Opler and Krizek 1984, p. 
112). Seasonal wing pattern variation may be caused by changes in 
humidity, temperature, or length of day (Pyle 1981, p. 489). Miami blue 
larvae are bright green with a black head capsule, and pupae vary in 
color from black to brown (Minno and Emmel 1993, pp. 134-135).
    The Miami blue is similar in appearance to three other sympatric 
(occupying the same or overlapping geographic areas without 
interbreeding) butterflies that occur roughly in the same habitats: 
cassius blue (Leptotes cassius theonus), ceraunus blue (Hemiargus 
ceraunus antibubastus), and nickerbean blue (Cyclargus ammon). The 
Miami blue is slightly larger than the ceraunus blue (Minno and Emmel 
1993, p. 134), but the ceraunus blue has a different ventral pattern 
and flies close to the ground in open areas (Minno and Emmel 1994, p. 
647). The cassius blue often occurs with the Miami blue, but has dark 
bars rather than spots on the undersides of the wings (Minno and Emmel 
1994, p. 647). The Miami blue can be distinguished from the ceraunus 
blue and cassius blue by its very broad white ventral submarginal band, 
the dorsal turquoise color of both sexes, and the orange-capped 
marginal eyespot on the hind wings (Opler and Krizek 1984, p. 112). The 
nickerbean blue is also similar to the Miami blue in general appearance 
but is considerably smaller; it has three black spots across the basal 
hindwing, while the Miami blue has four (Calhoun et al. 2002, p. 15). 
The larvae and pupae of the nickerbean blue closely resemble the Miami 
blue (Calhoun et al. 2002, p. 15).
    In a comparison of Miami blue butterfly specimens within the 
Florida Museum of Natural History (FLMNH) collection, Saarinen (2009, 
pp. 42-43) found a significant difference in wing chord length between 
males and females, with males having shorter wing chords than females. 
However, no significant differences were found between wing chord 
length in comparing wet and dry seasons, decade of collection, seven 
different regions, or between eastern mainland and Keys specimens 
(Saarinen 2009, pp. 42-43). No seasonal size differences were found 
between the mainland populations and those in the Keys (Saarinen 2009, 
p. 43).
    In a comparison of body size in a recent Miami blue population 
(BHSP 2002-2006), females were significantly larger than males, and 
individuals sampled in the wet season were also significantly larger 
than in the dry season (Saarinen 2009, p. 43). In a comparison of 
recent Bahia Honda State Park (BHSP) individuals with specimens from 
historical collections (FLMNH data), BHSP individuals were 
significantly larger than historical specimens, females from BHSP were 
also significantly larger than historical female specimens, and BHSP 
adults measured in wet seasons were larger than those sampled in wet 
seasons in museum collections (Saarinen 2009, p. 43). Saarinen (2009, 
p. 47) suggested that perhaps larger adults were selected for over time 
with larger adults being more capable of dispersing and finding food 
and mates. Limited food resources during larval development or abrupt 
termination of availability of food in the last larval instar can lead 
to early pupation and a smaller adult size (T.C. Emmel, pers. comm., as 
cited in Saarinen 2009, p. 47). It is possible that differences in host 
plant (e.g., nutrition) and age of specimens (e.g., freshness) may also 
be factors when comparing body size between recent specimens and those 
from historical collections.

[[Page 49543]]


    The Miami blue belongs to the family Lycaenidae (Leach), subfamily 
Polyommatinae (Swainson). The species Hemiargus thomasi was originally 
described by Clench (1941, pp. 407-408), and the subspecies Hemiargus 
thomasi bethunebakeri was first described by Comstock and Huntington 
(1943, p. 97). Although some authors continue to use Hemiargus, Nabokov 
(1945, p. 14) instituted Cyclargus for some species, which has been 
supported by more recent research (Johnson and Balint 1995, pp. 1-3, 8-
11, 13; Calhoun et al. 2002, p. 13; K. Johnson, Florida State 
Collection of Arthropods, in litt. 2002). There are differences in the 
internal genitalic structures of the genera Hemiargus and Cyclargus 
(Johnson and Balint 1995, pp. 2-3, 11; K. Johnson, in litt. 2002). Kurt 
Johnson (in litt. 2002), who has published most of the existing 
literature since 1950 on the blue butterflies of the tribe 
Polyommatini, reaffirmed that thomasi belongs in the genus Cyclargus 
(Nabokov 1945, p. 14), not Hemiargus. Accordingly, Cyclargus thomasi 
bethunebakeri (Pelham 2008, p. 256) and its taxonomic standing is 
accepted (Integrated Taxonomic Information System 2011, p. 1).
    In 2003, questions about the taxonomic identity of Miami blues from 
BHSP were raised by a few individuals. To address these questions, the 
Service sent two pairs (male and female) of adult specimens to three 
independent taxonomists/reviewers (Dr. Jacqueline Miller, Associate 
Curator, Allyn Museum of Entomology (AME), FLMNH; Dr. Paul Opler, 
Colorado State University; and John Calhoun, Museum of Entomology, 
Florida State Collection of Arthropods) for verification. To avoid harm 
to the wild population, scientists examined moribund adults from a 
captive colony generated from individuals taken from BHSP. Each 
reviewer independently confirmed through various means (e.g., 
comparison with confirmed specimens, dissection and examination of 
genitalia) that the identities of the adult specimens examined were 
Cyclargus thomasi bethunebakeri (J. Miller, in litt. 2003; P. Opler, in 
litt. 2003; J. Calhoun, in litt. 2003a). We received an additional 
confirmation from Lee Miller, Curator (AME, FLMNH) stating that the 
identities of the adult specimens examined were Cyclargus thomasi 
bethunebakeri (L. Miller, in litt. 2003). Taxonomic verification by 
genitalic dissection of the Miami blue at Key West National Wildlife 
Refuge (KWNWR) has not occurred, but preliminary molecular evidence has 
confirmed that they are the same taxon (E.V. Saarinen, unpub. data, as 
cited in Saarinen 2009, p. 18).

Life History

    Like all butterflies, the Miami blue undergoes complete 
metamorphosis, with four life stages (egg, caterpillar or larva, pupa 
or chrysalis, and adult). The generation time is approximately 30-40 
days (Carroll and Loye 2006, p. 19; Saarinen 2009, p. 22, 76). Although 
a single Miami blue female can lay 300 eggs, high mortality may occur 
in the immature larval stages prior to adulthood (T. Emmel, University 
of Florida [UF], pers. comm. 2002). Reported host plants are blackbead 
(Pithecellobium spp.), nickerbean (Caesalpinia spp.), balloonvine 
(Cardiospermum spp.), and presumably Acacia spp. (Kimball 1965, p. 49; 
Lenczewski 1980, p. 47; Pyle 1981, p. 489; Opler and Krizek 1984, p. 
113; Minno and Emmel 1993, p. 134; Calhoun et al. 2002, p. 18; Cannon 
et al. 2010, p. 851). In addition, Rutkowski (1971, p. 137) observed a 
female laying one egg just above the lateral bud on snowberry 
(Chiococca alba). Eggs are laid singly near the base of young pods or 
just above the lateral buds of balloonvine and the flowers of 
leguminous trees (Opler and Krizek 1984, p. 113; Minno and Emmel 1993, 
p. 134); flower buds and young tender leaves of legumes are preferred 
(Minno and Minno 2009, p. 78; M. Minno, pers. comm. 2010).
    On nickerbean (Caesalpinia spp.), females lay eggs on developing 
shoots, foliage, and flower buds (Saarinen 2009, p. 22). Oviposition 
occurs throughout the day with females often seeking terminal growth 
close to the ground (< 3.3 feet [< 1 meter]) or in locations sheltered 
from the wind (Emmel and Daniels 2004, p. 13). Eggs are generally laid 
singly, but may be clustered on developing leaves, shoot tips, and 
flower buds (Saarinen 2009, p. 22). After several days of development, 
larvae chew out of eggs and develop through four instar stages, with 
total larval development time lasting 3 to 4 weeks, depending upon 
temperature and humidity (Saarinen 2009, p. 22). Fourth instar larvae 
pupate in sheltered or inconspicuous areas, often underneath leaf 
whorls or bracts (Saarinen 2009, p. 22). Adult butterflies eclose 
(emerge) after 5 to 8 days, depending on temperature and humidity 
(Saarinen 2009, p. 22).
    On blackbead plants, females lay eggs on flower buds and emerging 
leaves (Cannon et al. 2010, p. 851). Oviposition on, or larval 
consumption of, mature blackbead leaves was not observed (Cannon et al. 
2010, p. 851). Thus, Cannon et al. (2010, p. 851) suggest that 
abundance may be limited by the availability of young blackbead leaves 
and buds for egg-laying, even if abundant suitable nectar sources (see 
Habitat) are available year-round.
    On balloonvine, females lay single eggs near fruit (capsules) 
(Carroll and Loye 2006, p. 18). Newly hatched larvae chew distinctive 
holes through the outer walls of the capsules to access seeds (Minno 
and Emmel 1993, p. 134). After consuming seeds within the natal 
capsule, larvae must crawl to a sequence of two or three balloons 
before growing large enough to pupate. Attending ants follow through 
the same holes (see Interspecific relationships below). Miami blues 
were also observed to commonly pupate within mature capsules (sometimes 
with ants in attendance within the capsule) (Carroll and Loye 2006, p. 
    The Miami blue has been described as having multiple, overlapping 
broods year-round (Pyle 1981, p. 489). Adults can be found every month 
of the year (Opler and Krizek 1984, pp. 112-113; Minno and Emmel 1993, 
p. 135; 1994, p. 647; Emmel and Daniels 2004, p. 9; Saarinen 2009, p. 
22). Opler and Krizek (1984, pp. 112-113) indicated one long winter 
generation from December to April, during which time the adults are 
probably in reproductive diapause (a period in which growth, 
development, and physiological activity is suspended or diminished); a 
succession of shorter generations was thought to occur from May through 
November, the exact number of which is unknown. Glassberg et al. (2000, 
p. 79) described the Miami blue as having occurred all year, with three 
or more broods. Researchers have noted a marked decrease of adults from 
December to early February at BHSP, indicative of a short diapause 
(Emmel and Daniels 2003, p. 3; 2004, p. 9). Saarinen also noted that 
the life cycle at BHSP slowed in winter months and suspected a slight 
diapause (E.V. Saarinen and J.C. Daniels, unpub. data, as cited in 
Saarinen 2009, p. 22). Conversely, Minno (pers. comm. 2010) notes that 
there have been records of adults in December and January and suggests 
that this tropical butterfly may not have a winter diapause, but 
rather, emergence may be delayed by cold temperatures in some years. 
Salvato and Salvato (2007, p. 163) and Cannon et al. (2010, pp. 849-
850) also reported numerous adults at BHSP and KWNWR, respectively, 
during winter months.
    Information on adult lifespan is limited. Adults may live a maximum 
of 9 days, but most adults live only a few

[[Page 49544]]

days (J. Daniels, UF, pers. comm. 2003a, 2003b). In general, adult 
butterflies survive less than a week in the wild; there are 
approximately 8-10 generations per year (Saarinen et al. 2009a, p. 31). 
Generations are not completely discrete due to the variance in 
development time of all life stages (Saarinen et al. 2009a, p. 31).
    Range size and dispersal--Adult Miami blues are nonmigratory and 
appear to be very sedentary (Emmel and Daniels 2004, p. 6). Based on 
mark-recapture work conducted in 2002-2003, recaptured adults (N=39) 
moved an average of 6.53 +/- 11.68 feet (2.0 +[sol]- 3.6 meters), four 
individuals moved between 25 and 50 feet (7.6 and 15.2 meters), and 
only three individuals moved more than 50 feet (15.2 meters) over a few 
days (Emmel and Daniels 2004, pp. 6, 32-38). Few individuals were found 
to move between the lower and upper walkway locations of the south end 
colony sites at BHSP (approximately 100 feet [30.5 meters]); no 
movement between any of the smaller individual, isolated colony sites 
was recorded (Emmel and Daniels 2004, p. 6). However, Saarinen (2009, 
pp. 73, 78-79) found that genetic exchange between colonies occurred at 
BHSP and noted that small habitat patches may be crucial in providing 
links between subpopulations in an area.
    Interspecific relationships--As in many lycaenids worldwide (Pierce 
et al. 2002, p. 734), Miami blue larvae associate with ants (Emmel 
1991, p. 13; Minno and Emmel 1993, p. 135; Carroll and Loye 2006, pp. 
19-20) in at least four genera of ants in three subfamilies of 
Formicidae (Saarinen and Daniels 2006, p. 71; Saarinen 2009, p. 131, 
133). Miami blues using nickerbean at BHSP and Everglades National Park 
(ENP) (reintroduced individuals) were variously tended by Camponotus 
floridanus, C. planatus, Crematogaster ashmeadi, Forelius pruinosus, 
and Tapinoma melanocephalum (Saarinen and Daniels 2006, p. 71; Saarinen 
2009, pp. 131, 138). C. floridanus was the primary ant symbiont, 
commonly found tending larvae; other ant species were encountered less 
often (Saarinen and Daniels 2006, p. 70; Saarinen 2009, pp. 131-132). 
Liquid (honeydew) exuded from the butterfly's dorsal nectary organ 
(honey gland) was actively imbibed by all species of ants (Saarinen and 
Daniels 2006, p. 70; Saarinen 2009, p. 132).
    Late Miami blue instars were always found in association with ants, 
but early instars, prepupae, and pupae were frequently found without 
ants present (Saarinen and Daniels 2006, p. 70). Forelius pruinosus and 
Tapinoma melanocephalum were observed to derive honeydew from Miami 
blues they tended, but were not observed to actively protect them from 
any predator (Saarinen and Daniels 2006, p. 71; Saarinen 2009, p. 133). 
However, the presence of ants in the vicinity of larvae may potentially 
deter predators (Saarinen and Daniels 2006, pp. 71, 73; Saarinen 2009, 
p. 133, Trager and Daniels 2009, p. 480). Two additional ants, 
Paratrechina longicornis and P. bourbonica, have been identified as 
potential associates of the Miami blue (Saarinen and Daniels 2006, pp. 
70-71; Saarinen 2009, pp. 131, 138). P. longicornis was found near 
Miami blue larvae and appeared to tend them during brief encounters; P. 
bourbonica tended another lycaenid, martial scrub-hairstreak (Strymon 
martialis) at BHSP (Saarinen and Daniels 2006, p. 70). Cannon et al. 
(2007, p. 16) also observed two ant species attending Miami blues on 
KWNWR. Based on photographs, the ants appeared to be C. inaequalis and 
P. longicornis. C. planatus was observed on blackbead.
    In the 1980s, Miami blue larvae that fed on balloonvine in the 
upper Keys were also tended by ants (C. floridanus and C. planatus) 
(Carroll and Loye 2006, pp. 19-20). Carroll and Loye (2006, p. 20) 
found that Camponotus spp. raised with Miami blue larvae lived longer 
than ants raised with larvae of other lycaenid species or without any 
food source, demonstrating that larval secretions benefit ants.
    More recently, Trager and Daniels (2009, p. 479) most commonly 
found C. floridanus and C. planatus associated with wild and recently 
released Miami blue larvae. In a comparison of Miami blue larvae raised 
with and without ants, no effect of ant presence was found on any 
measurements of larval performance (e.g., age at pupation, pupal mass, 
length of pupation, total time as an immature) (Trager and Daniels 
2009, p. 480). Miami blue larval development was found to be similar to 
that of other conspecific lycaenid species not tended by ants (Trager 
and Daniels 2009, p. 480). Although the relationships are not 
completely understood, it appears that Miami blue larvae may receive 
some benefits from tending ants (e.g., potential defense from 
predators) without much, if any, costs incurred.


    The Miami blue is a coastal butterfly reported to occur in openings 
and around the edges of hardwood hammocks (forest habitats 
characterized by broad-leaved evergreens), and in other communities 
adjacent to the coast that are prone to frequent natural disturbances 
(e.g., coastal berm hammocks, dunes, and scrub) (Opler and Krizek 1984, 
p. 112; Minno and Emmel 1994, p. 647; Emmel and Daniels 2004, p. 12). 
It also uses tropical pinelands (Minno and Emmel 1993, p. 134) and open 
sunny areas along trails (Pyle 1981, p. 489). In the Keys, it was most 
abundant near disturbed hammocks where weedy flowers provided nectar 
(Minno and Emmel 1994, p. 647). It also occurred in pine rocklands 
(fire-dependent slash pine community with palms and a grassy 
understory) on Big Pine Key (Minno and Emmel 1993, p. 134; Calhoun et 
al. 2002, p. 18) and elsewhere in Monroe and Miami-Dade Counties. In 
Miami-Dade County, it occurred locally inland, sometimes in abundance 
(M. Minno, pers. comm. 2010). Within KWNWR, all occupied areas had 
coastal strands and dunes fronted by beaches (Cannon et al. 2007, p. 
13; Cannon et al. 2010, p. 851).
    Larval host plants include blackbead, nickerbean, balloonvine, and 
presumably Acacia spp. (Dyar 1900, pp. 448-449, Kimball 1965, p. 49; 
Lenczewski 1980, p. 47; Pyle 1981, p. 489; Calhoun et al. 2002, p. 18). 
Gray nickerbean (Caesalpinia bonduc) is widespread and common in 
coastal south Florida. Following disturbances, it can dominate large 
areas (K. Bradley, The Institute for Regional Conservation [IRC], pers. 
comm. 2002). Gray nickerbean has been recorded as far north as Volusia 
County on the east coast, matching the historical range of the Miami 
blue, and Levy County on the west coast (J. Calhoun, pers. comm. 
2003b). The Miami blue is also reported to use peacock flower 
(Caesalpinia pulcherrima) (Matteson 1930, pp. 13-14; Calhoun et al. 
2002, p. 18), a widely cultivated exotic that occurs in disturbed 
uplands and gardens (Gann et al. 2001-2010, p. 1). Rutkowski (1971, p. 
137) and Opler and Krizek (1984, p. 113) reported the use of snowberry. 
Brewer (1982, p. 22) reported the use of cat's paw blackbead 
(Pithecellobium unguis-cati) on Sanibel Island in Lee County.
    Prior to the 1970s, documented host plants for the butterfly were 
nickerbean and blackbead (J. Calhoun, pers. comm. 2003b). Balloonvine 
(Cardiospermum spp.) was not reported as a host plant until the 1970s, 
when these plants seemed to have become common in extreme southern 
Florida (J. Calhoun, pers. comm. 2003b). Subsequently, balloonvine 
(Cardiospermum halicacabum), an exotic species in Florida, was the most 
frequently reported host plant for Miami blue (e.g., Lenczewski 1980, 
p. 47; Opler and Krizek 1984, p. 113; Minno and Emmel

[[Page 49545]]

1993, p. 134; 1994, p. 647; Calhoun et al. 2002, p. 18). However, 
Carroll and Loye (2006, pp. 13-15) corrected ``the common view that a 
principal host plant, balloonvine, is an exotic weed.'' They found that 
published reports of Miami blue larvae on balloonvine all identified 
the host as C. halicacabum and stated that the butterfly was instead 
dependent upon a declining native C. corindum (Carroll and Loye 2006, 
pp. 14, 23). Bradley (pers. comm. 2002) also confirmed that C. 
halicacabum does not occur in the Keys, noting that the native 
balloonvine (C. corindum) is relatively common and widespread in the 
Keys and has been commonly mistaken as C. halicacabum in the Keys and 
other sites in south Florida.
    Calhoun (pers. comm. 2003b) suggested that the Miami blue may 
simply utilize whatever acceptable hosts are available under suitable 
conditions. According to Calhoun (pers. comm. 2003b), a review of the 
historical range of the butterfly and its host plants suggests 
balloonvine was a more recent larval host plant and temporarily 
surpassed nickerbean as the primary host plant. As native coastal 
habitats were destroyed, balloonvine readily invaded disturbed 
environments, and the Miami blue used what was most commonly available. 
Minno (pers. comm. 2010) suggested that the Miami blue used balloonvine 
on Key Largo and Plantation Key extensively in the 1970s through the 
1990s, noting that nickerbean, blackbead, and perhaps other hosts were 
also probably used, but not documented.
    The Miami blue metapopulation (series of small populations that 
have some level of interaction) at KWNWR was found to rely upon Florida 
Keys blackbead as the singular host plant (Cannon et al. 2007, p. 1; 
Cannon et al. 2010, pp. 851-852). Blackbead was also an important 
nectar plant when in flower. High counts of Miami blues at KWNWR were 
generally associated with the emergence of flowers and new leaves on 
blackbead (Cannon et al. 2007, pp. 14-15; Cannon et al. 2010, pp. 851-
852). All sites that supported Miami blues contained blackbead (Cannon 
et al. 2007, p. 6; Cannon et al. 2010, p. 851). Limited abundance of 
blackbead within select areas of KWNWR was thought to limit abundance 
of the Miami blue (Cannon et al. 2007, p. 10; Cannon et al. 2010, p. 
850). At BHSP, the Miami blue was closely associated with gray 
nickerbean, but also uses blackbead (M. Minno, pers. comm. 2010). In 
KWNWR, gray nickerbean was rare, with only a few small plants on Boca 
Grande Key and the Marquesas Keys (Cannon et al. 2010, p. 851).
    Adult Miami blues have been reported to feed on a wide variety of 
nectar sources including Spanish needles (Bidens alba), Leavenworth's 
tickseed (Coreopsis leavenworthi), scorpionstail (Heliotropium 
angiospermum), turkey tangle fogfruit or capeweed (Lippia nodiflora), 
buttonsage (Lantana involucrata), snow squarestem (Melanthera nivea [M. 
aspera]), blackbead, Brazilian pepper (Schinus terebinthifolius), false 
buttonweed (Spermacoce spp.), and seaside heliotrope (Heliotropium 
curassavicum) (Pyle 1981, p. 489; Opler and Krizek 1984, p. 113; Minno 
and Emmel 1993, p. 135; Emmel and Daniels 2004, p. 12). Emmel and 
Daniels (2004, p. 12) reported that the Miami blue uses a variety of 
flowering plant species in the Boraginaceae, Asteraceae, Fabaceae, 
Polygonaceae, and Verbenaceae families for nectar. Cannon et al. (2010, 
p. 851) found the butterfly uses nine plant species as nectar sources 
within KWNWR, including: Blackbead, snow squarestem, coastal searocket 
(Cakile lanceolata), black torch (Erithalis fruticosa), yellow joyweed 
(Alternanthera flavescens), bay cedar (Suriana maritime), sea lavender 
(Argusia gnaphalodes), seaside heliotrope, and sea purslane (Sesuvium 
    Nectar sources must be near potential host plants since the 
butterflies are sedentary and may not travel between patches of host 
and nectar sources (Emmel and Daniels 2004, p. 13). This may help 
explain the absence of the Miami blue from areas in which host plants 
are abundant and nectar sources are limited (J. Calhoun, pers. comm. 
2003b). Emmel and Daniels (2004, p. 13) argued that it is potentially 
critical that sufficient available adult nectar sources be directly 
adjacent to host patches and also important that a range of potential 
nectar sources be available in the event one plant species goes out of 
flower or is adversely impacted by environmental factors. Cannon et al. 
(2010, p. 851) suggested that the growth stage of blackbead, coupled 
with abundant nectar from herbaceous plants, likely influenced Miami 
blue abundance; the highest counts occurred when blackbead was 
flowering profusely and producing new leaves.

Historical Distribution

    The Miami blue butterfly (Cyclargus thomasi bethunebakeri) is 
endemic to Florida with additional subspecies occurring in the Bahamas, 
Puerto Rico, and Hispaniola (Smith et al. 1994, p. 129; Hernandez 2004, 
p. 100; Saarinen 2009, pp. 18-19, 28). Field guides and other sources 
differ as to whether C. thomasi bethunebakeri occurs in the Bahamas. 
Clench (1963, p. 250), who collected butterflies extensively in the 
West Indies, indicated that the subspecies occurred only in Florida. 
Riley (1975, p. 110) and Calhoun et al. (2002, p. 13) indicated that 
the Miami blue of Florida rarely occurs as a stray in the Bahamas. 
Minno and Emmel (1993, p. 134; 1994, p. 647) and Calhoun (1997, p. 46) 
considered the Miami blue to occur only in Florida (endemic to Florida, 
with other subspecies found in the Bahamas and Greater Antilles). Smith 
et al. (1994, p. 129) indicated that the Miami blue occurs in southern 
Florida, but noted it has been recorded from the Bimini Islands in the 
Bahamas. However, in a recent comprehensive study of museum specimens, 
Saarinen (2009, p. 28) found no specimens in current museum holdings to 
verify this. Overall, the majority of historical records pertaining to 
this subspecies' distribution are dominated by Florida occurrences, 
with any peripheral occurrences in the Bahamas possibly being ephemeral 
in nature.
    Although information on distribution is somewhat limited, it is 
clear that the historical range of the Miami blue has been 
significantly reduced. The type series (i.e., the original set of 
specimens on which the description of the species is based) contains 
specimens ranging from Key West up the east coast to Volusia County 
(Comstock and Huntington 1943, p. 98; J. Calhoun, pers. comm., 2003b). 
Opler and Krizek (1984, p. 112) showed its historical range as being 
approximately from Tampa Bay and Cape Canaveral southward along the 
coasts and through the Keys. It has also been collected in the Dry 
Tortugas (Forbes 1941, pp. 147-148; Kimball 1965, p. 49; Glassberg and 
Salvato 2000, p. 2). Lenczewski (1980, p. 47) noted that it was 
reported as extremely common in the Miami area in the 1930s and 1940s. 
Calhoun et al. (2002, p. 17) placed the historical limits of the 
subspecies' northern distribution at Hillsborough and Volusia Counties, 
extending southward along the coasts to the Marquesas Keys (west of Key 
    The Miami blue was most common on the southern mainland and the 
Keys, especially Key Largo and Big Pine Key (Calhoun et al. 2002, p. 
17) and other larger keys with hardwood hammock (Monroe County) (M. 
Minno, pers. comm. 2010). The subspecies was recorded on at least 10 
islands of the Keys (Adams Key, Big Pine Key, Elliott Key, Geiger Key, 
Key Largo, Lignumvitae Key, Old Rhodes Key, Plantation Key, Stock 
Island, Sugarloaf Key) (Minno and Emmel 1993, p. 134). On the Gulf 
coast, it was reportedly

[[Page 49546]]

more localized and tended to occur on more southerly barrier islands 
(J. Calhoun, pers. comm. 2003b). According to Calhoun et al. (2002, p. 
17), the Miami blue occupied areas on the barrier islands of Sanibel, 
Marco, and Chokoloskee, along the west coast into the 1980s (based upon 
Brewer 1982, p. 22; Minno and Emmel 1994, pp. 647-648). Lenczewski 
(1980, p. 47) reported that the Miami blue historically occurred at 
Chokoloskee, Royal Palm (Miami-Dade County), and Flamingo (Monroe 
County) within ENP, but that the subspecies has not been observed in 
ENP since 1972.
    Based upon examination of specimens from museum collections 
(N=689), Saarinen (2009, pp. 42, 55-57) found a large, primarily 
coastal, geographic distribution for the butterfly. Most specimens from 
an 11-county area from 1900 to 1990 were collected in Miami-Dade and 
Monroe Counties (Saarinen 2009, pp. 42, 58). Records from Miami-Dade 
County (N=212) were most numerous in the 1930s and 1940s; records from 
Monroe County (N=387) (including all of the Florida Keys) were most 
numerous in the 1970s (Saarinen 2009, pp. 42, 58). Saarinen (2009, p. 
47) was not able to quantify issues of collector bias and noted that 
collecting restrictions, inaccessibility of certain islands, and 
targeted interest in certain areas, may have been factors influencing 
the relative abundance (and distribution) of specimens collected. For 
example, it is unclear whether Key Largo represented a ``central 
hotspot,'' a spot simply heavily visited by lepidopterists, or both 
(Saarinen 2009, p. 47). Still, it is clear that specimens were common 
in museum collections from the early 1900s to the 1980s, suggesting 
that the butterfly was abundant, at least in local patches, during this 
time period (Saarinen 2009, p. 46). This is consistent with the work of 
Carroll and Loye (2006, pp. 15-18), who, in a compilation of location 
data for specimens (N=209), found that most collections were from the 
Upper Keys; those from peripheral sites were generally less recent and 
only single specimens. Examination of museum records further verified 
the Miami blue's wide distribution in southern Florida through time 
(Carroll and Loye 2006, pp. 15-18; Saarinen 2009, p. 46).
    By the 1990s, very few Miami blue populations were known to 
persist, and the butterfly had not been seen on the western Florida 
coast since 1990, where it was last recorded on Sanibel Island (Calhoun 
et al. 2002, p. 17). One of the few verifiable reports (prior to 
rediscovery in 1999) was on Big Pine Key in March 1992 (Glassberg et 
al. 2000, p. 79; Glassberg and Salvato 2000, p. 1; Calhoun et al. 2002, 
p. 17). Following Hurricane Andrew in 1992, there were a few 
unsupported reports from Key Largo and Big Pine Key and the 
southeastern Florida mainland from approximately 1993 to 1998 
(Glassberg and Salvato 2000, p. 3; Calhoun et al. 2002, p. 17). In 
1996, four adult Miami blues were observed in the area of Dagny Johnson 
Key Largo Hammock Botanical State Park (DJSP) by Linda and Byrum Cooper 
(L. Cooper, listowner of LEPSrUS Web site, pers. comm. 2002; Calhoun et 
al. 2002, p. 17). However, a habitat restoration project apparently 
eradicated that population (L. Cooper, pers. comm. as cited in Calhoun 
et al. 2002, p. 17).
    The Miami blue was presumed to be extirpated until its rediscovery 
in 1999 by Jane Ruffin, who observed approximately 50 individuals at a 
site in the lower Keys (Bahia Honda) (Ruffin and Glassberg 2000, p. 3; 
Calhoun et al. 2002, p. 17). Additional individuals were located at a 
site within 0.5 mile (0.8 kilometers (km)) of where Ruffin had 
discovered the population (Glassberg and Salvato 2000, p. 3). Glassberg 
and Salvato (2000, p. 1) stated that more than 15 highly competent 
butterfly enthusiasts had failed to find any populations of the Miami 
blue from 1992 until 1999, despite more than 1,000 hours of search 
effort in all sites known to harbor former colonies and other potential 
sites throughout south Florida and the Keys. In May 2001, there was an 
additional sighting by Richard Gillmore of a single Miami blue in the 
hammocks in North Key Largo (Calhoun et al. 2002, p. 17; J. Calhoun, 
pers. comm. 2003b).

Current Distribution

    Numerous searches for the Miami blue have occurred in the past 
decade by various parties. The Miami blue was not observed on 105 
survey dates at 11 locations on the southern Florida mainland from 1990 
to 2002 (Edwards and Glassberg 2002, p. 4). In the Keys, surveys during 
the same time period also produced no sightings of the Miami blue at 29 
locations for 224 survey dates (Edwards and Glassberg 2002, p. 4). In 
2002, the Service initiated a status survey, contracting researchers at 
the UF, to search areas within the subspecies' historical range, 
concentrating on the extreme south Florida mainland and throughout the 
Keys. Despite surveys at 45 sites during 2002-2003, adults or immature 
stages were found only at a single site near BHSP on West Summerland 
Key (Emmel and Daniels 2004, pp. 3-6; 21-25) (approximately 1.9 miles 
[3 km] west of BHSP). The Miami blue was not found on the mainland, 
including Fakahatchee Strand, Charles Deering Estate, ENP, Marco 
Island, or Chokoloskee (Emmel and Daniels 2004, pp. 5-6, 25). It was 
also absent from the following locations in the Keys: Elliott, Old 
Rhodes, Totten, and Adams Key in Biscayne National Park (BNP) and Key 
Largo and Plantation Key in the Upper Keys; Lignumvitae, Lower 
Matecumbe, Indian, and Long Keys in the Middle Keys; and Little Duck, 
Missouri, Ohio, No Name, Big Pine, Ramrod, Little Torch, Wahoo, Cudjoe, 
Sugarloaf, and Stock Island in the Lower Keys (Emmel and Daniels 2004, 
pp. 3-5; 21-24).
    Based upon an additional independent survey in 2002, the Miami blue 
was also not found at 18 historical locations where it had previously 
been observed or collected in Monroe, Broward, Miami-Dade, and Collier 
Counties into the 1980s (D. Fine, unpub. data, pers. comm. 2002). These 
were: Cactus Hammock (Big Pine Key), County Road (Big Pine Key), Grassy 
Key, John Pennekamp Coral Reef State Park, Windley Key, Crawl Key, 
Stock Island, Plantation Key, and Lower Matecumbe Key in Monroe County; 
Hugh Taylor Birch State Park and Coral Springs in Broward County; 
Redlands, IFAS Station, Frog City, and Card Sound Road in Miami-Dade 
County; Marco Island and Fakahatchee Strand State Preserve in Collier 
    In 2003, the Service contracted the North American Butterfly 
Association (NABA) to perform systematic surveys in south Florida and 
the Keys to identify all sites at which 21 targeted butterflies, 
including the Miami blue, could be found. Despite considerable survey 
effort (i.e., 187 surveys performed), the Miami blue was not located at 
any location except Bahia Honda (NABA 2005, pp. 1-7). In addition, the 
Miami blue was not present within the J.N. Ding Darling National 
Wildlife Refuge or on Sanibel-Captiva Conservation Foundation 
properties (both on Sanibel Island), during annual surveys conducted 
from 1998 to 2009 (M. Salvato, pers. comm. 2011a). Monthly or quarterly 
surveys of Big Pine Key, conducted from 1997 to 2010, failed to locate 
Miami blues (M. Salvato, pers. comm. 2011b). Minno and Minno (2009, pp. 
77, 123-193) failed to locate the subspecies during butterfly surveys 
throughout the Keys conducted from August 2006 to July 2009.
    Although two fifth-instar larvae were documented on West Summerland 
Key in November 2003, on unprotected land approximately 2.2 miles (3.6 
km) west of BHSP (Emmel and Daniels 2004, pp. 3, 24, 26), none have 
been seen there

[[Page 49547]]

since. According to Daniels (pers. comm. 2003c), an adult (or adults) 
was likely blown to this key from Bahia Honda by strong winds or was at 
least partially assisted by the wind.
    In November 2006, Miami blues were discovered on islands within 
KWNWR (Cannon et al. 2007, p. 2). This discovery was significant 
because it was a new, geographically separate population, and doubled 
the known number of metapopulations remaining (to 2). During the period 
from 1999 to 2009, the Miami blue was consistently found at BHSP 
(Ruffin and Glassberg 2000, p. 29; Edwards and Glassberg 2002, p. 9; 
Emmel and Daniels 2009, p. 4; Daniels 2009, p. 3). However, this 
population may now be extirpated. This leaves the islands within KWNWR 
as the only known locations of the subspecies.
    Overall, the Miami blue has undergone a substantial reduction in 
its historical range, with an estimated > 99 percent decline in area 
occupied (Florida Fish and Wildlife Conservation Commission [FWC] 2010, 
p. 11). In 2009, metapopulations existed at two main locations: BHSP 
and KWNWR, roughly 50 miles (80 km) apart. The metapopulation at BHSP 
is now possibly extirpated with the last adult documented in July 2010 
(A. Edwards, Florida Atlantic University, pers. comm. 2011). It is 
feasible that additional occurrences exist in the Keys, but these may 
be ephemeral and low in population number (Saarinen 2009, p. 143). In 
2010, the Service funded an additional study with UF to search remote 
areas for possible presence; this study is now underway. The subspecies 
was not located in limited surveys conducted in the Cape Sable area of 
ENP in March 2011 (P. Halupa, pers. obs. 2011; M. Minno, pers. comm. 

Bahia Honda State Park

    Bahia Honda is a small island at the east end of the lower Keys, 
approximately 7.0 miles (11.3 km) west of Vaca Key (Marathon) and 2.0 
miles (3.2 km) east of Big Pine Key. The amount of suitable habitat 
(habitat supporting larval host plants and adjacent adult nectar 
sources) within BHSP is approximately 1.5 acres (0.6 hectares [ha]). Of 
the suitable habitat available at BHSP, approximately 85 percent (1.3 
acres [0.5 ha]) was occupied by the Miami blue (Emmel and Daniels 2004, 
p. 12). The metapopulation comprised 13 distinct colonies, with the 
core comprising 3 or 4 colonies, located at the southwest end (Emmel 
and Daniels 2004, pp. 6, 27). This area contained the largest 
contiguous patch of host plants, although the size was estimated to be 
0.8 acres (0.32 ha) (Emmel and Daniels 2004, p. 12). The second largest 
colony occurred at the opposite (northeast) end of BHSP and was based 
solely on the presence of two to three small, isolated patches of 
nickerbean directly adjacent to an existing nature trail and parking 
area (Emmel and Daniels 2004, p. 6). The remaining colonies were 
isolated, with most occurring in close proximity to the main park road 
(Emmel and Daniels 2004, pp. 13, 27). Isolated colonies used very small 
patches of nickerbean (e.g., one was estimated to be 10 by 10 feet [3 
by 3 meters]) (Emmel and Daniels 2003, p. 3), often adjacent to paved 
roads (Emmel and Daniels 2004, pp. 6, 12, 27).

Key West National Wildlife Refuge

    Efforts to define the limits of the KWNWR metapopulation were 
conducted from November 2006 to July 2007 (Cannon et al. 2007, pp. 10-
11; 2010, p. 849). Miami blues were found in seven sites on five 
islands in the Marquesas Keys, approximately 12.2 miles (19.6 km) west 
of Key West, and on Boca Grande Key, approximately 11.8 miles (19 km) 
west of Key West (6.3 miles [10.1 km] east-southeast of the Marquesas 
Keys) (Cannon et al. 2007, pp. 1-24; 2010, pp. 847-848). The eight 
sites occupied by Miami blues ranged from approximately 0.25 to 37.10 
acres (0.1-15.0 ha) (Cannon et al. 2007, p. 6; 2010, p. 848). The 
combined amount of upland habitat of occupied sites (within KWNWR) was 
roughly 59 acres (23.8 ha) (Cannon et al. 2010, p. 848). Miami blues 
were not found on Woman Key, approximately 10.1 miles (16.2 km) west of 
Key West, or Man Key, approximately 6.8 miles (10.9 km) west of Key 
West; these sites had abundant nectar plants, but few host plants 
(Cannon et al. 2007, pp. 5, 12; 2010, pp. 848-850). In addition, the 
Miami blue was not found on six islands in the Great White Heron 
National Wildlife Refuge (GWHNWR); these sites contained limited 
amounts of, or were lacking, either host plants or nectar plants 
(Cannon et al. 2007, pp. 5, 12; 2010, pp. 847, 850-851).
    In a separate study, Daniels also found four of the sites 
previously occupied within KWNWR to support the Miami blue variously 
from 2008 to 2010 (Emmel and Daniels 2008, pp. 7-10; 2009, pp. 9-13; 
Daniels 2008, pp. 1-6; Daniels 2010, pp. 3-5; J. Daniels, pers. comm. 
2010a). Survey effort, however, was limited. Some previously occupied 
islands were not searched, and no new occupied areas were identified.
    Followup presence and absence surveys by KWNWR in 2009 showed that 
the Miami blue was present on two sites in the Marquesas, but not on 
Boca Grande (P. Cannon, pers. comm. 2010a). In 2010, similar surveys 
indicated that the Miami blue was present on Boca Grande and one site 
in the Marquesas; it was still not located on Woman Key (P. Cannon, 
pers. comm. 2010b; T. Wilmers, pers. comm. 2010a). In March and April 
2011, Miami blues were still present on five of seven sites where 
previously found in KWNWR (T. Wilmers pers. comm. 2011a; N. Haddad, 
North Carolina State University [NCSU], pers. comm. 2011).


    Although Miami blue butterflies were successfully reared in 
captivity, reintroductions have been unsuccessful. Since 2004, 
approximately 7,140 individuals have been released (J. Daniels pers. 
comm. as cited in FWC 2010, p. 8). Between August 2007 and November 
2008, reintroduction events were carried out at BNP and DJSP 12 times 
resulting in the release of 3,553 individuals (276 adults/3,277 larvae) 
(Emmel and Daniels 2009, p. 4). Monitoring efforts have been limited; 
19 days were spent monitoring reintroduction sites (Emmel and Daniels 
2009, p. 4). To date, no evidence of colony establishment has been 
found (Emmel and Daniels 2009, p. 4). It is not clear why 
reintroductions were unsuccessful. Numerous factors may have been 
involved (e.g., predation, parasitism, insufficient host plant or 
larval sources). Due to limited resources and other constraints, 
standard protocols were not employed to help identify factors that may 
have influenced reintroduction success. Research with surrogate species 
may be helpful to better establish protocols and refine techniques for 
the Miami blue prior to future propagation and reintroduction efforts.

Population Estimates and Status

Bahia Honda State Park metapopulation

    Prior to its apparent extirpation, the metapopulation at BHSP was 
monitored regularly from 2002 to 2009 (Emmel and Daniels 2009, p. 4). 
Pollard transects at the south-end colony site (largest) yielded annual 
peak counts of approximately 175, 84, 112, and 132, from 2002 to 2005 
(prior to hurricanes), and 82, 81, 120, and 38, from 2006 to 2009 
(Emmel and Daniels 2009, p. 4). From October 2002 to September 2003, 
abundance estimates using mark-release-recapture (Schnabel method) 
ranged from a low of 19.7 in February 2003 to a high of 114.5 in June 

[[Page 49548]]

(Emmel and Daniels 2004, p. 9). Counts ranged from 6 to 100 adults 
during surveys by the NABA conducted from February 2004 to January 2005 
(NABA 2005, unpub. data). Monthly (2003 to 2006) or bimonthly (2007) 
monitoring by Salvato (pers. comm. 2011c) at the south-end colony 
produced annual average counts of 129, 58, 46, 6, and 8, respectively, 
from 2003 to 2007. Salvato (pers. comm. 2011c) observed 21, 10, and 0 
Miami blues from 2008 to 2010, respectively, based on limited surveys.
    In general, early (dry) season numbers were low in most years and 
were attributed to a persistent south Florida drought (Emmel and 
Daniels 2009, p. 4). Abundance trends indicated that there was a marked 
decrease in the number of individuals during the winter months 
(November to February) (Emmel and Daniels 2004, p. 9; 2009, p. 4). 
Higher abundances during the summer wet season may relate to production 
of a large quantity of new terminal growth on the larval host plants 
(nickerbean) and availability of nectar sources from spring rainfall 
(Emmel and Daniels 2004, pp. 9-11).
    Four hurricanes affected habitat at BHSP in 2005, resulting in 
reduced abundance of Miami blue following subsequent storms that 
continued throughout 2006 (Salvato and Salvato 2007, p. 160). Although 
no quantitative measures were taken, a significant portion of the 
nickerbean in the survey area (> 35 percent of the area of available 
habitat) was damaged by the storms; roughly 60-80 percent of the 
vegetation on the southern side of the island was visually estimated to 
have been heavily damaged, including large stands of host and nectar 
plants (Salvato and Salvato 2007, p. 156). Despite a decline in 
abundance after the hurricanes, the Miami blue had appeared to rebound 
toward pre-storm abundance by the summer months of 2007 (Salvato and 
Salvato 2007, p. 160). However, peaks remained below those found prior 
to the 2005 hurricane season (Emmel and Daniels 2009, p. 4).
    Although it is unclear when iguanas became established at BHSP, 
effects of herbivory on the host plant were apparent by late 2008 or 
early 2009 (Emmel and Daniels 2009, p. 4; Daniels 2009, p. 5; P. 
Cannon, pers. comm. 2009; A. Edwards, pers. comm. 2009; P. Hughes, 
pers. comm. 2009; M. Salvato, pers. comm. 2010a). Defoliation was 
mostly limited to the south-end colony site (Emmel and Daniels 2009, p. 
4). Cooperative eradication efforts to address this problem began in 
2009 and continue today; however, iguanas continue to impact terminal 
nickerbean growth (see Summary of Factors Affecting the Species) (Emmel 
and Daniels 2009, p. 4; Daniels 2009, p. 5; E. Kiefer, BHSP, pers. 
comm. 2011a). From 2006 through 2009, adult or immature Miami blues 
were found at several colony sites; however, one colony became 
relatively unproductive in 2005 (pre-hurricane) (Emmel and Daniels 
2009, p. 4). No Miami blues have been found at any roadway nickerbean 
patches within BHSP since 2005, prior to the advent of profound iguana 
herbivory and damages from hurricanes (Emmel and Daniels 2009, p. 4).
    The metapopulation has diminished in recent years likely due to the 
combined effects of small population size, drought, cold temperatures, 
and iguanas (see Summary of Factors Affecting the Species). In 2010, 
few Miami blues were observed at BHSP. On January 23, 2010, a 
photograph was taken of a pair of Miami blues mating (Olle 2010, p. 5). 
On February 12, 2010, a photograph was taken of a single adult (C. 
DeWitt, pers. comm. 2011). In March 2010, Daniels found one larva, but 
no adults (D. Cook, FWC, pers. comm. 2010a). In July 2010, a single 
adult was observed and photographed (A. Edwards, pers. comm. 2011). No 
Miami blue adults have been located during quarterly surveys conducted 
in 2010 by Salvato (pers. comm. 2010b, 2011c). No Miami blue 
butterflies of any life stage were subsequently seen despite frequent 
searches (D. Cook, pers. comm. 2010a; P. Cannon, pers. comm. 2010c, 
2010d, 2010e, 2010f; M. Salvato, pers. comm. 2011c, 2011d; Jim 
Duquesnel, BHSP, pers. comm. 2011a, 2011b).

Key West National Wildlife Refuge Metapopulation(s)

    The metapopulation at KWNWR yielded counts of several hundred, at 
various times, in 2006-2007. Checklist counting was used during surveys 
conducted between November 2006 and July 2007 to document the 
distribution and abundance of Miami blues (Cannon et al. 2007, p. 5; 
2010, p. 848). Within the seven sites occupied in the Marquesas Keys, 
the highest counts ranged from 8 to 521 depending upon site and 
sampling date (Cannon et al. 2007, p. 7; 2010, p. 848). The highest 
count on Boca Grande was 441 in February 2007 (Cannon et al. 2007, p. 
7; 2010, p. 848). Highest counts occurred when blackbead flowered 
profusely and produced new leaves (Cannon et al. 2010, p. 851). In 
March and April, blackbead was observed to yield little new growth and 
no flowering, and oviposition by Miami blues was not observed (Cannon 
et al. 2007, p. 8). Partial searches on two islands in May and June 
revealed few Miami blues; little new leaf growth and no flowering of 
blackbead was observed at these locations after February 2007 (Cannon 
et al. 2010, p. 850). Seasonality observed on KWNWR was different than 
that described for the BHSP metapopulation (above). Hurricane Wilma 
(October 2005) heavily damaged or killed blackbead stands at most 
sites, but it also likely enhanced foraging habitat, if only 
temporarily, on select islands within the KWNWR (Cannon et al. 2007, p. 
10; 2010, p. 851) (see Summary of Factors Affecting the Species).
    Periodic surveys at KWNWR in 2008 and 2009 suggested lower levels 
of abundance, based upon limited effort (Emmel and Daniels 2008, pp. 7-
10; 2009, pp. 9-13). In February 2008, researchers recorded 3 adults on 
Boca Grande and a total of 32 adults at two islands within the 
Marquesas; lack of rainfall resulted in very limited adult nectar 
sources and limited new growth of larval host (Emmel and Daniels 2008, 
pp. 7-8). In April 2008, one adult was recorded on Boca Grande; one 
adult was also recorded at another island (Emmel and Daniels 2008, p. 
8). In June 2008, no adults were located on Boca Grande, and a total of 
27 were recorded from two other islands (Emmel and Daniels 2008, p. 9). 
In August 2008, no adults were found at Boca Grande, and five adults 
were recorded at another island (Emmel and Daniels 2008, p. 10). In 
March 2009, no adults were recorded on Boca Grande; habitat conditions 
were deemed very poor, with limited new host growth and available 
nectar resources (Emmel and Daniels 2009, p. 12). In April 2009, 
researchers found a total of 22 adults from two islands within the 
Marquesas (Emmel and Daniels 2009, p. 13).
    Based upon limited data and observations, the Miami blue persisted 
on various islands within the KWNWR in 2010. From April through July 
2010, the Miami blue was observed on 5 of 10 dates at one location 
within the Marquesas, although in limited numbers during brief surveys 
(T. Wilmers, pers. comm. 2010b). On July 28, 2010, researchers recorded 
19 adults from three islands within the Marquesas, in limited surveys; 
another 25 adults were recorded on Boca Grande in less than 1 hour of 
survey work (J. Daniels, pers. comm. 2010a). On September 30, 2010, 
dozens of Miami blues were observed on Boca Grande; this may have 
represented an actual population size in the hundreds (N. Haddad, pers. 
comm. 2010). On November 24, 2010, researchers positively identified 48 
Miami blue adults on Boca Grande in less than 3 hours of surveys, 
noting that assessment was difficult due to the

[[Page 49549]]

many hundreds or possibly thousands of cassius blues, which were also 
present (P. Cannon, pers. comm. 2010b; T. Wilmers, pers. comm. 2010a). 
In March and April 2011, researchers observed Miami blue adults at five 
sites within KWNWR in numbers similar to those reported above (N. 
Haddad, pers. comm. 2011). In July 2011, fewer adults were observed (P. 
Hughes, pers. comm. 2011).
    At this time, it is unclear what the size of the metapopulation at 
KWNWR is or its dynamics. However, available data (given above) suggest 
wide fluctuations of adults within and between years and sites. The 
frequency of dispersal between islands is also not known (Cannon et al. 
2010, p. 852). Due to the distance between the Marquesas and Boca 
Grande (i.e., about 7 miles [11 km]) and the species' limited dispersal 
capabilities, it is possible that two (or more) distinct 
metapopulations exist within KWNWR (J. Daniels, pers. comm. 2010b). In 
September 2010, the Service initiated a new study with researchers from 
NCSU to conduct a comprehensive examination of potential habitat within 
KWNWR and GWHNWR, quantify current distribution and habitat use, and 
develop a monitoring protocol to estimate detectability, abundance, and 
occupancy parameters.

Gene Flow and Genetic Diversity Within Contemporary Populations

    Saarinen (2009, pp. 15, 29-33, 40, 44) and Saarinen et al. (2009b, 
pp. 242-244) examined 12 polymorphic microsatellite loci (noncoding 
regions of chromosomes) to assess molecular diversity and gene flow of 
wild and captive-reared Miami blue butterflies; also, one 
microsatellite locus was successfully amplified from a subset of the 
museum specimens. Although results from historical specimens should be 
interpreted with caution (due both to small sample size and the single 
microsatellite locus), Saarinen (2009, pp. 15, 50-51) reported some 
loss of diversity in the contemporary populations, though less than had 
been expected. Even with small sample sizes, historical populations 
were significantly more diverse (with generally higher effective 
numbers of alleles and observed levels of heterozygosity) than BHSP; 
KWNWR population values were between historical values and BHSP values 
(Saarinen 2009, pp. 44-46).
    Both historical and contemporary populations showed evidence of a 
metapopulation structure with interacting subcolonies (E.V. Saarinen 
and J.C. Daniels, unpub. data as cited in Saarinen 2009, p. 49). 
However, the metapopulations at BHSP and KWNWR are separated by a 
distance of more than 43 miles (70 km). Given the Miami blue's poor 
dispersal capabilities (E.V. Saarinen and J.C. Daniels, unpub. data as 
cited in Saarinen 2009, p. 22), it is highly unlikely that they 
interacted. Saarinen's work showed no gene flow and a clear distinction 
between the BHSP and KWNWR metapopulations (Saarinen 2009, pp. 36, 74, 
89) (see Summary of Factors Affecting the Species).
    Studies addressing molecular diversity at BHSP showed the effective 
number of alleles remained relatively constant over time, at both a 
monthly (generational) and annual scale (Saarinen 2009, pp. 71, 84). 
Allelic (gene) richness was also stable over time in BHSP, with values 
ranging from 2.988 to 3.121 when averaged across the 12 microsatellite 
loci from September 2005 to October 2006. These values were lower than 
those in KWNWR [3.790] (Saarinen 2009, p. 71). However, data showed 
that the BHSP metapopulation retained an adequate amount of genetic 
diversity to maintain the population in 2005 and 2006, despite 
perceived changes in overall population size (Saarinen 2009, p. 77). No 
significant evidence of a recent genetic bottleneck was found in the 
BHSP generations analyzed, however, there may have been a previous 
bottleneck that was undetectable with methods used (Saarinen 2009, pp. 
72, 85, 141).
    To explore the level of gene flow and connectivity between discrete 
habitat patches at BHSP, Saarinen (2009, pp. 64-65) conducted analyses 
at several spatial scales, analyzing BHSP as a single population (with 
no subdivision), as individual colonies occupying discrete habitat 
patches (as several groups acting in a metapopulation structure), and 
as a division of clumped colonies versus other, more spatially distant 
colonies. Analyses of microsatellite frequencies were also used to 
assess gene flow between habitat patches (Saarinen 2009, p. 72). While 
some subpopulations were well linked, others showed more division 
(Saarinen 2009, p. 73). High levels of gene flow (and relatively little 
differentiation) were apparent even between distant habitat patches on 
BHSP, and the smaller patches, such as those along the Main Road, 
appeared to be important links in maintaining connectivity (Saarinen 
2009, pp. 78, 141). Overall, gene flow between habitat patches on BHSP 
was considered crucial to maintain genetic diversity and imperative for 
the Miami blue's long-term persistence at this location (Saarinen 2009, 
p. 141).
    The metapopulation structure on KWNWR is more extensive than that 
which occurred at BHSP (Saarinen 2009, p. 49). Due to small sample 
sizes from Boca Grande, only samples from the Marquesas Keys were used 
for genetic analysis of KWNWR, and results were limited (Saarinen 2009, 
pp. 66, 72). Overall, this metapopulation was found to have higher 
genetic diversity (mean observed heterozygosity of 51 percent versus 
39.5 percent) than the BHSP population (Saarinen 2009, p. 49). Allelic 
richness (3.790 in February 2008) was also higher in KWNWR (Saarinen 
2009, pp. 71, 75). Accordingly, KWNWR is a particularly important 
source of variation to be considered for future conservation efforts 
for this taxon (Saarinen 2009, pp. 71, 75), especially if this is the 
only extant metapopulation(s) remaining. The KWNWR metapopulation 
showed signs of a bottleneck and may support the hypothesis that it is 
a newly founded population (Saarinen 2009, pp. 76, 141). Further work 
is needed to better understand the metapopulation dynamics and genetic 
implications in this population.

Previous Federal Action

    On May 22, 1984, we published a Review of Invertebrate Wildlife for 
Listing as Endangered or Threatened Species (49 FR 21664), which 
included the Miami blue butterfly (Hemiargus thomasi bethune-bakeri) as 
a category 2 candidate species for possible future listing as 
threatened or endangered. Category 2 candidates were those taxa for 
which information contained in our files indicated that listing may be 
appropriate, but for which additional data were needed to support a 
listing proposal. In a January 6, 1989, Animal Notice of Review (54 FR 
572), the Miami blue butterfly continued as a category 2 candidate, 
with a name change from bethune-bakeri to bethunebakeri. On November 
21, 1991, the Miami blue was downgraded from a category 2 to category 
3C species in an Animal Candidate Review for Listing as Endangered or 
Threatened Species (56 FR 58830), characterized as having an unknown 
trend (meaning additional survey work was required to determine the 
current trend). Category 3C species were those taxa that had proved to 
be more abundant or widespread than previously believed and/or those 
that were not subject to any identifiable threat. In 1996, Category 3 
species were removed from the candidate list (61 FR 7596).
    On June 15, 2000, we received a petition from the NABA and Mark 
Salvato to emergency list the Miami

[[Page 49550]]

blue butterfly (Hemiargus thomasi bethunebakeri) as endangered with 
critical habitat pursuant to the Act. The petition cited habitat loss 
and fragmentation, influence of mosquito control chemicals, unethical 
butterfly collection, and human-caused changes to habitat occupied by 
the subspecies' only known population.
    On August 29, 2001, the Department of the Interior reached an 
agreement with several conservation organizations regarding a number of 
listing actions that had been delayed by court-ordered critical habitat 
designations and listing actions for other species. That agreement was 
subsequently approved by the U.S. District Court for the District of 
Columbia. Under the agreement, we and the conservation organizations 
agreed to significantly extend the actions on the other species, 
thereby making funds available for a number of listing actions judged 
to be higher priority. Those higher priority listing actions included 
the 90-day finding for the petition to list the Miami blue butterfly.
    On January 3, 2002 (67 FR 280), we announced our 90-day finding for 
the petition to list the Miami blue, initiated a status review, and 
sought data and information from the public. In this finding, we 
indicated the Miami blue may be in danger of extirpation. However, we 
did not believe the threats to be so great that extirpation was 
imminent, requiring us to provide emergency protection to the butterfly 
through our emergency listing provisions. We indicated that we could 
issue an emergency rule when an immediate threat posed a significant 
risk to the well-being of the subspecies.
    On May 11, 2005, we recognized the Miami blue butterfly as a 
Federal candidate subspecies in our annual Candidate Notice of Review 
(70 FR 24872). This action constituted a 12-month finding for the 
subspecies in which it was determined that the subspecies was warranted 
but precluded for listing by other higher priority listing actions. On 
November 9, 2009, in our annual Candidate Notice of Review (74 FR 
57809), we changed the Listing Priority Number (LPN) for the Miami blue 
from 6 to 3 due to increased and more immediate threats.
    On August 10, 2010, the Service received a renewed petition from 
the NABA for emergency listing of the Miami blue butterfly as 
endangered. This petition stated that the entire remaining population 
is in significant and immediate danger because it exists in a single 
location and is subject to hurricanes, iguanas, and human impacts given 
that the area is remote and difficult to patrol. On January 11, 2011, 
the Service received a separate petition for emergency listing of the 
Miami blue butterfly with critical habitat from the Center for 
Biological Diversity.
    The Miami blue butterfly is currently a Federal candidate (LPN of 
3) and State-threatened subspecies.
    The Service's decision to emergency list the Miami blue butterfly 
resulted from our careful review of the status of the subspecies and 
the threats it faces. We based this decision on information in our 
files or otherwise available to us (including the results of recent 
status surveys) as well as information contained in the original 
petition (2000), the renewed petition (2010), the new petition (2011), 
and information referenced in the petitions.
    The proposed rule to list the Miami blue butterfly as endangered is 
published concurrently with this emergency rule and found in this issue 
of the Federal Register in Proposed Rules.

Summary of Factors Affecting the Species

    Section 4 of the Act (16 U.S.C. 1533), and its implementing 
regulations at 50 CFR part 424, set forth the procedures for adding 
species to the Federal Lists of Endangered and Threatened Wildlife and 
Plants. Under section 4(a)(1) of the Act, we may determine a species to 
be endangered or threatened due to one or more of the following five 
factors: (A) The present or threatened destruction, modification, or 
curtailment of its habitat or range; (B) overutilization for 
commercial, recreational, scientific, or educational purposes; (C) 
disease or predation; (D) the inadequacy of existing regulatory 
mechanisms; or (E) other natural or manmade factors affecting its 
continued existence. Listing actions may be warranted based on any of 
the above threat factors, singly or in combination. Each of these 
factors is discussed below.
A. The Present or Threatened Destruction, Modification, or Curtailment 
of Its Habitat or Range
    The Miami blue has experienced substantial destruction, 
modification, and curtailment of its habitat and range (see Background, 
above), with an estimated > 99 percent decline in area occupied (FWC 
2010, p. 11). Although many factors likely contributed to its decline, 
some of which may have operated synergistically, habitat loss, 
degradation, and fragmentation are undoubtedly major forces that 
contribute to its imperilment (Calhoun et al. 2002, pp. 13-19; Saarinen 
2009, p. 36).

Human Population Growth and Development

    The geographic range of this butterfly once extended from the Dry 
Tortugas north along the Florida coasts to about St. Petersburg and 
Daytona. It was most common on the southern mainland and the Keys, and 
more localized on the Gulf coast. Examination of museum collections 
indicated that specimens were common from the early 1900s to the 1980s; 
the butterfly was widely distributed, existing in a variety of 
locations in southern Florida for decades (Saarinen 2009, p. 46). 
However, through time, much of this subspecies' native habitat has been 
lost, degraded, or fragmented, especially on the mainland, largely from 
development and urban growth (Lenczewski 1980, p. 47; Minno and Emmel 
1994, pp. 647-648; Calhoun et al. 2002, p. 18; Carroll and Loye 2006, 
p. 25).
    On the east coast of Florida, the entire coastline in Palm Beach, 
Broward, and Miami-Dade Counties (as far south as Miami Beach) is 
densely urban, with only small remnants of native coastal vegetation 
conserved in fragmented natural areas. Most of the Gulf Coast barrier 
islands that previously supported the Miami blue, including Marco and 
Chokoloskee Islands, have experienced intense development pressure and 
undergone subsequent habitat loss (Calhoun et al. 2002, p. 18). In an 
independent survey of historical sites where the Miami blue had 
previously been observed or collected, half were found to be developed 
or no longer supporting host plants in 2002 (D. Fine, unpub. data, 
pers. comm. 2002).
    Significant land use changes have occurred through time in south 
Florida. Considering political and economic structure and changes, 
Solecki (2001, pp. 339-356) divided Florida's land-use history into 
three broad eras: Frontier era (1870-1930), development era (1931-
1970), and globalization era (1971-present). Within the development 
era, Solecki (2001, p. 350) noted that: ``Tremendous change took place 
from the early 1950s to the early and mid-1970s. Between 1953 and 1973, 
nearly 5,800 km\2\ (28, 997 ha/year) of natural areas were lost to 
agricultural and urban land uses (Solecki and Walker, 2001).'' During 
this time, ``an almost continuous strip of urban development became 
present along the Atlantic coast'' and ``urban land uses became well 
established in the extreme southeastern part of the region particularly 
around the cities of Miami and Fort Lauderdale, and along the entire 
coastline heading northward to West Palm Beach.''

[[Page 49551]]

    Saarinen (2009, pp. 42, 46) examined museum collections in the 
context of Solecki's development eras and found that Miami blue records 
for Miami-Dade County were highest in the 1930s and 1940s, prior to 
massive land use changes and urbanization. Records from Monroe County 
(including the Keys) were most numerous in the 1970s (Saarinen 2009, p. 
46). Calhoun (pers. comm. 2003b) suggested the butterfly reached peak 
abundance when balloonvine invaded clearings associated with the 
construction boom of the 1970s and 1980s in the northern Keys and 
southern mainland and became available as a suitable host plant. If so, 
this may have represented a change in primary host plant at a time when 
the subspecies was beginning to decline due to continued development 
and destruction of coastal habitat. Saarinen (2009, p. 46) could not 
correlate decreases in natural land areas with changes in the numbers 
collected (or abundance), due to several confounding factors (e.g., 
increased pesticide use, exotic species). Calhoun et al. (2002, p. 13) 
also attributed the butterfly's decline to loss of habitat due to 
coastal development, but acknowledged that other factors such as 
succession, tropical storms, and mosquito control also likely 
exacerbated the decline (see Factor E).
    Habitat loss and human population growth in coastal areas on the 
mainland and the Keys is continuing. Human population in south Florida 
has increased from less than 20,000 people in 1920 to more than 4.6 
million by 1990 (Solecki 2001, p. 345). Monroe County and Miami-Dade 
County, two areas where the butterfly was historically abundant, have 
increased from less than 30,000 and 500,000 people in 1950, 
respectively, to more than 73,000 and 2.5 million in 2009 (http://quickfacts.census.gov). All available vacant land in the Keys is 
projected to be consumed by human population increases (i.e., 
developed) by 2060, including lands not accessible by automobile (Zwick 
and Carr 2006, p. 14). Scenarios developed by Massachusetts Institute 
of Technology (MIT) urban studies and planning department staff 
(Flaxman and Vargas-Moreno 2010, pp. 3-4) include both trend and 
doubling population estimates combined with climate change factors (see 
below) and show significant impacts on remaining conservation lands, 
including the refuges, within the Keys. While the rate of development 
in portions of south Florida has slowed in recent years, habitat loss 
and degradation, especially in desirable coastal areas, continues and 
is expected to increase.
    Although extensive loss and fragmentation of habitat has occurred, 
significant areas of suitable larval host plants still remain on 
private and public lands. Results from surveys (2002-2003) within south 
Florida and the Keys showed that numerous areas still contained host 
plants (Emmel and Daniels 2004, pp. 3-6). Results from similar surveys 
in 2007-2009 suggested that 14 of 16 sites on the mainland and 20 of 22 
in the Keys contained suitable habitat (Emmel and Daniels 2009, pp. 6-
8). Other researchers noted that larval host plants are common in the 
Keys (Carroll and Loye 2006, p. 24; Minno and Minno 2009, p. 9). A 
search of The Institute for Regional Conservation's (IRC) database 
suggests that 79 conservation areas in south Florida contain 
Caesalpinia spp., 39 areas contain Cardiospermum spp., and 77 contain 
Pithecellobium spp. (http://www.regionalconservation.org/ircs/database/search). With significant areas of host plants still remaining in 
portions of the butterfly's range, there is potential for additional 
populations of the Miami blue to exist.
    Acute habitat fragmentation has apparently severely diminished the 
butterfly's ability to repopulate formerly inhabited sites or to 
successfully locate host plants in new areas (Calhoun et al. 2002, p. 
18). Although larval host plants remain locally common, the 
disappearance of core populations and extent of habitat fragmentation 
may now prevent the subspecies from colonizing new areas (J. Calhoun, 
pers. comm. 2003b). The Miami blue is sedentary and not known to travel 
far from pockets of larval host plants and adult nectar sources (J. 
Calhoun, pers. comm. 2003b; Emmel and Daniels 2004, p. 6, 13). The 
presence of adult nectar sources proximal to larval host plants is 
critical to the Miami blue and may help explain its absence from areas 
that contain high larval host plant abundance but few nectar sources 
(J. Calhoun, pers. comm. 2003b; Emmel and Daniels 2004, p. 13).

Land Management Practices

    Land management practices that remove larval host plants and nectar 
sources can be a threat to the Miami blue. Some actions on public 
conservation lands may have negatively affected occupied habitat, but 
the extent of this impact is not known. For example, the Miami blue had 
been sighted in DJSP in 1996, but following removal of balloonvine as 
part of routine land management, no adults were observed (L. Cooper, 
pers. comm. 2002; J. Calhoun, pers. comm. 2003b; M. Salvato, pers. 
comm. 2003). In 2001, following the return of balloonvine, a single 
adult was observed (J. Calhoun, pers. comm. 2003b). Calhoun noted that 
the silver-banded hairstreak (Chlorostrymon simaethis), which also 
feeds on balloonvine, had also returned to the site. The silver-banded 
hairstreak has rebounded substantially on northern Key Largo within 
disturbed areas of DJSP; if any extant Miami blues remain on the 
island, reestablishment in this area is possible.
    Removal of nickerbean as part of trail maintenance and impacts to a 
tree resulting from placement of a facility may have impacted the south 
colony at BHSP in 2002 (J. Daniels, pers. comm. 2002a; P. Halupa, pers. 
obs. 2002). The tree was an apparent assembly area for display by 
butterflies during courtship (J. Daniels, pers. comm. 2002a). Damage to 
host plant and nectar sources from trimming and mowing during the dry 
season and herbivory by iguanas (see Factor E) impacted habitat 
conditions at BHSP in 2010 (D. Olle, NABA, pers. comm. 2010). More 
recently, the Florida Department of Environmental Protection (FDEP) has 
worked to improve habitat conditions at BHSP through plantings, 
modification of its mowing practices, removal of iguanas, protection of 
sensitive areas, and other actions (R. Zambrano, FWC, pers. comm. 2010; 
D. Cook, pers. comm. 2010a, 2010b; Janice Duquesnel, Florida Park 
Service [FPS], pers. comm. 2010a, 2010b; Jim Duquesnel, pers. comm. 
2010, 2011b; E. Kiefer, pers. comm. 2011a).
    Maintenance, including pruning of host vegetation along trails and 
roadsides, use of herbicides, and impacts from other projects could 
lead to direct mortality in occupied habitats (Emmel and Daniels 2004, 
p. 14). Habitat previously supporting immature stages of the butterfly 
on West Summerland Key is subject to periodic mowing for road 
maintenance by Florida Department of Transportation (FDOT) (J. Daniels, 
pers. comm. 2003c); the butterfly no longer occurs at this location 
(Emmel and Daniels 2004, p. 3; 2009, p. 8). Since Miami blues are 
sedentary with limited dispersal capabilities, alteration of even small 
habitat patches may be deleterious.
    Removal of host plants from conservation lands does not appear to 
be occurring on any large scales at this time. IRC has conducted 
extensive plant inventories on conservation lands within south Florida 
and is not aware of any attempts to eradicate balloonvine and notes 
that gray nickerbean has only rarely been controlled (i.e., 
purposefully removed or pruned, followed with

[[Page 49552]]

herbicide treatment) (K. Bradley, pers. comm. 2002). Nickerbean is 
reported to occur in all of the State parks in the Keys. It is not 
removed, but where it is a safety hazard for visitors such as when 
overgrowing into trails, it is trimmed (Janice Duquesnel, pers. comm. 
2003). Removal of host plants in or near occupied habitat remains a 
concern, given the subspecies' small population size, isolated 
occurrences, and limited dispersal capabilities (see Factor E).
    Lack of prescribed fire on public lands may have adversely affected 
the Miami blue through time, but impacts are unclear. In addition to 
being found within coastal areas and hardwood hammocks, the Miami blue 
was also known to occur within tropical pinelands, a fire-dependent 
habitat (Minno and Emmel 1993, p. 134; Calhoun et al. 2002, p. 18). 
Calhoun et al. (2002, p. 18) reported that, until the early 1990s, the 
Miami blue most commonly occurred within pine rocklands on Big Pine 
Key. In the absence of fire, pine rockland often progresses to hardwood 
hammock. Lack of fire may have resulted in habitat loss, however, the 
extent that this condition occurred is unclear and difficult to assess. 
Since the Miami blue is sedentary, changes in vegetation due to this 
and other land management practices may have exacerbated the effects of 
    In summary, a variety of land management practices on public lands 
(e.g., removal of host plants, mowing of nectar sources, and lack of 
prescribed fires) may have adversely affected the Miami blue and its 
habitat historically and continues to do so currently.

Climate Change and Sea Level Rise

    Climatic changes, including sea level rise, are major threats to 
south Florida, including the Miami blue and its habitat. Known 
occurrences and suitable habitat are in low-lying areas and will be 
affected by rising sea level. In general, the Intergovernmental Panel 
on Climate Change (IPCC) reported that the warming of the world's 
climate system is unequivocal based on documented increases in global 
average air and ocean temperatures, unprecedented melting of snow and 
ice, and rising average sea level (IPCC 2007, p. 2; 2008, p. 15). Sea 
level rise is the largest climate-driven challenge to low-lying coastal 
areas and refuges in the subtropical ecoregion of southern Florida 
(U.S. Climate Change Science Program [CCSP] 2008, pp. 5-31, 5-32). The 
long-term record at Key West shows that sea level rose on average 0.088 
inches (0.224 cm) annually between 1913 and 2006 (National 
Oceanographic and Atmospheric Administration [NOAA] 2008, p. 1). This 
equates to approximately 8.76 inches (22.3 cm) in 100 years (NOAA 2008, 
p. 1).
    In a technical paper following its 2007 report, the IPCC (2008, p. 
28) emphasized it is very likely that the average rate of sea level 
rise during the 21st century will exceed that from 1961 to 2003, 
although it was projected to have substantial geographical variability. 
Partial loss of the Greenland and Antarctic ice sheets could result in 
many feet (several meters) of sea level rise, major changes in 
coastlines, and inundation of low-lying areas (IPCC 2008, pp. 28-29). 
Low-lying islands and river deltas will incur the largest impacts (IPCC 
2008, pp. 28-29). According to CCSP (2008, p. 5-31), much of low-lying, 
coastal south Florida ``will be underwater or inundated with salt water 
in the coming century.'' This means that most occupied, suitable, and 
potential habitat for Miami blue will likely be either submerged or 
affected by increased flooding.
    The 2007 IPCC report found a 90 percent probability of an 
additional 7 to 23 inches and possibly as high as many feet (several 
meters) of sea level rise by 2100 in the Keys. This would cause major 
changes to coastlines and inundation of low-lying areas like the Keys 
(IPCC 2008, pp. 28-29). The IPCC (2008, pp. 3, 103) concluded that 
climate change is likely to increase the occurrence of saltwater 
intrusion as sea level rises. Since the 1930s, increased salinity of 
coastal waters contributed to the decline of cabbage palm forests in 
southwest Florida (Williams et al. 1999, pp. 2056-2059), expansion of 
mangroves into adjacent marshes in the Everglades (Ross et al. 2000, 
pp. 9, 12-13), and loss of pine rockland in the Keys (Ross et al. 1994, 
pp. 144, 151-155).
    Hydrology has a strong influence on plant distribution in these and 
other coastal areas (IPCC 2008, p. 57). Such communities typically 
grade from salt to brackish to freshwater species. In the Keys, 
elevation differences between such communities are very slight (Ross et 
al. 1994, p. 146), and horizontal distances are also small. Human 
developments will also likely be significant factors influencing 
whether natural communities can move and persist (IPCC 2008, p. 57; 
CCSP 2008, p. 7-6). For the Miami blue, this means that much of the 
butterfly's habitat in the Keys, as well as habitat in other parts of 
its historical range, will likely change as vegetation changes. Any 
deleterious changes to important host plants and nectar sources could 
further diminish the likelihood of the subspecies' survival and 
    The Nature Conservancy (TNC) (2010, p. 1) used Light Detection and 
Ranging (LIDAR) remote sensing technology to derive digital elevation 
models and predict future shorelines and distribution of habitat types 
for Big Pine Key based on sea level rise predictions ranging from the 
best case to worst case scenarios described by current scientific 
literature. In the Keys, models predicted that sea level rise will 
first result in the conversion of habitat and eventually the complete 
inundation of habitat. In the best case scenario, a rise of 7 inches 
(18 cm) would result in the inundation of 1,840 acres (745 ha) (34 
percent) of Big Pine Key and the loss of 11 percent of the island's 
upland habitat (TNC 2010, p. 1). In the worst case scenario, a rise of 
4.6 feet (140 cm) would result in the inundation of about 5,950 acres 
(2,409 ha) (96 percent) and the loss of all upland habitat (TNC 2010, 
p. 1). Although the Miami blue no longer occurs on Big Pine Key, it was 
historically found on this island. If modeling is accurate, under the 
worst case scenario, even upland habitat on Big Pine Key will become 
submerged, thereby making the butterfly's potential recolonization or 
survival at this and other low-lying locations in the Keys very 
    Similarly, using a spatially explicit model for the Keys, Ross et 
al. (2009, p. 473) found that mangrove habitats will expand steadily at 
the expense of upland and traditional habitats as sea level rises. Most 
of the upland and transitional habitat in the central portion of 
Sugarloaf Key is projected to be lost with a 0.2-meter rise (0.7-foot 
rise) in sea level; a 0.5-meter rise (1.6-foot rise) in sea level can 
result in a 95 percent loss of upland habitat by 2100 (Ross et al. 
2009, p. 473). Furthermore, Ross et al. (2009, pp. 471-478) suggested 
that interactions between sea level rise and pulse disturbances (e.g., 
storm surges or fire [see Factor E]) can cause vegetation to change 
sooner than projected based on sea level alone.
    Scientific evidence that has emerged since the publication of the 
IPCC Report (2007) indicates an acceleration in global climate change. 
Important aspects of climate change seem to have been underestimated 
previously, and the resulting impacts are being felt sooner. For 
example, early signs of change suggest that the 1[deg]C of global 
warming the world has experienced to date may have already triggered 
the first tipping point of the Earth's climate system--the 
disappearance of summer Arctic sea ice. This process could lead to 
rapid and abrupt climate change, rather than the

[[Page 49553]]

gradual changes that were forecasted. Other processes to be affected by 
projected warming include temperatures, rainfall (amount, seasonal 
timing, and distribution), and storms (frequency and intensity) (see 
Factor E). The MIT scenarios combine various levels of sea level rise, 
temperature change, and precipitation differences with population, 
policy assumptions, and conservation funding changes. All of the 
scenarios, from small climate change shifts to major changes, will have 
significant effects on the Keys.
    We have identified a number of threats to the habitat of the Miami 
blue which have operated in the past, are impacting the subspecies now, 
and will continue to impact the subspecies in the foreseeable future. 
Based on our analysis of the best available information, we find that 
the present and threatened destruction, modification, or curtailment of 
the subspecies' habitat is a threat to the subspecies throughout all of 
its range. We have no reason to believe that this threat will change in 
the foreseeable future. The decline of butterflies in south Florida is 
primarily the result of the long-lasting effects of habitat loss, 
degradation, and modification from human population growth and 
associated development and agriculture. Environmental effects resulting 
from climatic change, including sea level rise, are expected to become 
severe in the future and result in additional losses. Although efforts 
have been made to restore habitat in some areas, the long-term effects 
of large-scale and wide-ranging habitat modification, destruction, and 
curtailment will last into the foreseeable future.
B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes


    Rare butterflies and moths are highly prized by collectors, and an 
international trade exists in specimens for both live and decorative 
markets, as well as the specialist trade that supplies hobbyists, 
collectors, and researchers (Collins and Morris 1985, pp. 155-179; 
Morris et al. 1991, pp. 332-334; Williams 1996, pp. 30-37). The 
specialist trade differs from both the live and decorative market in 
that it concentrates on rare and threatened species (U.S. Department of 
Justice [USDJ] 1993, pp. 1-3; United States v. Skalski et al., Case No. 
CR9320137, U.S. District Court for the Northern District of California 
[USDC] 1993, pp. 1-86). In general, the rarer the species, the more 
valuable it is; prices can exceed $25,000 for exceedingly rare 
specimens. For example, during a 4-year investigation, special agents 
of the Service's Office of Law Enforcement executed warrants and seized 
over 30,000 endangered and protected butterflies and beetles, with a 
total wholesale commercial market value of about $90,000 in the United 
States (USDJ 1995, pp. 1-4). In another case, special agents found at 
least 13 species protected under the Act, and another 130 species 
illegally taken from lands administered by the Department of the 
Interior and other State lands (USDC 1993, pp. 1-86; Service 1995, pp. 
1-2). Law enforcement agents routinely see butterfly species protected 
under the Convention on International Trade in Endangered Species of 
Wild Fauna and Flora (CITES) during port inspections in Florida, often 
without import declarations or the required CITES permits (E. 
McKissick, Service Law Enforcement, pers. comm. 2011).
    Several listings of butterflies as endangered or threatened species 
under the Act have been based, at least partially, on intense 
collection pressure. Notably, the Saint Francis' satyr (Neonympha 
mitchellii francisci) was emergency-listed as endangered on April 15, 
1994 (59 FR 18324). The Saint Francis' satyr was demonstrated to have 
been significantly impacted by collectors in just a 3-year period (59 
FR 18324). The Callippe and Behren's silverspot butterflies (Speyeria 
callippe callippe and Speyeria zerene behrensii) were listed as 
endangered on December 5, 1997 (62 FR 64306), partially due to 
overcollection. The Blackburn's sphinx moth (Manduca blackburni) was 
listed as endangered on February 1, 2000 (65 FR 4770), partially due to 
overcollection by private and commercial collectors. The Schaus 
swallowtail (Heraclides [Papilio] aristodemus ponceanus), the only 
federally listed butterfly in Florida, was reclassified from threatened 
to endangered in 1984 due to its continued decline (49 FR 3450). At the 
time of its original listing, some believed that collection represented 
a threat. As the Schaus decreased in distribution and abundance, 
collection was believed to be a greater threat than at the time of 
listing (49 FR 3450).
    Collection was cited as a threat to the Miami blue in both the 
original and subsequent petitions for emergency listing. The State's 
management plan for the Miami blue acknowledges that butterfly 
collecting may stress small, localized populations and lead to the loss 
of individuals and genetic variability, but also indicates that there 
is no evidence or information on current or past collection pressure on 
the Miami blue (FWC 2010, p. 13). Butterflies in small populations are 
vulnerable to harm from collection (Gall 1984, p. 133). A population 
may be reduced to below sustainable numbers (Allee effect) by removal 
of females, reducing the probability that new colonies will be founded. 
Collectors can pose threats to butterflies because they may be unable 
to recognize when they are depleting colonies below the thresholds of 
survival or recovery (Collins and Morris 1985, pp. 162-165). There is 
ample evidence of collectors impacting other imperiled and endangered 
butterflies (Gochfeld and Burger 1997, pp. 208-209), host plants (Cech 
and Tudor 2005, p. 55), and even contributing to extirpations (Duffey 
1968, p. 94). For example, the federally endangered Mitchell's satyr 
(Neonympha mitchellii mitchellii) is believed to have been extirpated 
from New Jersey due to overcollecting (57 FR 21567; Gochfeld and Burger 
1997, p. 209).
    Although we do not have evidence of illegal collection of the Miami 
blue, we do have evidence of illegal collection of other butterflies 
from Federal lands in south Florida, including the endangered Schaus 
swallowtail. In a 1993 case, three defendants were indicted for 
conspiracy to violate the wildlife laws of the United States, including 
the Endangered Species Act, the Lacey Act, and 18 U.S.C. 371 (USDC 
1993, p. 1). Violations involved numerous listed, imperiled, and common 
species from many locales; defendants later pled guilty to the felonies 
(Service 1995, p. 1). As part of the evidence cited in the case, 
defendants exchanged butterflies taken from County and Federal lands in 
Florida and acknowledged that it was best to trade ``under the table'' 
to avoid permits and ``extra red tape'' because some were on the 
endangered species list (USDC 1993, p. 9). Acknowledging the 
difficulties in obtaining Schaus swallowtail, defendants indicated that 
they would traffic amongst each other to exchange a Schaus for other 
extremely rare butterflies (USDC 1993, p. 10). These defendants engaged 
in interstate commerce, exchanging a male Schaus in 1984 in the course 
of a commercial activity (USDC 1993, p. 11). One defendant also 
trafficked with a collector in Florida, dealing the federally listed 
San Bruno elfin butterfly (Callophrys mossii bayensis) (USDC 1993, p. 
    Illegal collection of butterflies on State, Federal, and other 
lands in Florida appears ongoing, prevalent, and damaging. As part of 
the aforementioned case, one defendant, who admitted getting caught 
collecting within ENP and Loxahatchee National Wildlife Refuge, stated 
that he ``got

[[Page 49554]]

away with it each time, simply claiming ignorance of the laws * * *.'' 
(USDC 1993, p. 13). Another defendant detailed his poaching in Florida 
and acquisition of federally endangered butterflies, acknowledging that 
he had ``fared very well, going specifically after rare stuff'' (USDC 
1993, pp. 28-29). The same defendant offered to traffic atala 
hairstreaks (Eumaeus atala), noting that he did not do very well and 
had only taken about 600 bugs in 9 days and that this number seemed 
poor for Florida (USDC, p. 46). He further stated that collecting had 
become difficult in Florida due to restrictions and extreme loss of 
habitat, admitting that he needed to poach rare butterflies from 
protected parks (USDC 1993, p. 45). Methods to poach wildlife and means 
to evade wildlife regulations, laws, and law enforcement were given 
(USDC 1993, p. 33). In a separate incident in 2008, an individual was 
observed attempting to take butterflies from Service lands in the Keys 
(D. Pharo, Service Law Enforcement, pers. comm. 2008). When confronted 
by a FWC officer, he lied about his activities; a live swallowtail 
butterfly (unidentified) was found in an envelope on his person, a 
collapsible butterfly net was found in a nearby area, and a cooler 
containing other live butterfly species was in his car (D. Pharo, pers. 
comm. 2008).
    Additionally, we are aware of and have documented evidence of 
interest in the collection of other imperiled butterflies in south 
Florida. In the aforementioned indictment, one defendant noted that 
there was a ``huge demand for Florida stuff,'' that he knew ``exactly 
where all the rare stuff is found,'' that he ``can readily get 
material,'' and that in most cases he would ``have to poach the 
material from protected parks'' (USDC 1993, p. 44). Salvato (pers. 
comm. 2011e) has also been contacted by several individuals requesting 
specimens of two Federal candidates, the Florida leafwing (Anaea 
troglodyta floridalis) and Bartram's hairstreak (Strymon acis 
bartrami), or seeking information regarding locations where they may be 
collected in the field. In addition, interest in the collection of the 
Florida leafwing was posted by two parties on at least one Web site in 
2010 along with advice on where and how to bait trap, despite the fact 
that this butterfly mainly occurs on Federal lands within ENP. Thus, 
there is established and ongoing collection pressure for rare 
butterflies, including two other highly imperiled candidate species in 
south Florida.
    We are also aware of multiple Web sites that offer specimens of 
south Florida's candidate butterflies for sale (M. Minno, pers. comm. 
2009; C. Nagano, Service, pers. comm. 2011). At one Web site, male and 
female Florida leafwing specimens can be purchased for [euro]110.00 and 
[euro]60.00 (euros), respectively (approximately $153.18 and $83.55). 
It is unclear from where the specimens originated or when these were 
collected, but this butterfly is now mainly restricted to ENP. The same 
Web site offers specimens of Bartram's hairstreak for [euro]10.00 
($13.93). Although the specifics on its collection are not clear, this 
butterfly now mainly occurs on protected Federal, State, and County 
lands. The same Web site offers specimens of two other butterflies 
similar in appearance to the Miami blue; the ceraunus blue currently 
sells for [euro]4.00 ($5.57), and the cassius blue is available for 
[euro]2.50-10.00 ($3.48-$13.93). Additionally, other subspecies of 
Cyclargus thomasi that occur in foreign countries are also for sale. It 
is clear that a market currently exists for both imperiled species and 
those similar in appearance to the Miami blue.
    The potential for unauthorized or illegal collection of the Miami 
blue (eggs, larvae, pupae, or adults) exists, despite its State-
threatened status and the protections provided on Federal (and State) 
land. Illegal collection could occur without detection at remote 
islands of KWNWR since these areas are difficult to patrol. The 
localized distribution and small population size render this butterfly 
highly vulnerable to impacts from collection. At this time, removal of 
any individuals may have devastating consequences to the survival of 
the subspecies. Although the Miami blue is no longer believed to be 
present at BHSP, its return is possible. At BHSP, the butterfly, like 
other wildlife and plant species within the Florida park system, is 
protected from unauthorized collection (Chapter 62 D-2.013(5)) (see 
Factor D). However, because BHSP is so heavily used, continual 
monitoring for illegal collections is a challenge. Daniels (pers. comm. 
2002a) believed that additional patrols would be helpful because 
unauthorized collection of specimens is possible, even though 
collection is prohibited (J. Daniels, pers. comm. 2002a). In addition, 
any colonies that might be found or become established outside of BHSP 
or other protected sites would also not be patrolled and would be at 
risk of collection.
    Although the Miami blue's status as a State-threatened species 
provides some protection, this protection does not include provisions 
for other species of blues that are similar in appearance. Therefore, 
it is quite possible that collectors authorized to collect similar 
species may inadvertently (or purposefully) collect the Miami blue 
butterfly thinking it was, or planning to claim they thought it was, 
the cassius blue, nickerbean blue, or ceraunus blue, which also occur 
in the same general geographical area and habitat type. Federal listing 
of other similar butterflies can partially reduce this threat (see 
Similarity of Appearance below) and provide added protective measures 
for the Miami blue above those afforded by the State.
    In summary, due to the few metapopulations, small population size, 
restricted range, and remoteness of occupied habitat, we believe that 
collection is a significant threat to the subspecies and could 
potentially occur at any time. Even limited collection from the small 
population in KWNWR (or other populations, if discovered) could have 
deleterious effects on reproductive and genetic viability and thus 
could contribute to its extinction.

Scientific Research and Conservation Efforts

    Some techniques (e.g., capture, handling) used to understand or 
monitor the Miami blue have the potential to cause harm to individuals 
or habitat. Visual surveys, transect counts, and netting for 
identification purposes have been performed during scientific research 
and conservation efforts with the potential to disturb or injure 
individuals or damage habitat. Mark-recapture, a common method used to 
determine population size, has been used by some researchers to monitor 
Miami blue populations. This method has received some criticism. While 
mark-recapture may be preferable to other sampling estimates (e.g., 
count-based transects) in obtaining demographic data when used in a 
proper design on appropriate species, such techniques may also result 
in deleterious impacts to captured butterflies (Mallet et al. 1987, pp. 
377-386; Murphy 1988, pp. 236-239; Haddad et al. 2008, pp. 929-940). 
Although effects may vary depending upon taxon, technique, or other 
factors, some studies suggest that marking may damage or kill 
butterflies or alter their behaviors (Mallet et al. 1987, pp. 377-386; 
Murphy 1988, pp. 236-239). Murphy (1988, p. 236) and Mattoni et al. 
(2001, p. 198) indicated that studies on various lycaenids have 
demonstrated mortality and altered behavior as a result of marking. 
Conversely, other studies have found that marking did not harm 
individual butterflies or populations (Gall 1984, pp. 139-154; Orive 
and Baughman 1989, p. 246; Haddad et al. 2008, p. 938). No studies

[[Page 49555]]

have been conducted to determine the potential effects of marking on 
the Miami blue. Although data are lacking, researchers permitted to use 
such techniques have been confident in their abilities to employ the 
techniques safely with minimal effect on individuals handled. 
Researchers currently studying the population within KWNWR have opted 
to not use mark-release-recapture techniques due to the potential for 
damage to this small, fragile butterfly (N. Haddad, pers. comm. 2011).
    Captive propagation and reintroduction activities may present risks 
if wild populations are impacted or if the species is introduced to new 
or inappropriate areas outside of its historical range (65 FR 56916-
56922). Although butterflies were successfully reared in captivity at 
the UF with the support of State and Federal agencies, efforts to 
reintroduce the Miami blue to portions of its historical range did not 
result in the establishment of any new populations (Emmel and Daniels 
2009, pp. 4-5; FWC 2010, p. 8). While some monitoring occurred 
following releases, it is not clear why captive-reared individuals did 
not persist in the wild. Perhaps experiments using surrogate species 
(e.g., other lycaenids) and more structured and intense monitoring 
following releases can help elucidate possible causes for failure and 
improve chances for reestablishment in the future.
    Declines in the captive colony in 2005 and 2006 were attributed to 
a baculovirus; consequently, this captive colony was terminated after 
30 generations and another was started with new stock from BHSP 
(Saarinen 2009, p. 92). Baculovirus infections are capable of 
devastating both laboratory and wild butterfly populations (Saarinen 
2009, pp. 99, 119). Irrevocable consequences may occur if a pathogen is 
transferred from laboratory-reared to wild populations. Genetic 
diversity within the captive colony was lost over time (between 
generations) (Saarinen 2009, p. 100). At one point, the captive colony 
was not infused with new genetic material for approximately 1 year due 
to low numbers within the wild population; decreases in genetic 
diversity, allelic richness, and number of individuals produced 
occurred during this time (Saarinen 2009, p. 100). While captive 
propagation and reintroduction efforts offer enormous conservation 
potential, there can be associated risks and ramifications to both wild 
and captive-reared individuals and populations.
    The use of captive-reared Miami blues in pesticide-use and life-
history studies can be questioned and has been criticized by some (FWC 
2010, p. 10). All experiments were conducted with captive-reared 
individuals; no wild individuals were used. Individuals used in 
experiments were not intended for release back into the wild or were 
reared specifically for this purpose. Researchers involved with the 
captive colony and others conducting scientific studies or other 
conservation efforts were authorized by appropriate agencies to conduct 
such work.
    In summary, we believe that captive propagation and reintroduction 
may be important components of the subspecies' survival and recovery, 
but such actions need to be carefully planned, implemented, and 
monitored. Any future efforts should only be initiated after it has 
been determined that: Such actions will not harm the wild population, 
rigorous standards are met, and commitments are in place to increase 
the likelihood of success and maximize knowledge gained.
    On the basis of this analysis, we find that overutilization for 
commercial, recreational, scientific, or educational purposes is a 
threat to the Miami blue. Collection is a significant threat to the 
subspecies. Based on our analysis of the best available information, we 
have no reason to believe that its vulnerability to collection and 
risks associated with scientific or conservation efforts will change in 
the foreseeable future.
C. Disease or predation
    The effects of disease or predation are not well known. Because the 
Miami blue is known from only a few locations and population size 
appears low, disease and predation could pose a threat to its survival.


    A baculovirus was confirmed within the captive colony, and 
infection caused the death of Miami blue larvae in captivity (see 
Factor B above) (Saarinen 2009, p. 120). Pathogens have affected other 
insect captive-breeding programs, however, this was the first time a 
baculovirus was found to affect a captive colony of an endangered 
Lepidopteran (Saarinen 2009, p. 120). A baculovirus or other disease or 
pathogens have the potential to destroy wild populations (Saarinen 
2009, p. 99). Plant pathogens could also negatively impact host plant 
survival, host growth, or the production of terminal host growth 
available to developing larvae (Emmel and Daniels 2004, p. 14). At this 
time, we are not aware of any disease or pathogens affecting Miami blue 
butterflies or host plants in the wild.


    Predation of adults or immature stages was not observed during 
monitoring at BHSP, despite the presence of potential predators (Emmel 
and Daniels 2004, p. 12; Trager 2009, p. 152). Several species of 
social wasps, specifically paper wasps (Polistes) and yellow jackets 
(Vespula), are known to depredate Lepidoptera on nickerbean and 
surrounding vegetation at BHSP and other sites with suitable habitat, 
but predation on Miami blue larvae was not observed (Trager 2009, p. 
152). Carroll and Loye (2006, p. 18) encountered a parasitic wasp, 
Lisseurytomella flava, during their studies of the balloonvine insects 
on northern Key Largo during the late 1980s. No wasp parasitism towards 
Miami blue larvae was noted (Carroll and Loye 2006, p. 24). However, 
this wasp, along with the Miami blue, was absent from continued 
balloonvine sampling in 2003, suggesting the wasp may have used the 
butterfly as host.
    Cannon et al. (2007, p. 16) observed wasps (unidentified) eating 
Miami blue larvae at KWNWR; wasps and dragonflies were also observed to 
chase adults in flight. Adult Miami blues were found entrapped in the 
webs of silver orb spiders (Argiope argentata) (Cannon et al. 2007, p. 
16). Trager (2009, pp. 149, 153-154) indicated that the Miami blue is 
likely depredated under natural conditions, but only predation by an 
adult brown anole lizard (Anolis sagrei) was observed during field 
studies. Iguanas likely consume eggs and pupae when opportunistically 
feeding (P. Hughes, pers. comm. 2009; Daniels 2009, p. 5; FWC 2010, p. 
13), especially since the butterfly uses the same terminal growth of 
host plants (see Factor E). Predators and parasitoids have been 
suggested as potential contributors to the butterfly's decline (M. 
Minno, pers. comm. 2010), but this has not been observed or confirmed 
in the field (Trager 2009, p. 149; Minno and Minno 2009, p. 78; FWC 
2010, pp. 13, 24).
    Overall, the extent to which native or exotic ants and other 
predators and parasitoids may pose a threat to the Miami blue is not 
clear, but deserves further attention. For example, invasive fire ants 
(Solenopsis invicta) were first confirmed in counties within the 
historical range of the Miami blue as early as 1958 (Hillsborough); 
other counties were confirmed in the late 1960s (Brevard and Volusia) 
and 1970s (Broward, Collier, Miami-Dade, Lee, Monroe) (Callcott and 
Collins 1996, p. 249); infestation has since expanded. In addition to 
the possible direct effects of predation, fire ants can also disrupt

[[Page 49556]]

arthropod communities and displace native ants. For example, in one 
study, Porter and Savignano (1990, pp. 2095-2106) found that S. invicta 
reduced species richness by 70 percent and abundance of native ants by 
90 percent.
    Both the red imported fire ant and the little fire ant (Wasmannia 
auropunctata), another invasive exotic ant, currently occur at BHSP 
(Saarinen and Daniels 2006, p. 71). In one study in Key Largo, fire 
ants were found within half of the study transects and in close 
proximity to the edge of hardwood hammock habitat (Forys et al. 2001, 
p. 257). Forys et al. (2001, p. 257) found all immature swallowtail 
life stages to be vulnerable to predation by imported fire ants and 
recognized the potential impact of this predatory insect on the 
federally endangered Schaus swallowtail and other butterflies in south 
Florida. Thus, immature life stages of the Miami blue may be vulnerable 
to predation by fire ants within its current locations or if the 
butterfly still persists, elsewhere in its historical range.
    In a greenhouse situation, Trager (2009, p. 151) observed fire ants 
removing Miami blue eggs in an indoor flight cage, but noted that the 
ants did not attack larvae on the same plant. In his studies, a captive 
colony of fire ants was found to consume captive-reared Miami blue 
pupae in food trays; however, the ants did not remove newly laid eggs 
from the host plant and even exhibited weak tending behavior toward 
larvae (Trager 2009, pp. 151-152). At this time, it is unclear to what 
extent native and exotic predatory insects may be impacting wild Miami 
blue populations.
    Some ant species may also protect Miami blue larvae against 
parasitoids and predators; however, this has not yet been observed in 
the wild (Trager and Daniels 2009, 479; Trager 2009, p. 101). In 
laboratory studies, Camponotus floridanus ants have been shown to 
display strong defensive behaviors (e.g., rapidly circling larvae, 
recruiting nearby workers, and lunging at forceps) when disturbed 
(Trager and Daniels 2009, p. 480; Trager 2009, p. 102). The large size 
of this ant species and nearly constant tending may serve as a visual 
deterrent to potential attackers; however, researchers acknowledged 
that they have no definitive evidence that C. floridanus are more 
effective defenders of Miami blue larvae than small-bodied ant species 
(Trager and Daniels 2009, p. 480; Trager 2009, p. 97).
    Researchers have suggested that some ant species may depredate 
Miami blue larvae or may opportunistically tend larvae without 
providing protection against predators or other benefits (Saarinen and 
Daniels 2006, p. 73; Saarinen 2009, pp. 134, 138). However, Trager and 
Daniels (2009, pp. 478-481) recorded a universal tending response among 
ants consistent with a mutualistic interaction through both field 
observations and laboratory trials. They did not observe any 
depredation of larvae by ants in the field and, based upon 
observations, doubted that many ant species regularly depredate larvae 
(Trager and Daniels 2009, pp. 479-481; Trager 2009, p. 149).
    Studies suggest that various stressors (e.g., baculovirus, fire 
ants) have the potential to negatively impact the Miami blue, but we do 
not have evidence of their impacts to wild populations. The Miami blue 
may have some mechanisms to potentially deter predators and 
parasitoids, but these are not well understood. Disease and predation 
have the potential to impact the Miami blue's continued survival, given 
its few remaining populations, low abundance, and limited range. Based 
on our analysis of the best available information, we do not believe 
that disease or predation is a significant threat to its overall status 
at this time. However, given its small population size, disease and 
predation have the potential to impact the subspecies now or in the 
foreseeable future.
D. The Inadequacy of Existing Regulatory Mechanisms
    Despite the fact that they contain several protections for the 
Miami blue, Federal, State, and local laws have not been sufficient to 
prevent past and ongoing impacts to the Miami blue and its habitat 
within its current and historical range.
    In response to a petition from the NABA in 2002, the FWC emergency-
listed the Miami blue butterfly in 2002, temporarily protecting the 
butterfly. On November 19, 2003, the FWC declared the Miami blue 
butterfly endangered (68A-27.003), making its protection permanent. On 
November 8, 2010, the FWC adopted a revised listing classification 
system, moving from a multi-tiered to single-category system. As a 
consequence of this change, the Miami blue butterfly (along with other 
species) became a State-threatened species; its original protective 
measures remained in place (68A-27.003, amended). This designation 
prohibits any person from taking, harming, harassing, possessing, 
selling, or transporting any Miami blue or parts thereof or eggs, 
larvae or pupae, except as authorized by permit from the executive 
director, with permits issued based upon whether issuance would further 
management plan goals and objectives. Although these provisions 
prohibit take of individuals, there is no substantive protection of 
Miami blue habitat or protection of potentially suitable habitat. 
Therefore, while the Miami blue butterfly is afforded some protection 
by its presence on Federal (and State) lands, losses of suitable and 
potential habitat outside of these areas are expected to continue (see 
Factor A).
    The Miami blue's presence on Federal (and State) lands offers some 
insulation against collection, but protection is somewhat limited (see 
Factor B). In addition, the State's protection of the Miami blue does 
not extend to butterflies that are similar in appearance (see 
Similarity of Appearance below). Since there are only slight 
morphological differences between the Miami blue and other butterfly 
species in the same areas, the Miami blue remains at-risk to illegal 
collection, despite the regulatory mechanisms already in place (see 
Factor B).
    As part of its listing process, the FWC has completed a biological 
status review and management plan for the subspecies (FWC 2003, pp. 1-
26). This management plan was recently revised (FWC 2010, pp. ii-39). 
Although the management plan is a fundamental step in outlining 
conservation needs, it may be insufficient for achieving conservation 
goals and long-term persistence. Recommended conservation strategies 
and actions within the plan are voluntary and dependent upon adequate 
funding, staffing, and the cooperation and participation of multiple 
agencies and private entities, which may or may not be available or 
able to assist. Conservation strategies include suggested actions to 
maintain, protect, and monitor known metapopulations; establish new 
metapopulations; and conduct additional research to support 
conservation (FWC 2010, pp. 17-26).
    As a Federal candidate subspecies, the Miami blue is afforded some 
protection through sections 7 and 10 of the Act and associated policies 
and guidelines, but protection is limited. Federal action agencies are 
to consider the potential effects to the butterfly and its habitat 
during the consultation process. Applicants and action agencies are 
encouraged to consider candidate species when seeking incidental take 
for other listed species and when developing habitat conservation 
plans. On Federal lands, such as KWNWR, candidate species are treated 
as ``proposed threatened.''
    Although the Miami blue occurs on Federal (and possibly State) land 
that offers protection, these areas are vast

[[Page 49557]]

and often heavily used. Signage prohibiting collection is sometimes 
lacking; patrolling and monitoring of activities can be limited and 
dependent upon the availability of staffing and resources. Within 
KWNWR, the Marquesas Keys are open to the public; portions of the beach 
on Boca Grande are closed to the public (T. Wilmers, pers. comm. 
2011b). In general, occupied islands are remote and difficult to 
patrol, and illegal use still occurs (see Factor E). Therefore, the 
potential for illegal collection and damage to sensitive habitats still 
exists (see Factors B and E).
    Prior to its apparent extirpation, the metapopulation at BHSP was 
afforded some protection by its presence on State lands. All property 
and resources owned by FDEP are generally protected from harm in 
Chapter 62D-2.013(2) and animals are specifically protected from 
unauthorized collection in Chapter 62D-2.013(5) of the Florida 
Statutes. Exceptions are made for collecting permits, which are issued, 
``for scientific or educational purposes.'' Still, protection of 
resources at BHSP is a challenge due to the park's popularity and high 
use (See Factor E). However, in 2010, the FDEP hired a temporary, full-
time biologist to work on Miami blue conservation issues at BHSP, 
including patrol of sensitive habitats.
    Permits are required from the FWC for scientific research on and 
collection of the Miami blue. For work on Federal lands (i.e., KWNWR, 
ENP, and BNP), permits are required from the Service or the NPS. For 
work on State lands, permits are required from FDEP. Permits are also 
required for work on County-owned lands.
    Despite these existing regulatory mechanisms, the Miami blue 
continues to decline due to the effects of habitat loss (see Factor A) 
and a wide array of other factors (see Factors B and E). We find that 
regulatory measures have been insufficient to significantly reduce or 
remove the threats to the Miami blue and, therefore, that the 
inadequacy of existing regulatory mechanisms is a threat to the 
subspecies throughout all of its range. Based on our analysis of the 
best available information, we have no reason to believe that the 
aforementioned regulations, which currently do not offer adequate 
protection to the Miami blue, will be improved in the foreseeable 
E. Other Natural or Manmade Factors Affecting its Continued Existence

Impacts From Iguanas

    The exotic green iguana (Iguana iguana) is a severe threat to the 
Miami blue (75 FR 69258; Daniels 2009, p. 5; FWC 2010, pp. 6, 13; Olle 
2010, pp. 4, 14). Iguanas are prevalent within the Keys, and sightings 
within occupied and potential habitat are common (P. Cannon, pers. 
comm. 2009, 2010d, 2010e). Effects of herbivory to the host plant 
(nickerbean) at BHSP were evident by late 2008 and early 2009 (Emmel 
and Daniels 2009, p. 4; Daniels 2009, p. 5; P. Hughes, pers. comm. 
2009; P. Cannon, pers. comm. 2009; A. Edwards, pers. comm. 2009). In 
January 2009, Cannon (pers. comm. 2009) reported that iguanas had 
stripped all new nickerbean growth, causing substantial losses since 
November 2008. In April 2009, nickerbean showed signs of limited growth 
due to chronic herbivory (P. Hughes, pers. comm. 2009).
    In addition to damage, iguanas likely consume eggs and pupae when 
opportunistically feeding (P. Hughes, pers. comm. 2009; Daniels 2009, 
p. 5; FWC 2010, p. 13), especially since the butterfly uses the same 
terminal growth of host plants. For many years, host plant abundance 
within BHSP appeared capable of sustaining both iguanas and Miami 
blues. Depressed numbers of Miami blues in 2008, however, were likely 
the result of both a severe drought and impacts to the nickerbean from 
iguanas feeding on the terminal nickerbean growth (FWC 2010, p. 6). 
During the winter of 2010, prolonged and unseasonably cold temperatures 
in the lower Keys resulted in a considerable decline in available 
nickerbean at BHSP (Olle 2010, p. 14). The suppressed population of the 
Miami blue at this site during this time may not have been able to 
survive this temporary, but severe, reduction in nickerbean, likely 
caused by the combined influences of iguanas and environmental factors 
(e.g., drought and cold).
    Iguana tracks were found on islands occupied by the Miami blue in 
KWNWR (Cannon et al. 2007, p. 16; T. Wilmers, pers. comm. 2011c). Three 
large, gravid female iguanas were trapped and removed from the 
Marquesas in February 2011 (T. Wilmers, pers. comm. 2011d). To date, 
the presence of iguanas has been documented on four islands (two 
islands within the Marquesas, and Boca Grande and Woman Key) (T. 
Wilmers, pers. comm. 2011a). Cannon et al. (2007, p. 16) stated that 
the exotic herbivore has the potential to impact host and nectar 
plants. Iguanas have also been observed on three islands in GWHNWR 
(Snipe Point, Sawyer Key, and Secret Key) since 2006 (T. Wilmers, pers. 
comm. 2011b).
    Resource agencies are working to combat the threat of green iguanas 
in areas occupied (and recently occupied) by the Miami blue. At BHSP, 
cooperative efforts have resulted in the trapping and removal of 130 
iguanas between November 2009 and June 2011 (Emmel and Daniels 2009, p. 
4; FWC 2010, p. 17; E. Kiefer, pers. comm. 2011a, 2011b). While removal 
efforts have significantly decreased the number of iguanas within BHSP, 
these management actions will need to be an ongoing effort due to the 
prevalence of iguanas in the surrounding areas (R. Zambrano, pers. 
comm. 2009). Efforts are also underway to address this threat at KWNWR 
(T. Wilmers, pers. comm. 2011a, 2011c, 2011d, 2011e). Despite 
cooperative efforts, the threat from iguanas is expected to continue 
due to their widespread distribution and the difficulties in control.


    Host resource competition from other butterfly species could 
deleteriously impact metapopulation productivity of the Miami blue. The 
introduction of or future island colonization by potential Lepidopteran 
competitors may impact the Miami blue metapopulation. The nickerbean 
blue, cassius blue, and Martial's scrub hairstreak are known to use 
various species of nickerbean host plants throughout their range 
(Glassberg et al. 2000, pp. 74-80; Calhoun et al. 2002, p. 15). The 
nickerbean blue and Martial's scrub hairstreak have been documented 
using gray nickerbean as a host plant at BHSP (Daniels et al. 2005, p. 
174; P. Cannon, pers. comm. 2010g). Such host use may represent direct 
competition for host resources (Emmel and Daniels 2004, p. 14). 
However, Calhoun et al. (2002, p. 18) believed it was unlikely that 
competition played a significant role in the decline of the Miami blue 
based on the abundance of host plant sources available to lycaenids 
throughout the Lower Keys. We do not have evidence to suggest that host 
resource competition is a threat to the Miami blue at this time or is 
likely to become so in the future.

Inadvertent Impacts From Humans

    Inadvertent damage from humans can affect the Miami blue and its 
habitat in its current and former range. For example, the seed pods of 
balloonvine ``pop'' when squeezed and can be targeted by humans. Damage 
to balloonvine has been documented along roads in the Keys (J. Loye, 
University of California-Davis, pers. comm. 2003a, 2003b). During a 
study in the mid 1980s examining balloonvine and its associated insect 
community, Loye (pers. comm. 2003a) found a difference in insect 
diversity between sites along

[[Page 49558]]

roads and those without road access. Acknowledging other possible 
contributing factors (e.g., mosquito control, car emissions), Loye 
(pers. comm. 2003a) indicated that collectors and maintenance crews 
damaged balloons near roads, stating that ``humans damaged every 
balloon that could be easily found at our study sites'' (J. Loye, pers. 
comm 2003b). It is not clear what, if any, impact this had on the 
butterfly at or since that time. However, damage to host plants (whole 
or parts) could contribute to mortality of eggs or larvae.
    BHSP is heavily used by the public for recreational purposes, and 
although the butterfly has not been seen at this location since early 
2010, suitable habitat is located along trails and other high-use areas 
(e.g., campgrounds). Former colonies may have experienced disturbance 
from Park visitors. Trampling of host plants and well-worn footpaths 
were evident, at least periodically from 2002 to 2010, and during times 
when other stressors (e.g., cold, drought, iguanas) occurred (P. 
Halupa, pers. obs. 2002; D. Olle, pers. comm. 2010; M. Salvato, pers. 
comm. 2010a; R. Zambrano, pers. comm. 2010). To protect larval host 
plants and adult nectar sources, the Florida Park Service (FPS) erected 
fencing and signage around the majority of the south colony site at 
BHSP. Although this is expected to minimize damage to the largest 
habitat patch, other small habitat patches (as small as 15.0 by 15.0 
feet [4.6 by 4.6 meters]) elsewhere on the island are still vulnerable 
to intentional or accidental damage. Fencing small colony sites or 
patches of available habitat is impractical and would make exact 
locations of colonies more evident, possibly increasing the risk of 
illegal collection or harm should the Miami blue return to the island.
    KWNWR lacks human developments, but local disturbances result from 
illicit camping, fire pits, smugglers, vandals, and immigrant landings. 
These disturbances are generally infrequent for most islands within 
KWNWR with the exception of Boca Grande, which contains the largest 
amounts of beach. Recreational visitation is high on Boca Grande, 
particularly during weekends (Cannon et al. 2010, p. 852). Trampling of 
dune vegetation has been a long-term problem on Boca Grande, and fire 
pits have been found many times over the past two decades on both Boca 
Grande and the Marquesas Keys (Cannon et al. 2010, p. 852). In 
addition, the large amount of dead vegetation intermingled with host 
plants on Boca Grande and the Marquesas Keys makes the threat of fire 
(natural or human-induced), a significant threat to the Miami blue 
(Cannon et al. 2007, p. 13; 2010, p. 852). Immature stages (eggs, 
larvae), which are sedentary, would be particularly vulnerable. 
Glassberg and Olle (2010, p. 1) asserted that ``the proximity of the 
islands within KWNWR, to both Key West and the Dry Tortugas, invite 
human mischief, and largely go unpoliced.'' These areas within KWNWR 
are remote and accessible mainly by boat, making them difficult to 
patrol and monitor.
    In summary, inadvertent impacts from humans may have affected the 
Miami blue and its habitat. Due to the location of occupied and 
suitable habitat, the popularity of these areas with humans, and the 
projected human growth especially in coastal areas, such impacts from 
recreation and other uses are expected to continue.

Other Natural and Unnatural Changes to Habitat

    Natural changes to vegetation from environmental factors, 
succession, or other causes may now be a threat to the Miami blue 
because of its severely reduced range, few populations, and limited 
dispersal capabilities. Suitable and occupied habitat in KWNWR and 
other coastal areas is dynamic and fluctuating, influenced by a variety 
of environmental factors (e.g., storm surge, wind, precipitation). In 
2010, substantial changes in habitat conditions on Boca Grande occurred 
with the proliferation of Galactia striata, a native climbing vine (T. 
Wilmers, pers. comm. 2010a; P. Cannon, pers. comm. 2010b, 2010h, 2010i, 
2010j). The vine has enveloped a substantial amount of blackbead, 
occurring on about 40 percent of the blackbead growing on the seaward 
side at the dune interface (T. Wilmers, pers. comm. 2010a). Wilmers 
(pers. comm. 2010a) believes that the extensive growth was likely 
fueled by the markedly higher precipitation during September and 
October 2010 (3.47 and 2.22 inches [8.81 and 5.64 cm], respectively, 
above normal in Key West). Under favorable conditions, the vine first 
grows in the dune, then sprawls landward laterally, eventually 
ascending and blanketing blackbead (T. Wilmers, pers. comm. 2010a). 
While climbing vines can proliferate before eventually dying back, 
Wilmers (pers. comm. 2010a) states that the intense proliferation in 
2010 is unprecedented in his 25 years of work in the area. It is 
unclear what steps are needed at this time. Left unchecked, this 
proliferation has the potential to impact host plants and affect the 
butterfly's ability to persist on some islands.

Invasive and Exotic Vegetation

    Displacement of native plants including host plants by invasive 
exotic species, a common problem throughout south Florida, also 
possibly contributed to habitat loss of the Miami blue. In coastal 
areas where undeveloped land remains, the Miami blue's larval food 
plants are likely to be displaced by invasive exotic plants, such as 
Brazilian pepper, Australian pine (Casuarina equesitifolia), Asian 
nakedwood (Colubrina asiatica), cat-claw vine (Macfadyena ungius-cati), 
wedelia (Spahneticola trilobata), largeleaf lantana (Lantana camara), 
Portia tree (Thespesia populnea), wild indigo (Indigofera spicata), 
beach naupaka (Scaevola taccada), and several species of invasive 
grasses. Although we do not have direct evidence of exotic species 
displacing host plants or nectar sources, we recognize this as a 
potential threat, due to the magnitude of this problem in south 


    Efforts to control salt marsh mosquitoes, Aedes taeniorhynchus, 
among others, have increased as human activity and population have 
increased in south Florida. To control mosquito populations, second-
generation organophosphate (naled) and pyrethroid (permethrin) 
adulticides are applied by mosquito control districts throughout south 
Florida. The use of pesticides (applied using both aerial and ground-
based methods) to control mosquitoes presents a potential risk to 
nontarget species, including the Miami blue butterfly.
    The potential for mosquito control chemicals to drift into 
nontarget areas and persist for varying periods of time has been well 
documented. Hennessey and Habeck (1989, pp. 1-22; 1991, pp. 1-68) and 
Hennessey et al. (1992, pp. 715-721) illustrated the presence of 
mosquito spray residues long after application in habitat of the Schaus 
swallowtail and other imperiled species in both the upper (Crocodile 
Lake NWR, North Key Largo) and lower Keys (National Key Deer Refuge 
[NKDR], Big Pine Key). Residues of aerially applied naled were found 6 
hours after application in a pineland area that was 820 yards (750 
meters) from the target area; residues of fenthion (an adulticide no 
longer used in the Keys) applied via truck were found up to 55 yards 
(50 meters) downwind in a hammock area 15 minutes after application in 
adjacent target areas (Hennessey et al. 1992, pp. 715-721).
    More recently, Pierce (2009, pp. 1-17) monitored naled and 

[[Page 49559]]

deposition following application in and around NKDR from 2007 to 2009. 
Permethrin, applied by truck, was found to drift considerable distances 
from target areas with residues that persisted for weeks. Naled, 
applied by plane, was also found to drift into nontarget areas but was 
much less persistent exhibiting a half-life of approximately 6 hours. 
In 2009, Tim Bargar (U.S. Geological Survey, pers. comm. 2011) 
conducted two field trials on NKDR that detected significant naled 
residues at locations within nontarget areas on the refuge that were up 
to 440 yards (402 m) from the edge of zones targeted for aerial 
    In addition to mosquito control chemicals entering nontarget areas, 
the toxic effects of mosquito control chemicals to nontarget organisms 
have also been documented. Lethal effects on nontarget Lepidoptera have 
been attributed to fenthion and naled in both south Florida and the 
Keys (Emmel 1991, pp. 12-13; Eliazar and Emmel 1991, pp. 18-19; Eliazar 
1992, pp. 29-30). In the lower Keys, Salvato (2001, pp. 8-14) and 
Hennessey and Habeck (1991, p. 14) suggested that declines in 
populations of the Florida leafwing (now a Federal candidate) were also 
partly attributable to mosquito control chemical applications. Salvato 
(2001, p. 14; 2002, pp. 56-57) found populations of the Florida 
leafwing (on Big Pine Key within NKDR) to increase during drier years 
when adulticide applications over the pinelands decreased, although 
Bartram's hairstreak did not follow this pattern. It is important to 
note that vulnerability to chemical exposure may vary widely between 
species, and current application regimes do not appear to affect some 
species as strongly as others (Calhoun et al. 2002, p. 18; Breidenbaugh 
and De Szalay 2010, pp. 594-595; Rand and Hoang 2010, pp. 14-17, 20; 
Hoang et al. 2011, pp. 997-1005).
    Dose-dependent decreases in brain cholinesterase activity in great 
southern white butterflies (Ascia monuste) exposed to naled have been 
measured in the laboratory (T. Bargar, pers. comm. 2011). An inhibition 
of cholinesterase, which is the primary mode of action of naled, 
prevents an important neurotransmitter, acetylcholine, from being 
metabolized, causing uncontrolled nerve impulses that may result in 
erratic behavior and, if severe enough, mortality. From these data, it 
was determined that significant mortality was associated with 
cholinesterase activity depression of at least 27 percent (T. Bargar, 
pers. comm. 2011). In a subsequent field study on NKDR, adult great 
southern white and Gulf fritillary (Agraulis vanillae) butterflies were 
placed in field enclosures at both target and nontarget areas during 
aerial naled application. The critical level of cholinesterase 
inhibition (27 percent) was exceeded in the majority of butterflies 
from the target areas, as well as in a large proportion of butterflies 
from the nontarget areas (T. Bargar, pers. comm. 2011). During the same 
field experiment, great southern white and Gulf fritillary larvae were 
also exposed in the field during aerial naled application and exhibited 
mortality at both target and nontarget sites (T. Bargar, pers. comm. 
    In a laboratory study, Rand and Hoang (2010, pp. 1-33) and Hoang et 
al. (2011, pp. 997-1005) examined the effects of exposure to naled, 
permethrin, and dichlorvos (a breakdown product of naled) on both 
adults and larvae of five Florida native butterfly species (common 
buckeye (Junonia coenia), painted lady (Vanessa cardui), zebra longwing 
(Heliconius charitonius), atala hairstreak (Eumaeus atala), and white 
peacock (Anartia jatrophae)). The results of this study indicated that, 
in general, larvae were slightly more sensitive to each chemical than 
adults, but the differences were not significant. Permethrin was 
generally the most toxic chemical to both larvae and adults, although 
the sensitivity between species varied.
    The laboratory toxicity data generated by this study were used to 
calculate hazard quotients (concentrations in the environment/
concentrations causing an adverse effect) to assess the risk that 
concentrations of naled and permethrin found in the field pose to 
butterflies. A hazard quotient that exceeds one indicates that the 
environmental concentration is greater than the concentration known to 
cause an adverse effect (mortality in this case), thus indicating 
significant risk to the organism. Environmental exposures for naled and 
permethrin were taken from Zhong et al. (2010, pp. 1961-1972) and 
Pierce (2009, pp. 1-17), respectively, and represent the highest 
concentrations of each chemical that were quantified during field 
studies in the Keys. When using the lowest median lethal concentrations 
from the laboratory study, the hazard quotients for permethrin were 
greater than one for each adult butterfly, indicating a significant 
risk of toxicity to each species. In the case of naled, significant 
risk to the zebra longwing was predicted based on its hazard quotient 
exceeding one.
    From 2006 to 2008, Zhong et al. (2010, pp. 1961-1972) investigated 
the impact of single aerial applications of naled on Miami blue larvae 
in the field. The study was conducted in North Key Largo in cooperation 
with the Florida Keys Mosquito Control District (FKMCD) and used 
experimentally placed Miami blue larvae that were reared in captivity. 
The study involved 15 test stations: 9 stations in the target zone, 3 
stations considered to be susceptible to drift (2 stations directly 
adjacent to the spray zone and 1 station 12 miles (19.3 km) southwest 
of the spray zone), and 3 field reference stations (25 miles (40.2 km) 
southwest of the spray zone). Survival of butterfly larvae in the 
target zone was 73.9 percent, which was significantly lower than both 
the drift zone (90.6 percent) and the reference zone (100 percent), 
indicating that direct exposure to naled poses significant risk to 
Miami blue larvae. In addition to observing elevated concentrations of 
naled at test stations in the target zone, 9 of 18 samples in the drift 
zone also exhibited detectable concentrations, once again exhibiting 
the potential for mosquito control chemicals to drift into nontarget 
    Based on these studies, it can be concluded that mosquito control 
activities that involve the use of both aerial and ground-based 
spraying methods have the potential to deliver pesticides in quantities 
sufficient to cause adverse effects to nontarget species in both target 
and nontarget areas. It should be noted that many of the studies 
referenced above dealt with single application scenarios and examined 
effects on only one to two butterfly life stages. Under a realistic 
scenario, the potential exists for exposure to all life stages to occur 
over multiple applications in a season. In the case of a persistent 
compound like permethrin where residues remain on vegetation for weeks, 
the potential exists for nontarget species to be exposed to multiple 
pesticides within a season (e.g., permethrin on vegetation coupled with 
aerial exposure to naled).
    Aspects of the Miami blue's natural history may increase its 
potential to be exposed to and affected by mosquito control pesticides 
and other chemicals. For example, host plants and nectar sources are 
commonly found at disturbed sites and often occur along roads in 
developed areas, where chemicals are applied. Ants associated with the 
Miami blue (see Interspecific relationships) may be affected in unknown 
ways. Host plant and nectar source availability may also be indirectly 
affected through impacts on pollinators. Carroll and Loye (2006, pp. 
19, 24) and others (Emmel 1991, p. 13; Glassberg and Salvato 2000, p. 
7; Calhoun et al. 2002, p. 18) suggested

[[Page 49560]]

that the Miami blue butterfly may be more susceptible to pesticides 
than perhaps other lycaenids (e.g., the silver-banded hairstreak) 
because Miami blue larvae leave entrance holes open in seed pods to 
allow access for attending ants. Ants and larvae of the Miami blue on 
balloonvine were found to die when roadside spraying for mosquito 
control began in late spring, but larvae of the silver-banded 
hairstreak (also on balloonvine) apparently survived subsequent 
spraying (Emmel 1991, p. 13). However, Minno (pers. comm. 2010) argues 
that larvae using balloonvine pods would be protected from the effects 
of pesticides because the pods have internal partitions and exposure 
would be limited due to the size of the entrance hole.
    No mosquito control pesticides are used within KWNWR. At BHSP, the 
only application of adulticides (permethrin) is occasional truck-based 
spraying in the ranger residence areas (E. Kiefer, pers. comm. 2011a). 
Mosquito control practices currently pose no risk to the Miami blue 
within KWNWR or in formerly occupied habitat at BHSP. However, mosquito 
control activities, including the use of larvicides and adulticides, 
are being implemented within suitable and potential habitat for the 
Miami blue elsewhere in its range (Carroll and Loye 2006, pp. 14-15). 
The findings of Zhong et al. (2010, pp. 1961-1972) and Pierce (2009, 
pp. 1-17) along with other studies suggest that aerial or truck-based 
applications of mosquito control chemicals may pose a threat to the 
Miami blue, if the butterfly exists in other, unknown locations. 
Additionally, mosquito control practices potentially may limit 
expansion of undocumented populations or colonization of new areas. If 
the Miami blue colonizes new areas or if additional populations are 
discovered or reintroduced, adjustments in mosquito control (and other) 
practices may be needed to help safeguard the subspecies.
    Efforts are already underway by multiple agencies and partners to 
seek ways to avoid and minimize impacts to the Miami blue and other 
imperiled nontarget species. For example, in an effort to reduce the 
need for aerial adulticide spraying, the FKMCD is increasing 
larviciding activities, which are believed to have less of an 
ecological impact on wilderness islands near NKDR and GWHNWR (FKMCD 
2009, pp. 3-4). This effort has led to a reduction in area receiving 
adulticide treatment on Big Pine Key, No Name Key, and Torch Key (FKMCD 
2009, p. 17). Another example is the Florida Coordinating Council on 
Mosquito Control (FCCMC), including the Imperiled Species Subcommittee, 
which was initially formed to resolve the conflict between mosquito 
control spraying and the reintroduction of Miami blues to their 
historical range (FWC 2010, p. 9).
    The FWC's management plan for the Miami blue also recommends the 
use of no-spray zones for all pesticides and use of buffers at or 
around Miami blue populations and other conservation measures (FWC 
2010, pp. ii-41). However, there are no specific binding or mandatory 
restrictions to prohibit such practices or encourage other beneficial 
measures. The FWC plan suggests that an aerial no-spray buffer zone of 
820 yards (750 m) be established around Miami blue populations where 
possible and that buffer zones for truck-based applications of 
adulticides also be established (FWC 2010, p. 17). The FCCMC also 
recommends that the appropriate width of buffer zones be determined by 
future research. The Service is supporting research to characterize 
drift from truck-based spraying methods. The data from this study will 
aid in better determining appropriate buffer distances around sensitive 
    In summary, although substantial progress has been made in reducing 
impacts, the potential effects of mosquito control applications and 
drift residues remain a threat to the Miami blue. We will continue to 
work with the mosquito control districts and other partners and 
stakeholders to reduce threats wherever possible.

Effects of Small Population Size and Isolation

    The Miami blue is vulnerable to extinction due to its severely 
reduced range, small population size, metapopulation structure, few 
remaining populations, and relative isolation. In general, isolation, 
whether caused by geographic distance, ecological factors, or 
reproductive strategy, will likely prevent the influx of new genetic 
material and can result in low diversity, which may impact viability 
and fecundity (Chesser 1983, pp. 66-77). Extinction risk can increase 
significantly with decreasing heterozygosity as was reported for the 
Glanville fritillary (Saccheri et al. 1998, pp. 491-494). Distance 
between metapopulations and colonies within those metapopulations and 
the small size of highly sporadic populations can make recolonization 
unlikely if populations are extirpated. Fragmentation of habitat and 
aspects of the butterfly's natural history (e.g., limited dispersal, 
reliance on host plants) can contribute to and exacerbate threats.
    Estimated abundance of the Miami blue is not known, but may number 
in the hundreds, and at times, possibly higher. Although highly 
dependent upon species, a population of 1,000 has been suggested as 
marginally viable for an insect (D. Schweitzer, The Nature Conservancy, 
pers. comm. 2003). Schweitzer (pers. comm. 2003) has also suggested 
that butterfly populations of less than 200 adults per generation would 
have difficulty surviving over the long term. In comparison, in a 
review of 27 recovery plans for listed insect species, Schultz and 
Hammond (2003, p. 1377) found that 25 plans broadly specified 
metapopulation features in terms of requiring that recovery include 
multiple population areas (the average number of sites required was 
8.2). The three plans that quantified minimum population sizes as part 
of their recovery criteria for butterflies ranged from 200 adults per 
site (Oregon silverspot [Speyeria zerene hippolyta]) to 100,000 adults 
(Bay checkerspot [Euphydryas editha bayensis]) (Schulz and Hammond 
2003, pp. 1374-1375).
    Schultz and Hammond (2003, pp. 1372-1385) used population viability 
analyses to develop quantitative recovery criteria for insects whose 
population sizes can be estimated and applied this framework in the 
context of the Fender's blue (Icaricia icarioides fenderi), a butterfly 
listed as endangered in 2000 due to its small population size and 
limited remaining habitat. They found the Fender's blue to be at high 
risk of extinction at most of its sites throughout its range despite 
that fact that the average population at 12 sites examined ranged from 
5 to 738 (Schulz and Hammond 2003, pp. 1377, 1379). Of the three sites 
with populations greater than a few hundred butterflies, only one of 
these had a reasonably high probability of surviving the next 100 years 
(Schulz and Hammond 2003, p. 1379). Although the conservation needs and 
biology of the Miami blue and Fender's blue are undoubtedly different, 
the two lycaenids share characteristics: both have limited dispersal, 
and most remaining habitat patches are completely isolated.
    Losses in diversity within historical and current populations of 
the Miami blue butterfly have already occurred. Historical populations 
were genetically more diverse than two contemporary populations (BHSP 
and KWNWR) (Saarinen 2009, p. 48). Yet together, between the two 
contemporary populations, the Miami blue had retained a significant 
amount of genetic diversity from its historical values

[[Page 49561]]

(Saarinen 2009, p. 51). Despite likely fluctuations in population size, 
the BHSP population had retained an adequate amount of genetic 
diversity to maintain the population (Saarinen 2009, p. 77). Overall, 
patterns of genetic diversity in the BHSP population (mean overall 
observed heterozygosity of 39.5 percent) were similar to or slightly 
lower than other nonmigratory butterfly species' studies utilizing 
microsatellite markers (Saarinen 2009, pp. 50, 74-75). Unfortunately, 
the BHSP population may now be lost. The extant KWNWR population is 
more genetically diverse (mean observed heterozygosity of 51 percent 
vs. 39.5 percent for BHSP) (Saarinen 2009, p. 75).
    The Miami blue appears to have been impacted by relative isolation. 
No gene flow has occurred between contemporary populations (Saarinen et 
al. 2009a, p. 36). Saarinen (2009, p. 79) suggests that the separation 
was recent. While historical populations may have once linked the two 
contemporary populations, the recent absence of populations between 
KWNWR and BHSP appears to have broken the gene flow (Saarinen 2009, p. 
79). Based upon modeling with a different butterfly species, Fleishman 
et al. (2002, pp. 706-716) argued that factors such as habitat quality 
may influence metapopulation dynamics, driving extinction and 
colonization processes, especially in systems that experience 
substantial natural and anthropogenic environmental variability (see 
Environmental stochasticity below).
    According to Saarinen et al. (2009a, p. 36), the severely reduced 
size of the existing populations suggests that genetic factors along 
with environmental stochasticity may already be affecting the 
persistence of the Miami blue. However, they also suggested that, in 
terms of extinction risk, a greater short-term problem for the two 
contemporary natural populations (BHSP and KWNWR) may be the lack of 
gene flow rather than the current effective population size (Saarinen 
et al. 2009a, p. 36). If only one or two metapopulations remain, it is 
absolutely critical that remaining genetic diversity and gene flow are 
retained. Conservation decisions to augment or reintroduce populations 
should not be made without careful consideration of habitat 
availability, genetic adaptability, the potential for the introduction 
of maladapted genotypes, and other factors (Frankham 2008, pp. 325-333; 
Saarinen et al. 2009a, p. 36).

Aspects of Its Natural History

    Aspects of the Miami blue's natural history may increase the 
likelihood of extinction. Cushman and Murphy (1993, p. 40) argued that 
dispersal is essential for the persistence of isolated populations. 
Input of individuals from neighboring areas can bolster dwindling 
numbers and provide an influx of genetic diversity, increasing fitness 
and population viability. The tendency for lycaenids to be 
comparatively sedentary should result in less frequent recolonization, 
less influx of individuals, and reduced gene flow between populations 
(Cushman and Murphy 1993, p. 40). In short, taxa with limited dispersal 
abilities may be far more susceptible to local extinction events than 
taxa with well-developed abilities (Cushman and Murphy 1993, p. 40).
    Lycaenids with a strong dependence on ants may be more sensitive to 
environmental changes and thus more prone to endangerment and 
extinction than species not tended by ants (and non-lycaenids in 
general) (Cushman and Murphy 1993, pp. 37, 41). Their hypothesis is 
based on the probability that the combination of both the right food 
plant and the presence of a particular ant species may occur relatively 
infrequently in the landscape. Selection may favor reduced dispersal by 
ant-associated lycaenids due to the difficulty associated with locating 
patches that contain the appropriate combination of food plants and 
ants (Cushman and Murphy 1993, pp. 39-40). Although significant 
research on the relationship between Miami blue larvae and ants has 
been conducted, this association is still not completely understood. 
Lycaenid traits (sedentary, host-specific, symbiotic with ants) that 
result in isolated populations of variable sizes may serve to limit 
genetic exchange (Cushman and Murphy 1993, pp. 37, 39-40). The Miami 
blue possesses several of these traits, all of which may increase 
susceptibility and contribute to imperilment.

Environmental Stochasticity

    The climate of the Keys is driven by a combination of local, 
regional, and global events, regimes, and oscillations. There are three 
main ``seasons'': (1) The wet season, which is hot, rainy, and humid 
from June through October, (2) the official hurricane season that 
extends one month beyond the wet season (June 1 through November 30) 
with peak season being August and September, and (3) the dry season, 
which is drier and cooler from November through May. In the dry season, 
periodic surges of cool and dry continental air masses influence the 
weather with short-duration rain events followed by long periods of dry 
    Environmental factors have likely impacted the Miami blue and its 
habitat within its historical range. A hard freeze in the late 1980s 
likely contributed to the Miami blue's decline (L. Koehn, pers. comm. 
2002) presumably due to loss of larval host plants in south Florida. 
Prolonged cold temperatures in January 2010 and December 2010 through 
January 2011 may have also impacted the remaining metapopulations in 
the Keys. Unseasonably cold temperatures during winter 2010 (in 
combination with impacts from iguanas) resulted in a substantial loss 
of nickerbean and nectar sources at BHSP. This reduction, albeit 
temporary, may have severely impacted an already depressed Miami blue 
population on the island. Similarly, extended dry conditions and 
drought can affect the availability of host plants and nectar sources 
and affect butterfly populations (Emmel and Daniels 2004, pp. 13-14, 
17). Depressed numbers of the Miami blue at BHSP in 2008 were 
attributed to severe drought (Emmel and Daniels 2009, p. 4).
    The Keys are regularly threatened by tropical storms and 
hurricanes. No area of the Keys is more than 20 feet (6.1 m) above sea 
level (and many areas are only a few feet (meters) in elevation). These 
tropical systems have affected the Miami blue and its habitat. Calhoun 
et al. (2002, p. 18) indicated that Hurricane Andrew in 1992 may have 
negatively impacted the majority of Miami blue populations in southern 
Florida. In 2005, four hurricanes (Katrina, Dennis, Rita, and Wilma) 
affected habitat at BHSP, resulting in reduced abundance of Miami blues 
following the storms that continued throughout 2006 (Salvato and 
Salvato 2007, p. 160) and beyond (Emmel and Daniels 2009, p. 4). A 
significant portion of the nickerbean and large stands of nectar plants 
at BHSP were temporarily damaged by the storms, including roughly 50 
percent of the vegetation on the southern side of the island (Salvato 
and Salvato 2007, p. 157). Although the host plant quickly recovered 
following the storms (Salvato and Salvato 2007, p. 160), the Miami blue 
never fully recolonized several parts of the island (Emmel and Daniels 
2009, p. 4).
    Similarly, Hurricane Wilma heavily damaged blackbead across many 
islands within KWNWR (Cannon et al. 2010, p. 850). Although the 
hurricane severely damaged or killed much of the Miami blue host plant 
on KWNWR, it is also believed to have enhanced or created many new 
habitats across the islands by clearing older vegetation and opening 
patches for growth of host plant and nectar sources (Cannon et al. 
2010, p.

[[Page 49562]]

852). Cannon et al. (2010, p. 852) suggest that the proximity and 
circular arrangement of these islands may provide some safeguard during 
mild or moderate storms. Given enough resiliency in extant populations, 
certain storm regimes may benefit populations over some timeframe if 
these events result in disturbances that favor host plants and other 
habitat components.
    According to the Florida Climate Center, Florida is by far the most 
vulnerable State in the United States to hurricanes and tropical storms 
(http://coaps.fsu.edu/climate_center/tropicalweather.shtml). Based on 
data gathered 1856-2008, Klotzbach and Gray (2009, p. 28) calculated 
the climatological and current-year probabilities for each State being 
impacted by a hurricane and major hurricane. Of the coastal States 
analyzed, Florida had the highest climatological probabilities, with a 
51 percent probability of a hurricane and a 21 percent probability of a 
major hurricane over a 52-year time span. Florida had a 45 percent 
current-year probability of a hurricane and an 18 percent current-year 
probability of a major hurricane (Klotzbach and Gray 2009, p. 28). 
Given the Miami blue's low population size and few isolated 
occurrences, the subspecies is at substantial risk from hurricanes, 
storm surges, or other extreme weather. Depending on the location and 
intensity of a hurricane or other severe weather event, it is possible 
that the Miami blue could be extirpated or could become extinct. 
Because it has poor dispersal capabilities, natural recolonization of 
potentially suitable sites is anticipated to be unlikely or exceedingly 
slow at best.
    Other processes to be affected by climate change include 
temperatures, rainfall (amount, seasonal timing, and distribution), and 
storms (frequency and intensity). Temperatures are predicted to rise 
from 2 [deg]C to 5 [deg]C for North America by the end of this century 
(IPCC 2007, pp. 7-9, 13). Based upon modeling, Atlantic hurricane and 
tropical storm frequencies are expected to decrease (Knutson et al. 
2008, pp. 1-21). By 2100, there should be a 10-30 percent decrease in 
hurricane frequency with a 5-10 percent wind increase. This is due to 
more hurricane energy available for intense hurricanes. However, 
hurricane frequency is expected to drop due to more wind shear impeding 
initial hurricane development. In addition to climate change, weather 
variables are extremely influenced by other natural cycles, such as El 
Ni[ntilde]o Southern Oscillation with a frequency of every 4-7 years, 
solar cycle (every 11 years), and the Atlantic Multi-decadal 
Oscillation. All of these cycles influence changes in Floridian 
weather. The exact magnitude, direction, and distribution of all of 
these changes at the regional level are difficult to predict.
    We have identified a wide array of natural or manmade factors 
affecting the continued existence of the Miami blue butterfly. These 
threats have operated in the past, are impacting the subspecies now, 
and will continue to impact the species in the foreseeable future. 
Based on our analysis of the best available information, we have no 
reason to believe that natural or manmade factors will change in the 
foreseeable future.

Determination of Status

    We have carefully assessed the best scientific and commercial 
information available regarding the past, present, and future threats 
to the Miami blue butterfly. The habitat and range of the subspecies 
are threatened with destruction, modification, and curtailment from 
human population growth, associated development and agriculture, and 
environmental effects resulting from climatic change. Due to the few 
metapopulations, small population size, restricted range, and 
remoteness of occupied habitat, collection is a significant threat to 
the subspecies and could potentially occur at any time. Additionally, 
the subspecies is currently threatened by a wide array of natural and 
manmade factors. Existing regulatory mechanisms do not provide adequate 
protection for the subspecies. As a result, impacts from increasing 
threats, singly or in combination, are likely to result in the 
extinction of the subspecies because the magnitude of threats is high.
    Section 3 of the Endangered Species Act defines an endangered 
species as ``* * * any species which is in danger of extinction 
throughout all or a significant portion of its range'' and a threatened 
species as ``* * * any species which is likely to become an endangered 
species within the foreseeable future throughout all or a significant 
portion of its range.'' Based on the immediate and ongoing significant 
threats to the Miami blue butterfly throughout its entire occupied 
range and the fact that the subspecies is restricted to only one or 
possibly two populations, we have determined that the subspecies is in 
danger of extinction throughout all of its range. Since threats extend 
throughout the entire range, it is unnecessary to determine if the 
Miami blue butterfly is in danger of extinction throughout a 
significant portion of its range. Therefore, on the basis of the best 
available scientific and commercial information, we have determined 
that the Miami blue butterfly meets the definition of an endangered 
species under the Act. Consequently, we are listing the Miami blue 
butterfly as an endangered species throughout its entire range.

Reasons for Emergency Determination

    Under section 4(b)(7) of the Act and regulations at 50 CFR 424.20, 
we may emergency list a species if the threats to the species 
constitute an emergency posing a significant risk to its well-being. 
Such an emergency listing expires 240 days following publication in the 
 Federal Register unless, during this 240-day period, we list the 
species following the normal listing procedures. Below, we discuss the 
reasons why emergency listing the Miami blue butterfly as endangered is 
warranted. In accordance with the Act, if at any time after we publish 
this emergency rule, we determine that substantial evidence does not 
exist to warrant such a rule, we will withdraw it.
    In making this determination, we have carefully assessed the best 
scientific and commercial information available regarding the past, 
present, and future threats faced by the Miami blue butterfly. The only 
confirmed metapopulation of Miami blue is currently restricted to a 
few, small insular areas in the extreme southern portion of its 
historical range. The range of this butterfly, which once extended from 
the Keys north along the Florida coasts to about St. Petersburg and 
Daytona, is now substantially reduced, with an estimated > 99 percent 
decline in area occupied. Population size is unknown, but estimated to 
be in the hundreds. Since only one or possibly two small 
metapopulations remain in KWNWR, the Miami blue butterfly is imminently 
threatened by its restricted range and the combined influences of 
habitat destruction or modification, impacts by iguanas, accidental 
harm from humans, loss of genetic heterogeneity, and catastrophic 
environmental events. Illegal collection could cause severe impacts, 
given the few populations and individuals remaining. Therefore, we find 
these threats constitute an immediate and significant risk to the well-
being of the species and that extinction of the Miami blue butterfly 
may occur at any time.
    We believe that the survival of the Miami blue now depends on 
protecting the species' occupied and suitable habitat from further 
degradation and fragmentation; restoring potentially suitable habitat 
within its historical range; removing and reducing threats from 
iguanas, pesticides, and accidental

[[Page 49563]]

harm from humans; increasing the current population in size; reducing 
the threats of illegal collection; retaining the remaining genetic 
diversity; and, establishing populations at additional locations. The 
survey and monitoring efforts and scientific studies conducted to date, 
when combined with other available historical information, make it 
clear that the Miami blue butterfly is on the brink of extinction.
    By emergency listing the Miami blue butterfly as an endangered 
subspecies, we believe the protections (through sections 7, 9, and 10 
of the Act) and recognition that immediately become available to the 
subspecies will increase the likelihood that it can be saved from 
extinction and ultimately be recovered. In addition, if protections 
remain in place after the 240-day period, recovery funds may become 
available, which could facilitate recovery actions (e.g., funding for 
additional surveys, management needs, research, captive propagation and 
reintroduction, monitoring) (see Available Conservation Measures).
    The Service acknowledges that it cannot fully address some of the 
natural threats facing the subspecies (e.g., hurricanes, tropical 
storms) or even some of the other significant, long-term threats (e.g., 
climatic changes, sea-level rise). However, through emergency listing, 
we provide immediate protection to the known population(s) and any new 
population of the subspecies that may be discovered (see section 9 of 
Available Conservation Measures below). With emergency listing, we can 
also influence Federal actions that may potentially impact the 
subspecies (see section 7 below); this is especially valuable if it is 
found at additional locations. With emergency listing, we are also 
better able to deter illicit collection and trade.
    Through this action, the Miami blue and the three butterflies that 
are similar in appearance will receive immediate protection from 
collection, possession, and trade (through sections 9 and 10 of the 
Act). At present, the three similar butterflies are not protected by 
the State. Extending the prohibitions of collection, possession, and 
trade to the three similar butterflies provides greater protection to 
the Miami blue. This immediate protection will help to deter those who 
might otherwise seek to collect the Miami blue before a proposed rule 
could be finalized (i.e., through the normal listing process). At this 
time, the normal listing timeframe and process is insufficient to 
prevent losses that may result in extinction. We believe emergency 
listing will partially alleviate some of the imminent threats that now 
pose a significant risk to the survival of the subspecies.

Available Conservation Measures

    Conservation measures provided to species listed as endangered or 
threatened under the Act include recognition, recovery actions, 
requirements for Federal protection, and prohibitions against certain 
practices. Recognition through listing results in public awareness and 
conservation by Federal, State, Tribal, and local agencies, private 
organizations, and individuals. The Act encourages cooperation with the 
States and requires that recovery actions be carried out for all listed 
species. The protection required by Federal agencies and the 
prohibitions against certain activities are discussed, in part, below.
    The primary purpose of the Act is the conservation of endangered 
and threatened species and the ecosystems upon which they depend. The 
ultimate goal of such conservation efforts is the recovery of these 
listed species, so that they no longer need the protective measures of 
the Act. Subsection 4(f) of the Act requires the Service to develop and 
implement recovery plans for the conservation of endangered and 
threatened species. The recovery planning process involves the 
identification of actions that are necessary to halt or reverse the 
species' decline by addressing the threats to its survival and 
recovery. The goal of this process is to restore listed species to a 
point where they are secure, self-sustaining, and functioning 
components of their ecosystems.
    Recovery planning includes the development of a recovery outline 
shortly after a species is listed, preparation of a draft and final 
recovery plan, and revisions to the plan as significant new information 
becomes available. The recovery outline guides the immediate 
implementation of urgent recovery actions and describes the process to 
be used to develop a recovery plan. The recovery plan identifies site-
specific management actions that will achieve recovery of the species, 
measurable criteria that determine when a species may be downlisted or 
delisted, and methods for monitoring recovery progress. Recovery plans 
also establish a framework for agencies to coordinate their recovery 
efforts and provide estimates of the cost of implementing recovery 
tasks. Recovery teams (composed of species experts, Federal and State 
agencies, nongovernment organizations, and stakeholders) are often 
established to develop recovery plans. When completed, the recovery 
outline, draft recovery plan, and the final recovery plan will be 
available on our Web site (http://www.fws.gov/endangered), or from our 
South Florida Ecological Services Field Office (see FOR FURTHER 
    Implementation of recovery actions generally requires the 
participation of a broad range of partners, including other Federal 
agencies, States, Tribes, nongovernmental organizations, businesses, 
and private landowners. Examples of recovery actions include habitat 
restoration (e.g., restoration of native vegetation), research, captive 
propagation and reintroduction, and outreach and education. The 
recovery of many listed species cannot be accomplished solely on 
Federal lands because their range may occur primarily or solely on non-
Federal lands. To achieve recovery of these species requires 
cooperative conservation efforts on private, State, and Tribal lands.
    Through this listing, funding for recovery actions will be 
available from a variety of sources, including Federal budgets, State 
programs, and cost share grants for non-Federal landowners, the 
academic community, and nongovernmental organizations. Additionally, 
under section 6 of the Act, we would be able to grant funds to the 
State of Florida for management actions promoting the conservation of 
the Miami blue. Information on our grant programs that are available to 
aid species recovery can be found at: http://www.fws.gov/grants.
    Please let us know if you are interested in participating in 
recovery efforts for the Miami blue. Additionally, we invite you to 
submit any new information on the subspecies, its habitat, or threats 
whenever it becomes available and any information you may have for 
recovery planning purposes; if you submit information after the date 
listed in the DATES section above, you will need to send it to the 
street address provided in the FOR FURTHER INFORMATION CONTACT section.
    Section 7(a) of the Act requires Federal agencies to evaluate their 
actions with respect to any species that is proposed or listed as 
endangered or threatened and with respect to its critical habitat, if 
any is being designated. Regulations implementing this interagency 
cooperation provision of the Act are codified at 50 CFR part 402. 
Section 7(a)(4) requires Federal agencies to confer informally with us 
on any action that is likely to jeopardize the continued existence of a 
species proposed for listing or result in destruction or adverse 
modification of proposed critical habitat. If a species is listed 
subsequently, section 7(a)(2) of the Act requires Federal agencies to

[[Page 49564]]

ensure that activities they authorize, fund, or carry out are not 
likely to jeopardize the continued existence of such a species or to 
destroy or adversely modify its critical habitat. If a Federal action 
may affect a listed species or its critical habitat, the responsible 
Federal agency must enter into formal consultation with us.
    Federal agency actions that may require conference or consultation 
as described in the preceding paragraph include the issuance of Federal 
funding, permits, or authorizations for construction, clearing, 
development, road maintenance, pesticide registration, pesticide use 
(on Federal land or with Federal funding), agricultural assistance 
programs, Federal loan and insurance programs, Federal habitat 
restoration programs, and scientific and special uses. Activities will 
trigger consultation under section 7 of the Act if they may affect the 
Miami blue butterfly, as addressed in this emergency rule.

Jeopardy Standard

    Prior to and following listing, the Service applies an analytical 
framework for jeopardy analyses that relies heavily on the importance 
of core area populations to the survival and recovery of the species. 
The section 7(a)(2) analysis is focused not only on these populations 
but also on the habitat conditions necessary to support them.
    The jeopardy analysis usually expresses the survival and recovery 
needs of the species in a qualitative fashion without making 
distinctions between what is necessary for survival and what is 
necessary for recovery. Generally, if a proposed Federal action is 
incompatible with the viability of the affected core area 
population(s), inclusive of associated habitat conditions, a jeopardy 
finding is considered to be warranted, because of the relationship of 
each core area population to the survival and recovery of the species 
as a whole.

Section 9 Take

    The Act and implementing regulations set forth a series of general 
prohibitions and exceptions that apply to all endangered and threatened 
wildlife. These prohibitions are applicable to the Miami blue butterfly 
immediately through emergency listing. The prohibitions of section 
9(a)(2) of the Act, codified at 50 CFR 17.21 for endangered wildlife, 
in part, make it illegal for any person subject to the jurisdiction of 
the United States to take (includes harass, harm, pursue, hunt, shoot, 
wound, kill, trap, capture, or collect, or to attempt any of these), 
import or export, deliver, receive, carry, transport, or ship in 
interstate or foreign commerce in the course of commercial activity, or 
sell or offer for sale in interstate or foreign commerce any listed 
species. It also is illegal to possess, sell, deliver, carry, 
transport, or ship any such wildlife that has been taken illegally. 
Further, it is illegal for any person to attempt to commit, to solicit 
another person to commit, or to cause to be committed, any of these 
acts. Certain exceptions apply to our agents and State conservation 
    We may issue permits to carry out otherwise prohibited activities 
involving endangered wildlife under certain circumstances. We codified 
the regulations governing permits for endangered species at 50 CFR 
17.22. Such permits are available for scientific purposes, to enhance 
the propagation or survival of the species, or for incidental take in 
the course of otherwise lawful activities.
    It is our policy, published in the Federal Register on July 1, 1994 
(59 FR 34272), to identify, to the maximum extent practicable at the 
time a species is listed, those activities that would or would not 
constitute a violation of section 9 of the Act and associated 
regulations at 50 CFR 17.21. The intent of this policy is to increase 
public awareness of the effect of this emergency listing on proposed 
and ongoing activities within a species' range. We believe, based on 
the best available information, that the following actions will not 
result in a violation of the provisions of section 9 of the Act, 
provided these actions are carried out in accordance with existing 
regulations and permit requirements, if applicable:
    (1) Possession, delivery, or movement, including interstate 
transport and import into or export from the United States, involving 
no commercial activity, of dead specimens of this taxon that were 
collected or legally acquired prior to the effective date of this rule.
    (2) Actions that may affect the Miami blue that are authorized, 
funded, or carried out by Federal agencies when such activities are 
conducted in accordance with an incidental take statement issued by us 
under section 7 of the Act.
    (3) Actions that may affect the Miami blue that are not authorized, 
funded, or carried out by a Federal agency, when the action is 
conducted in accordance with an incidental take permit issued by us 
under section 10(a)(1)(B) of the Act. Applicants design a Habitat 
Conservation Plan (HCP) and apply for an incidental take permit. These 
HCPs are developed for species listed under section 4 of the Act and 
are designed to minimize and mitigate impacts to the species to the 
greatest extent practicable.
    (4) Actions that may affect the Miami blue that are conducted in 
accordance with the conditions of a section 10(a)(1)(A) permit for 
scientific research or to enhance the propagation or survival of the 
    (5) Captive propagation activities involving the Miami blue that 
are conducted in accordance with the conditions of a section 
10(a)(1)(A) permit, our ``Policy Regarding Controlled Propagation of 
Species Listed Under the Endangered Species Act,'' and in cooperation 
with the State of Florida.
    (6) Low-impact, infrequent, dispersed human activities on foot 
(e.g., bird watching, butterfly watching, sightseeing, backpacking, 
photography, camping, hiking) in areas occupied by the Miami blue or 
where its host and nectar plants are present.
    (7) Activities on private lands that do not result in take of the 
Miami blue butterfly, such as normal landscape activities around a 
personal residence, construction that avoids butterfly habitat, and 
pesticide/herbicide application consistent with label restrictions, if 
applied in areas where the subspecies is absent.
    We believe the following activities would be likely to result in a 
violation of section 9 of the Act; however, possible violations are not 
limited to these actions alone:
    (1) Unauthorized possession, collecting, trapping, capturing, 
killing, harassing, sale, delivery, or movement, including interstate 
and foreign commerce, or harming or attempting any of these actions, of 
Miami blue butterflies at any life stage without a permit (research 
activities where Miami blue butterflies are surveyed, captured 
(netted), or collected will require a permit under section 10(a)(1)(A) 
of the Act).
    (2) Incidental take of Miami blue butterfly without a permit 
pursuant to section 10 (a)(1)(B) of the Act.
    (3) Sale or purchase of specimens of this taxon, except for 
properly documented antique specimens of this taxon at least 100 years 
old, as defined by section 10(h)(1) of the Act.
    (4) Unauthorized destruction or alteration of Miami blue butterfly 
habitat (including unauthorized grading, leveling, plowing, mowing, 
burning, trampling, herbicide spraying, or other destruction or 
modification of occupied or potentially occupied habitat or pesticide 
application in known occupied habitat) in ways that kills or injures 
eggs, larvae, or adult Miami blue

[[Page 49565]]

butterflies by significantly impairing the subspecies' essential 
breeding, foraging, sheltering, or other essential life functions.
    (5) Use of pesticides/herbicides that are in violation of label 
restrictions resulting in take of Miami blue butterfly or ants 
associated with the subspecies in areas occupied by the butterfly.
    (6) Unauthorized release of biological control agents that attack 
any life stage of this taxon or ants associated with the Miami blue.
    (7) Removal or destruction of native food plants being utilized by 
Miami blue butterfly, including Caesalpinia spp., Cardiospermum spp., 
and Pithecellobium spp., within areas used by this taxon that results 
in harm to this butterfly.
    (8) Release of exotic species into occupied Miami blue butterfly 
habitat that may displace the Miami blue or its native host plants.
    We will review other activities not identified above on a case-by-
case basis to determine whether they may be likely to result in a 
violation of section 9 of the Act. We do not consider these lists to be 
exhaustive, and provide them as information to the public.
    You should direct questions regarding whether specific activities 
may constitute a future violation of section 9 of the Act to the Field 
Supervisor of the Service's South Florida Ecological Services Field 
Office (see FOR FURTHER INFORMATION CONTACT). Requests for copies of 
regulations regarding listed species and inquiries about prohibitions 
and permits should be addressed to the U.S. Fish and Wildlife Service, 
Ecological Services Division, Endangered Species Permits, 1875 Century 
Boulevard, Atlanta, GA 30345 (Phone 404-679-7313; Fax 404-679-7081).

Critical Habitat and Prudency Determination

    Critical habitat and prudency is addressed in the proposed listing 
rule, which is published concurrently with this emergency rule. In that 
rule, we determine that designation of critical habitat for the Miami 
blue butterfly is not prudent due to the increased likelihood and 
severity of threats to the subspecies from collection and destruction 
of sensitive habitat. Spatially depicting exactly where the subspecies 
may or could be found and more widely publicizing maps of specific 
areas containing essential features or essential areas is expected to 
expose the fragile population and its habitat to greater risks. In 
addition, designation of critical habitat will likely exacerbate 
enforcement problems.

Similarity of Appearance

    Section 4(e) of the Act authorizes the treatment of a species, 
subspecies, or population segment as endangered or threatened if: ``(a) 
Such species so closely resembles in appearance, at the point in 
question, a species which has been listed pursuant to such section that 
enforcement personnel would have substantial difficulty in attempting 
to differentiate between the listed and unlisted species; (b) the 
effect of this substantial difficulty is an additional threat to an 
endangered or threatened species; and (c) such treatment of an unlisted 
species will substantially facilitate the enforcement and further the 
policy of this Act.'' Listing a species as endangered or threatened 
under the similarity of appearance provisions of the Act extends the 
take prohibitions of section 9 of the Act to cover the species. A 
designation of endangered or threatened due to similarity of appearance 
under section 4(e) of the Act, however, does not extend other 
protections of the Act, such as consultation requirements for Federal 
agencies under section 7 and the recovery planning provisions under 
section 4(f), that apply to species that are listed as endangered or 
threatened under section 4(a). All applicable prohibitions and 
exceptions for species listed under section 4(e) of the Act due to 
similarity of appearance to a threatened or endangered species will be 
set forth in a special rule under section 4(d) of the Act.
    There are only slight morphological differences between the Miami 
blue and the cassius blue, ceraunus blue, and nickerbean blue, making 
it difficult to differentiate between the species, especially due to 
their small size. This poses a problem for Federal and State law 
enforcement agents trying to stem illegal collection and trade in the 
Miami blue. It is quite possible that collectors authorized to collect 
similar species may inadvertently (or purposefully) collect the Miami 
blue butterfly thinking it was the cassius blue, ceraunus blue, or 
nickerbean blue, which also occur in the same geographical area and 
habitat type. The listing of these similar blue butterflies as 
threatened due to similarity of appearance eliminates the ability of 
amateur butterfly enthusiasts and private and commercial collectors to 
purposefully or accidentally misrepresent the Miami blue as one of 
these other species. The listing will also facilitate Federal and State 
law enforcement agents' efforts to curtail illegal possession, 
collection, and trade in the Miami blue. At this time, the three 
similar butterflies are not protected by the State. Extending the 
prohibitions of collection, possession, and trade to the three similar 
butterflies through this listing of these species due to similarity of 
appearance under section 4(e) of the Act and providing applicable 
prohibitions and exceptions under section 4(d) of the Act will provide 
greater protection to the Miami blue. For these reasons, we are listing 
the cassius blue butterfly (Leptotes cassius theonus), ceraunus blue 
butterfly (Hemiargus ceraunus antibubastus), and nickerbean blue 
butterfly (Cyclargus ammon) as threatened due to similarity of 
appearance to the Miami blue, pursuant to section 4(e) of the Act.

Special Rule Under Section 4(d) of the Act

    Whenever a species is listed as a threatened species under the Act, 
the Secretary may specify regulations that he deems necessary and 
advisable to provide for the conservation of that species under the 
authorization of section 4(d) of the Act. These rules, commonly 
referred to as ``special rules,'' are found in part 17 of title 50 of 
the Code of Federal Regulations (CFR) in sections 17.40-17.48. This 
special rule for 17.47, which is reserved, prohibits take of any 
cassius blue butterfly (Leptotes cassius theonus), ceraunus blue 
butterfly (Hemiargus ceraunus antibubastus), or nickerbean blue 
butterfly (Cyclargus ammon) or their immature stages throughout their 
ranges in order to protect the Miami blue butterfly from collection, 
possession, and trade. In this context, collection and trade are 
defined as any activity where cassius blue, ceraunus blue, or 
nickerbean blue butterflies or their immature stages are attempted to 
be, or are intended to be, kept, traded, sold, or exchanged for goods 
or services. Capture of cassius blue, ceraunus blue, or nickerbean blue 
butterflies, or their immature stages, is not prohibited if it is 
accidental or incidental to otherwise legal collection activities, such 
as research, provided the animal is released immediately upon discovery 
at the point of capture. Scientific activities involving collection or 
propagation of these similarity of appearance butterflies are not 
prohibited provided there is prior written authorization from the 
Service. All otherwise legal activities involving cassius blue, 
ceraunus blue, or nickerbean blue butterflies that are conducted in 
accordance with applicable State, Federal, Tribal, and local laws and 
regulations are not considered to be take under this regulation.

[[Page 49566]]

Effects of These Rules

    Listing the cassius blue, ceraunus blue, and nickerbean blue 
butterflies as threatened under the ``similarity of appearance'' 
provisions of the Act, and the promulgation of a special rule under 
section 4(d) of the Act, extend take prohibitions to these species and 
their immature stages. Capture of these species, including their 
immature stages, is not prohibited if it is accidental or incidental to 
otherwise legal collection activities, such as research, provided the 
animal is released immediately upon discovery, at the point of capture. 
However, this emergency rule establishes immediate prohibitions on the 
possession, collection, and trade of these species throughout their 
ranges in the United States. Likewise, this emergency rule immediately 
prohibits the import and export of these subspecies, and therefore may 
have an effect on commercial and non-commercial trade within the United 
    There are over 60 species and subspecies of butterflies within the 
Cyclargus, Leptotes, Hemiargus and Pseudochrysops genera, occurring 
domestically and internationally, that could be confused with the Miami 
blue butterfly, or the three similarity of appearance butterflies. We 
are aware that legal trade in some of these other blue butterflies 
exists. To avoid confusion and delays in legal trade, we strongly 
recommend maintaining the appropriate documentation and declarations 
with legal specimens at all times, especially when importing them into 
the United States. Legal trade of other species that may be confused 
with the Miami blue butterfly or the three similarity of appearance 
butterflies should also comply with the import/export transfer 
regulations under 50 CFR 14, where applicable.
    All otherwise legal activities that may involve incidental take 
(take that results from, but is not the purpose of, carrying out an 
otherwise lawful activity) of these similar butterflies, and which are 
conducted in accordance with applicable State, Federal, Tribal, and 
local laws and regulations, will not be considered take under this 
regulation. For example, this special 4(d) rule exempts legal 
application of pesticides, yard care, vehicle use, vegetation 
management, exotic plant removal, burning, and any other legally 
undertaken actions that result in the accidental take of cassius blue, 
ceraunus blue, or nickerbean blue butterflies. These actions will not 
be considered as violations of section 9 of the Act. We believe that 
listing the cassius blue, ceraunus blue, and nickerbean blue 
butterflies under the similarity of appearance provision of the Act, 
coupled with this special 4(d) rule, will help minimize enforcement 
problems and enhance conservation of the Miami blue.
    We believe that this provision to allow incidental take of these 
three similar butterflies will not pose a threat to the Miami blue 
because: (1) Activities such as yard care and vegetation control in 
developed or commercial areas that are likely to result in take of the 
cassius blue, ceraunus blue, and nickerbean blue are not likely to 
affect the Miami blue, and (2) the primary threat that activities 
concerning the cassius blue, ceraunus blue, and nickerbean blue 
butterflies pose to the Miami blue comes from collection and commercial 

Required Determinations

Clarity of Rule

    We are required by Executive Orders 12866 and 12988 and by the 
Presidential Memorandum of June 1, 1998, to write all rules in plain 
language. This means that each rule we publish must: (a) Be logically 
organized; (b) Use the active voice to address readers directly; (c) 
Use clear language rather than jargon; (d) Be divided into short 
sections and sentences; and (e) Use lists and tables wherever possible.
    If you feel that we have not met these requirements, send us 
comments by one of the methods listed in the ADDRESSES section. To 
better help us revise the rule, your comments should be as specific as 
possible. For example, you should tell us page numbers and the names of 
the sections or paragraphs that are unclearly written, which sections 
or sentences are too long, the sections where you feel lists or tables 
would be useful, etc.

Paperwork Reduction Act (44 U.S.C. 3501, et seq.)

    This rule does not contain any new collections of information that 
require approval by the Office of Management and Budget (OMB) under the 
Paperwork Reduction Act. This rule will not impose new recordkeeping or 
reporting requirements on State or local governments, individuals, 
businesses, or organizations. We may not conduct or sponsor, and you 
are not required to respond to, a collection of information unless it 
displays a currently valid OMB control number.

National Environmental Policy Act (42 U.S.C. 4321 et seq.)

    We have determined that we do not need to prepare an environmental 
assessment, as defined under the authority of the National 
Environmental Policy Act of 1969, in connection with regulations 
adopted under section 4(a) of the Act. We published a notice outlining 
our reasons for this determination in the  Federal Register on October 
25, 1983 (48 FR 49244).

References Cited

    A complete list of all references cited in this rule is available 
on the Internet at http://www.regulations.gov or upon request from the 
Field Supervisor, South Florida Ecological Services Office (see FOR 


    The primary author of this emergency rule is the staff of the South 
Florida Ecological Services Office (see FOR FURTHER INFORMATION 

List of Subjects in 50 CFR Part 17

    Endangered and threatened species, Exports, Imports, Reporting and 
recordkeeping requirements, Transportation.
Regulation Promulgation
    Accordingly, we amend part 17, subchapter B of chapter I, title 50 
of the Code of Federal Regulations, as follows:


1. The authority citation for part 17 continues to read as follows:

    Authority:  16 U.S.C. 1361-1407; 16 U.S.C. 1531-1544; 16 U.S.C. 
4201-4245; Public Law 99-625, 100 Stat. 3500; unless otherwise 

2. Amend Sec.  17.11(h) by adding new entries for the following, in 
alphabetical order under Insects, to the List of Endangered and 
Threatened Wildlife:

Sec.  17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

[[Page 49567]]

                          Species                                                    Vertebrate
------------------------------------------------------------                         population
                                                                                       where                                      Critical     Special
                                                                Historic  range      endangered       Status       When listed    habitat       rules
            Common name                  Scientific name                                 or
                                                                      * * * * * * *
                                                                      * * * * * * *
Butterfly, cassius blue............  Leptotes cassius        U.S.A. (FL), Bahamas,           NA  T(S/A)            ...........           NA     17.47(a)
                                      theonus.                Greater Antilles,
                                                              Cayman Islands.
Butterfly, ceraunus blue...........  Hemiargus ceraunus      U.S.A. (FL), Bahamas.           NA  T(S/A)            ...........           NA     17.47(a)
                                                                      * * * * * * *
Butterfly, Miami blue..............  Cyclargus thomasi       U.S.A. (FL), Bahamas.           NA  E                 ...........           NA           NA
                                                                      * * * * * * *
Butterfly, nickerbean blue.........  Cyclargus ammon.......  U.S.A. (FL), Bahamas,           NA  T(S/A)            ...........           NA     17.47(a)
                                                                      * * * * * * *

3. In subpart D, add Sec.  17.47 to read as follows:

Sec.  17.47  Special rules--insects.

    (a) Cassius blue butterfly (Leptotes cassius theonus), Ceraunus 
blue butterfly (Hemiargus ceraunus antibubastus), and Nickerbean blue 
butterfly (Cyclargus ammon).
    (1) All provisions of Sec.  17.31 apply to these species (cassius 
blue butterfly, ceraunus blue butterfly, nickerbean blue butterfly), 
regardless of whether in the wild or in captivity, and also apply to 
the progeny of any such butterfly.
    (2) Any violation of State law will also be a violation of the Act.
    (3) Incidental take, that is, take that results from, but is not 
the purpose of, carrying out an otherwise lawful activity, will not 
apply to the cassius blue butterfly, ceraunus blue butterfly, and 
nickerbean blue butterfly.
    (b) [Reserved]

    Dated: July 27, 2011.
Gregory E. Siekaniec,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. 2011-19812 Filed 8-9-11; 8:45 am]