[Federal Register Volume 63, Number 7 (Monday, January 12, 1998)]
[Proposed Rules]
[Pages 1807-1811]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-622]


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DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

50 CFR Parts 222 and 227

[Docket No. 971223310-7310-01; I.D. 101194C]


Endangered and Threatened Species; Withdrawal of Proposed Rule to 
List Snake River Spring/Summer Chinook Salmon and Fall Chinook Salmon 
as Endangered

AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and 
Atmospheric Administration (NOAA), Commerce.

ACTION: Proposed rule; withdrawal.

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SUMMARY: NMFS is withdrawing the proposed rule which published on 
December 28, 1994, to reclassify Snake River spring/summer chinook 
salmon (Oncorhynchus tshawytscha) and Snake River fall chinook salmon 
(O. tshawytscha) from threatened to endangered under the Endangered 
Species Act of 1973 (ESA). Events have taken place since the proposal 
that make the reclassification action unnecessary. Increasing 
abundance, combined with the effects of improved management, indicate 
that the risks facing these species are now lower than they were at the 
time of the proposal. While the status of these species has improved 
since the proposal, conservation efforts must continue to recover Snake 
River chinook salmon to sustainable levels.

DATES: This proposed rule is withdrawn on January 12, 1998.

ADDRESSES: Environmental and Technical Services Division, NMFS, 
Northwest Region, 525 NE Oregon Street--Suite 500, Portland, OR 97232-
2737.

FOR FURTHER INFORMATION CONTACT: Garth Griffin, NMFS, Protected 
Resources Division, Northwest Region, telephone (503) 231-2005, or Joe 
Blum, NMFS, Office of Protected Resources, telephone (301) 713-1401.

SUPPLEMENTARY INFORMATION:

Background

    In response to a June 1990 petition to list under the ESA Snake 
River chinook salmon, NMFS prepared status review reports for Snake 
River spring and summer chinook salmon (Matthews and Waples, 1991) and 
Snake River fall chinook salmon (Waples et al., 1991) providing 
detailed information, discussion, and references relevant to the level 
of risk faced by the species, including historical and current 
abundance, population trends, distribution of fish in space and time, 
and other information indicative of the health of the population.
    NMFS proposed listing Snake River spring/summer chinook salmon (56 
FR 29542) and Snake River fall chinook salmon (56 FR 29547) as 
threatened on June 27, 1991. The final determination listing Snake 
River spring/summer chinook salmon and Snake River fall chinook salmon 
as threatened was published on April 22, 1992 (57 FR 14653), and 
corrected on June 3, 1992 (57 FR 23458). The decision to list was based 
in part on a determination that the populations constituted 
evolutionarily significant units (ESUs) pursuant to NMFS' policy on 
applying the ESA species definition to Pacific salmon published on 
November 20, 1991 (56 FR 58612). Critical habitat was designated for 
Snake River spring/summer chinook salmon and Snake River fall chinook 
salmon on December 28, 1993 (58 FR 68543).
    In an emergency rule published in the Federal Register on August 
18, 1994 (59 FR 42529), NMFS determined that the status of Snake River 
spring/summer chinook salmon and the status of Snake River fall chinook 
salmon warranted reclassification to endangered, based on projected 
declines and continued low abundance levels of adult chinook salmon. 
Under the ESA (16 U.S.C. 1533(b)(7)) and its implementing regulations 
at 50 CFR 424.20(a), an emergency rule ceases to have force after 240 
days unless additional actions are taken.
    NMFS published a proposed rule to reclassify Snake River spring/
summer and Snake River fall chinook salmon as endangered on December 
28, 1994 (59 FR 66784), and solicited comments from peer reviewers, the 
public, and interested parties.
    After the proposed reclassification, a moratorium on listing 
actions was enacted by Congress which precluded work on this action. As 
a result of the moratorium and associated delays in its listing 
actions, NMFS prioritized its pending listing actions, with 
reclassifications receiving a low priority. NMFS has now assessed 
comments and information received in response to the proposed rule. A 
summary of this information, along with NMFS' analysis and conclusions 
follows.

Summary of Comments

    One hundred fifty-four written comments were received in response 
to the proposed rule to reclassify Snake River chinook salmon as 
endangered. NMFS has considered all comments received, including oral 
testimony from two public hearings (60 FR 7744, February 9, 1995) on 
the proposal. The majority of comments received voiced opposition to 
the proposed rule on the basis of potential economic impacts of the 
designation and questions regarding NMFS' jurisdiction over Snake River 
spring/summer and fall chinook salmon. Only four of these comments 
contained information of a technical nature relevant to NMFS' status 
determination. Several commenters provided information pertinent to 
research needs and recovery planning; information of this type will be 
addressed in the

[[Page 1808]]

recovery plan for these species and is not addressed here.
    Under a joint U.S. Fish and Wildlife Service/NMFS policy published 
July 1, 1994 (59 FR 34270), NMFS solicits the expert opinion of three 
appropriate and independent specialists regarding the pertinent 
scientific or commercial data and assumptions relating to the taxonomy, 
population models, and supportive biological and ecological information 
for species under consideration for listing. Accordingly, NMFS 
solicited independent review from the following experts: Dr. Lyle 
Calvin, Oregon State University; Dr. Jack Stanford, University of 
Montana; and Dr. Ray Hilborn, University of Washington. Comments were 
received from Dr. Stanford regarding the proposed rule.

Consideration of Economic and Jurisdictional Factors

    Comment: Numerous commenters stated that the potential economic 
impacts of these Snake River spring/summer and fall chinook salmon 
listings have not been properly addressed.
    Response: In determining whether to list a species as threatened or 
endangered, ESA implementing regulations 50 CFR 424.11(b) clearly state 
that such decisions must be made ``solely on the basis of the best 
available scientific and commercial information regarding a species' 
status, without reference to possible economic or other impacts of such 
a determination.'' Therefore, in making its listing determination, NMFS 
did not consider the economic impacts associated with the listing 
action. However, during the process of designating critical habitat and 
identifying recovery measures, economic considerations are (and have 
been) taken into account. With regard to Snake River spring/summer and 
fall chinook salmon, descriptions of such analyses can be found in the 
final rule designating critical habitat published on December 28, 1993 
(58 FR 68543).
    Comment: Numerous commenters questioned NMFS' jurisdiction in 
dealing with matters in the state of Idaho.
    Response: Under section 4(a)(1) of the ESA, the Secretary of 
Interior and the Secretary of Commerce (Secretaries) have authority to 
implement the ESA to protect and conserve threatened and endangered 
species. Authority for commercial fishery species (i.e., salmon 
species) management was transferred to the Department of Commerce from 
the Department of Interior under Reorganization Plan No. 4 of 1970. 
Therefore, based on the ESA and this Reorganization Plan, NMFS retains 
ESA jurisdiction over Snake River spring/summer and fall chinook 
salmon.

Consideration as a Species

    Comment: Several commenters contended that Snake River spring/
summer and fall chinook salmon are likely to be ``subspecies'' of a 
species which is abundant in other portions of its range. Therefore, 
neither Snake River spring/summer nor fall chinook salmon should be 
considered a ``species'' under the ESA.
    Response: In the final determination listing Snake River spring/
summer and fall chinook as threatened under the ESA (57 FR 14653, April 
22, 1992), NMFS determined that Snake River spring/summer and fall 
chinook salmon constitute ``species'' under the ESA. The present 
determination has no effect on the earlier determination. Section 3(15) 
of the ESA defines a ``species'' as including ``any subspecies of fish 
or wildlife or plants, and any distinct population segment of any 
species of vertebrate fish or wildlife which interbreeds when mature.'' 
NMFS' final policy on how it will apply the ESA ``species'' definition 
in evaluating Pacific salmon was published on November 20, 1991 (56 FR 
58612).
    Further guidance on the application of this policy is contained in 
the NMFS policy paper ``Pacific Salmon and the Definition of 'Species'' 
Under the Endangered Species Act'' (Waples 1991). NMFS' determination 
is consistent with this policy and guidance.

Factors Contributing to the Decline of Snake River Spring/Summer 
and Fall Chinook Salmon

    Comment: The majority of commenters identified specific factors 
that they believe to be responsible for causing the decline of these 
species. Many contended that mortality associated with dams on the 
Columbia and Snake Rivers has been the primary cause for decline, while 
others identified poor ocean conditions, in-river harvest, and 
predation as major factors for decline. Several commenters took 
exception to NMFS identifying mining as a factor for the species' 
decline.
    Response: NMFS agrees that there are a variety of factors which 
have contributed to the decline of these species. In the proposed rule 
to reclassify Snake River spring/summer and fall chinook as endangered 
(59 FR 66784, December 28, 1994), NMFS identified a range of factors 
which have contributed to the decline of these species including: 
Hydropower development, water withdrawal and storage, irrigation 
diversions, siltation and pollution from sewage, farming, grazing, 
logging, mining, harvest and hatchery impacts, predation, and drought. 
NMFS recognizes that, for some of these human-induced factors, steps 
have been taken by Federal, state, and private entities to identify and 
reduce adverse impacts on Snake River chinook salmon. NMFS is hopeful 
that continued attention to these factors will ultimately result in the 
recovery of Snake River chinook salmon.
    Comment: Numerous commenters insisted that declines in Snake River 
spring/summer and fall chinook salmon have occurred as a result of 
natural evolutionary processes.
    Response: The proposed rule to reclassify Snake River spring/summer 
and fall chinook salmon from threatened to endangered was based on the 
biological status of the species. Assessing the source or cause (either 
natural or manmade) of a species' decline does not affect the outcome 
of NMFS' status determination but, instead, focuses remedial action on 
those factors which contribute to the threat to the species. With 
respect to the commenters' concern, NMFS is unaware of scientific 
research which supports the claim that these species have declined 
primarily as a result of natural evolutionary processes. Available 
research has documented that mortality resulting from human activities 
has significantly contributed to the decline of these species. 
Therefore, NMFS believes that human activities, and not natural 
evolutionary processes, are the primary factors which have led to the 
decline of Snake River chinook salmon.

Existing Regulatory Mechanisms

    Comment: Several commenters contended that existing state and 
Federal regulations are sufficient to guarantee that no adverse impacts 
to water quality or habitat will occur in the Snake River basin. 
Similarly, several commenters stated that management practices have 
improved such that further degradation of salmon habitat will not 
occur.
    Response: NMFS believes that, since Snake River spring/summer and 
fall chinook salmon were proposed for reclassification as endangered 
species, progress has been made in improving salmon management, 
passage, harvest, and habitat conditions in the Columbia and Snake 
River systems. All of these improvements have likely resulted in 
increased survival by juvenile and adult Snake River chinook salmon. 
Further discussion of this issue is provided

[[Page 1809]]

under ``Summary of Factors Affecting the Species.''

Evaluating the Status of Snake River Spring/Summer and Fall Chinook 
Salmon

    The state of Alaska, Department of Fish and Game (ADFG) submitted a 
report which addresses several issues pertaining to the proposed 
reclassification of Snake River fall chinook salmon (ADFG, 1995). In 
its report, ADFG asserts that an analysis of the following factors 
should occur prior to reclassification: escapement, likelihood of 
extinction, probability of persistence with respect to survival, 
spawner/recruit relationship, and forecasts of adult returns. These 
comments also apply to the proposed reclassification of Snake River 
spring/summer chinook salmon since similar risk assessment methods were 
used for this species. A discussion of the major points in the comments 
submitted by ADFG follows.
    Comment: ADFG concluded that reclassifying Snake River fall chinook 
salmon from threatened to endangered is not warranted because the 
species has increased in abundance since the time the species was 
listed as threatened.
    Response: NMFS agrees that since the time of this proposal, Snake 
River spring/summer and fall chinook salmon have increased in 
abundance. Below we present a brief summary of recent returns of Snake 
River spring/summer and fall chinook salmon. Table 1 summarizes this 
abundance data:

       Table 1.--Summary of Snake River Spring/Summer and Fall Chinook Adult Returns at Lower Granite Dam       
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                                                                   Spring/summer                                
                                                   Spring/summer      chinook      Fall chinook    Fall chinook 
                      Year                         chinook total    naturally-      total adult     naturally-  
                                                   adult returns     spawning         returns        spawning   
                                                                    escapement                      escapement  
----------------------------------------------------------------------------------------------------------------
1994P...........................................           3,915           1,721             774             406
1995............................................           1,799           1,116           1,042             350
1996............................................           6,823           3,487           1,270             639
1997............................................          45,082         E 6,500         E 2,100           E 726
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P = Proposed rule published on December 28, 1994.                                                               
E = Estimated return (Personal Communication, Robert Bayley, NMFS 1997; TAC 1997b).                             

Spring/Summer Chinook Salmon Abundance

    In 1994 when NMFS proposed reclassifying Snake River spring/summer 
chinook salmon as endangered, total adult returns (hatchery-origin and 
naturally-spawning) of this species to Lower Granite Dam were 3,915 
(FPC 1995). (Dam counts at Lower Granite Dam are typically used as an 
indicator for Snake River salmon escapement since this is the uppermost 
fish counting ladder in the Snake River.) In 1995, subsequent to the 
proposed listing, total adult returns to Lower Granite Dam were 1,799 
(FPC 1996). In 1996, total adult returns to Lower Granite Dam increased 
to 6,823 (FPC 1997), about 1.7 times greater than 1994 returns. More 
recently, total returns of spring/summer chinook have increased 
substantially. In 1997, a total of 45,082 spring/summer chinook adults 
have returned to Lower Granite Dam (U.S. Army Core Of Engineers (COE), 
1997), about 11 times greater than 1994 returns.
    In 1994, at the time of the proposed reclassification, 1,721 
naturally spawning spring/summer chinook salmon escaped past Lower 
Granite Dam, while in 1995, escapement decreased to 1,116 naturally 
spawning adults past Lower Granite Dam (Technical Advisory Committee 
(TAC) 1997a). In 1996, escapement increased to 3,487 (TAC, 1997a), 
about 2 times greater than 1994 escapement. Estimates indicate that 
about 6,500 naturally spawning spring/summer chinook will escape past 
Lower Granite Dam in 1997 (Personal Communication, Robert Bayley, NMFS 
1997; TAC 1997b).

Fall Chinook Salmon Abundance

    In 1994 when NMFS proposed reclassifying Snake River chinook salmon 
as endangered, total adult returns of fall chinook (hatchery-origin and 
naturally spawning) to Lower Granite Dam numbered 774 (FPC, 1995). 
Adult returns to Lower Granite Dam in 1995 numbered 1,042 (FPC, 1996), 
about 1.3 times greater than 1994 returns. This increasing trend 
continued in 1996, with a total adult return of 1,270 at Lower Granite 
Dam (FPC, 1997)--about 1.6 times greater than 1994 returns. Estimates 
indicate that about 2,100 fall chinook will return to Lower Granite Dam 
in 1997 (Personal Communication, Robert Bayley, NMFS, 1997; TAC 1997b).
    In 1994, at the time of the proposed reclassification, 406 
naturally spawning, fall chinook salmon escaped past Lower Granite Dam 
(TAC, 1997c). In 1995, escapement decreased to 350 naturally-spawning 
fall chinook past Lower Granite Dam (TAC, 1997c). In 1996, 639 
naturally spawning chinook salmon escaped past Lower Granite Dam (TAC, 
1997c). Estimates indicate that in 1997, about 726 naturally-spawning 
fall chinook salmon will escape past Lower Granite Dam (Personal 
Communication, Robert Bayley, NMFS, 1997; TAC, 1997b).
    Comment: In addition to comments regarding recent escapement, ADFG 
concluded that the risk for Snake River fall chinook salmon extinction 
(as measured by stochastic forecasts based on observed escapement) has 
declined since the initial listing of this species. The ADFG also 
commented on the difficulty of reproducing results of a ``likelihood-
of-extinction'' model cited in the Snake River fall chinook salmon 
status review (Waples et al., 1991).
    Response: NMFS agrees that extinction risk for Snake River fall 
chinook salmon has decreased since 1994 due to conservation efforts and 
based on recent increased run sizes.
    NMFS acknowledges that, due to a slight data error, the Dennis et 
al. model results reported in the NMFS' status review are difficult to 
reproduce. However, independent analyses provide estimates very similar 
to those cited in NMFS' status review (Cramer and Neeley, 1993).
    Comment: ADFG concluded that forecasts for future adult fall 
chinook salmon run size cited in the reclassification proposal have 
significantly underestimated the actual escapements past Lower Granite 
Dam. Further, ADFG stated that these projections have so underestimated 
actual escapements that the use of these data is inconsistent with the 
ESA requirement to use the best available scientific and commercial 
data when a listing decision is made.

[[Page 1810]]

    Response: Contrary to ADFG's comments, NMFS believes that projected 
natural-origin escapements have not significantly underestimated actual 
escapements. Based on run reconstruction data developed by the Columbia 
River Technical Advisory Committee established under U.S. v. Oregon, 
the 1994 Snake River fall chinook salmon run size at Lower Granite Dam 
was estimated to range from 269 to 488 adults (CRTS, 1994). Actual 
escapement past Lower Granite Dam in 1994 was estimated to be 406 
adults (Washington Department of Fish and Wildlife (WDFW) and Oregon 
Department of Fish and Wildlife (ODFW), 1995). NMFS agrees, however, 
that it would be unwise to base a species status reclassification, such 
as this rulemaking, solely on the results of predictive models which 
are sensitive to unforeseeable environmental conditions.
    Comment: ADFG derived estimates of the number of spawners needed to 
produce maximum sustainable yield (MSY) and maximum return ranging from 
440 and 570 adult spawners above Lower Granite Dam, and estimated that 
escapements on the order of 1,000 adults would produce strong returns.
    Response: While the estimates presented by ADFG appear reasonable 
given the data that were used, NMFS questions ADFG's treatment of the 
data in deriving these estimates. In addition, ADFG did not present any 
confidence intervals for its estimates of MSY. NMFS' previous 
experience with similar analyses suggests that such confidence 
intervals would be quite large; hence, conclusions regarding this 
analysis must be viewed as highly uncertain.
    Comment: ADFG raised several concerns regarding stray hatchery fish 
and the genetic integrity of the Snake River fall chinook salmon ESU. 
The ADFG stated that, based on dilution models, the gene pool of the 
progeny of wild fish is likely different today than it was a few years 
ago.
    Response: NMFS has not attempted to verify the results presented by 
ADFG for its dilution model, but agrees that unidirectional gene flow 
(from non-ESU stocks into the listed ESU) results in a dilution of the 
native gene pool. The potential and, given the evidence of past 
straying into the Snake River, likely adverse impacts of this 
cumulative dilution underscores NMFS' concern for the genetic integrity 
of the Snake River spring/summer and fall chinook salmon ESUs.
Summary of Factors Affecting the Species
    Section 4(a)(1) of the ESA specifies five factors to be evaluated 
during a status review of a species or population proposed for listing 
or reclassification. A discussion of these factors with respect to 
Snake River spring/summer chinook salmon and Snake River fall chinook 
salmon follows.
A. The Present or Threatened Destruction, Modification, or Curtailment 
of Its Habitat or Range
    In the December 1994 proposed rule to reclassify Snake River 
spring/summer and fall chinook, NMFS stated that hydropower 
development, water withdrawal and storage, irrigation diversions, and 
other land management activities had degraded Snake River salmon 
habitat. NMFS further stated in the proposed rule that changes in the 
operation of lower Snake and Columbia River Dams and changes in land 
and water management activities would likely result in long-term 
improvements in survival of adult and juvenile chinook salmon, but that 
such improvements had not yet been realized.
    NMFS now concludes that migration conditions in the Columbia and 
Snake Rivers have improved since the time of listing due to increased 
spill and natural flow, as well as physical modifications to mainstem 
dams. For example, seven of eight Columbia and Snake River mainstem 
dams now have bypass systems through which outmigrating juvenile Snake 
River chinook salmon can pass more safely. Also, through the 
implementation of the proposed Snake River Salmon Recovery Plan, 
additional spill and flow augmentation have occurred during the 
juvenile outmigration.
    Since the listing of Snake River chinook salmon, NMFS has 
undertaken numerous consultations on activities in the region. Examples 
of such activities include timber and grazing permits issued by the 
U.S. Forest Service and Bureau of Land Management, dredge and fill 
activities authorized by COE, and licensing of hydroelectric projects 
by the Federal Energy Regulatory Commission. Benefits of these actions 
include the following: Between 1991 and 1995, there has been a net loss 
of 622 miles of roads (sources of sediment) in nine Idaho National 
Forests; all irrigation diversions in critical habitat located in the 
state of Washington have been screened; and NMFS has successfully 
settled one of the largest Comprehensive Environmental Response, 
Compensation, and Liability Act (CERCLA) claims in the history of the 
statute (Blackbird Mine), which will eventually result in reopening 
over 100 miles of spawning habitat historically used by chinook salmon 
in Idaho.
B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes
    At the time of the proposed reclassification, NMFS stated that 
several measures had been taken between 1991 and 1993 to reduce 
incidental harvest rates on Snake River fall chinook salmon to 
approximately 50 percent. However, continued and projected low returns 
indicated that these efforts had not reversed the decline of the 
species.
    Since the proposed rule, returns of Snake River chinook have 
increased. This indicates that impacts from commercial and recreational 
fisheries have decreased. Commercial and recreational fisheries in the 
Columbia River basin remain restricted to low levels relative to 
previous years. For example, the Southeast Alaska troll fishery for 
fall chinook salmon was substantially curtailed in both 1995 and 1996. 
Current restrictions in this fishery have resulted in a catch of about 
80,000 fewer chinook than early 1990 quotas. Furthermore, Canada has 
taken steps to substantially reduce its fisheries off the west coast of 
Vancouver Island and in other areas. Also, through the Columbia River 
Fisheries Management Planning process, harvest on spring/summer and 
fall chinook salmon has been set with specific constraints based on 
Snake River salmon run size. As an example, recent agreements regarding 
fall chinook salmon harvest in Columbia River fisheries will ensure 
under most circumstances that harvest rates achieve a 30-percent 
reduction relative to the 1988-93 average Snake River fall chinook 
harvest rate.
    As stated in the proposed reclassification, there are a number of 
scientific research programs which involve handling, tagging, and 
moving fish in the Columbia and Snake Rivers. However, NMFS believes 
that the contribution of these programs to the decline of listed Snake 
River chinook salmon is negligible.
C. Disease or Predation
    Chinook salmon are exposed to numerous bacterial, protozoan, viral, 
and parasitic organisms; however, these organisms' impacts on Snake 
River chinook salmon are largely unknown.
    Predator populations, particularly northern squawfish 
(Ptychocheilus oregonensis), have increased due to hydroelectric 
development that created

[[Page 1811]]

impoundments providing ideal predator foraging areas. Turbulent 
conditions in dam turbines, bypasses, and spillways have increased 
predator success by stunning or disorienting passing juvenile salmon 
migrants. Increased efforts to reduce populations of northern squawfish 
should result in survival improvements of listed salmon, but the 
benefits are not yet fully known.
    Marine mammal numbers, especially harbor seals (Phoca vitulina) and 
California sea lions (Zalophus californianus), are increasing on the 
West Coast, and increases in predation by pinnipeds have been noted in 
some Northwest salmonid fisheries. Since the time of this proposed 
reclassification, NMFS has published a report describing the impacts of 
California sea lions and Pacific harbor seals upon salmonids and on the 
coastal ecosystems of Washington, Oregon, and California (NMFS, 1997d). 
This report concludes that in certain cases where pinniped populations 
co-occur with depressed salmonid populations, salmon populations may 
experience severe impacts due to predation. An example of such a 
situation is Ballard Locks, Washington, where sea lions are known to 
consume significant numbers of adult winter steelhead. This study 
further concludes that data regarding pinniped predation is quite 
limited, and that substantial additional research is needed to fully 
address this issue. Existing information on the seriously depressed 
status of many salmonid stocks is sufficient to warrant actions to 
remove pinnipeds in areas of co-occurrence where pinnipeds prey on 
depressed salmonid populations (NMFS 1997).
D. The Inadequacy of Existing Regulatory Mechanisms
    In the proposed reclassification, NMFS stated that improvements in 
existing regulatory mechanisms had been made since the original listing 
of Snake River chinook. However, due to projected declines in abundance 
during the 1991 through 1993 period, NMFS believed that regulatory 
mechanisms which were in place were inadequate.
    NMFS now concludes that since the time of listing, existing 
regulatory mechanisms have improved. For example, regulations aimed at 
improving river flow and juvenile acclimation for upper Columbia River 
fall chinook salmon are believed to have reduced straying impacts on 
listed fall chinook populations. Commercial and recreational harvest 
regulations have been implemented which appear to be minimizing the 
impacts of these actions on Snake River chinook. A single scientific 
advisory body (Independent Scientific Group) has been established to 
address Columbia River Basin scientific issues. A result of this 
board's formation should be to streamline the management and decision-
making process with respect to Snake River salmon issues. Furthermore, 
implementation of the proposed Snake River Salmon Recovery Plan has 
begun; finalization of this document in 1997 will provide a clear 
direction for the region in achieving recovery of its Pacific salmon 
stocks.
E. Other Natural or Manmade Factors Affecting Its Continued Existence
    Drought conditions have contributed to the decline of Snake River 
chinook salmon; however, these conditions have subsided in recent 
years. In the Northwest, annual mean streamflows for the 1977 water 
year (October to September) were the lowest recorded for many streams 
since the late nineteenth century (Columbia River Water Management 
Group (CRWMG), 1978). Precipitation levels in the Snake River Basin 
above Ice Harbor Dam also were below the 25-year average (1961-1985) in 
the 1979, 1981, 1985, 1987, 1988, and 1990 water years. The 1990 water 
year became a fourth consecutive year of drought condition (CRWMG, 
1991). Drought conditions persisted in the Columbia River basin during 
the period of 1990 to 1994. However, changes in weather patterns in 
1995, 1996, and 1997 have resulted in above average rainfall for Snake 
and Columbia River basins.
    Long-term trends in marine productivity associated with atmospheric 
conditions in the North Pacific Ocean may have a major influence on 
salmon production. Unusually warm ocean surface temperatures and 
associated changes in coastal currents and upwelling, known as El Nino 
conditions, result in ecosystem alterations such as reductions in 
primary and secondary productivity and changes in prey and predator 
species distributions. The degree to which adverse ocean conditions can 
influence Snake River chinook salmon production is not known; however, 
juvenile salmon adapting to the nearshore ocean environment are 
probably particularly vulnerable.
    Artificial propagation has, in some cases, impacted listed Snake 
River spring/summer chinook salmon. Potential problems associated with 
hatchery programs include genetic impacts on indigenous wild 
populations from stock transfers, reduced natural production due to 
collection of wild adults for hatchery brood stocks, competition with 
wild salmon, predation of wild salmon by hatchery salmon, and disease 
transmission.
    Changes have been made in many chinook salmon hatchery programs 
which should decrease the impacts associated with artificial 
propagation. For example, measures have been taken to reduce straying 
of Umatilla River fall chinook hatchery stock into the Snake River. 
These measures include increasing river flows, marking all hatchery-
raised fish, and acclimating stocks in the Umatilla River prior to 
their release. NMFS continues to monitor, evaluate, and refine changes 
that have been made to chinook salmon hatchery programs. This process 
should help ensure that hatchery programs do not impede recovery of 
these stocks.

Finding and Withdrawal

    At the time the reclassification proposal was made, Snake River 
spring/summer chinook salmon and Snake River fall chinook salmon 
appeared to be near critically low abundance levels. However, since 
that time, the abundance of both stocks has increased. These increases, 
combined with the effects of improved management, indicate that the 
risks facing these species are now lower than they were at the time of 
the reclassification proposal. Based on this information, NMFS 
concludes that reclassification of Snake River spring/summer and fall 
chinook salmon from threatened to endangered is not warranted at this 
time. Therefore, NMFS withdraws the proposed rule to reclassify Snake 
River spring/summer and fall chinook salmon as endangered under the 
ESA. NMFS will continue to closely monitor the status of these species 
as well as evaluate the effectiveness of existing and future protective 
and conservation measures to determine whether a change in the status 
of either species is warranted in the future.

References

    A complete list of all references cited is available upon request 
(see ADDRESSES).

    Authority: 16 U.S.C. 1531 et seq.

    Dated: January 5, 1998.
Rolland A. Schmitten,
Assistant Administrator for Fisheries, National Marine Fisheries 
Service.
[FR Doc. 98-622 Filed 1-9-98; 8:45 am]
BILLING CODE 3510-22-P