1976/77 migration of humpback whales into Hawaiian waters composite description

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INFORMATION CENTER

Report No. MMC-77/19
Property of C,;C Library

THE 1976/77 MIGRATION OF HUMPBACK WHALES
INTO HAWAIIAN WATERS: COMPOSITE DESCRIPTION

It
Louis M. Herman, Paul H. Forestell,
and Ronald C. Antinoja
University of Hawaii U.S. DEPARTMENT OF COMMERCE NOA;
Honolulu, Hawaii 96814 COASTAL SERVICES CENTER
2234 SOUTH HOBSON AVENUE
CHARLESTON, SC 294O05--2 13
Submitted December 1979

~~~~~~2 ~Published April 1980
42
Final Report to U.S. Marine Mammal Commission
in Fulfillment of Contract MM7AC014
,_

� 1~Z~ C0L'L[' TION
(.)
Availability Unlimited

4-
Cv

Prepared for

U.S. Marine Mammal Commission
1625 I Street, N.W.
Washington, D.C. 20006

REPRODUCED BY
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~Jf~~~~~ (>no~~~ $SPRINGFIELD, VA. 22161

REPORT DOCUMENTATI ON PAGE
l, Report No. 2. ]. Recipient's Accession No.
E�1C-77/19 PB80-162332

4. Toi:e jod SubtitLe 5. Report Dace

The 1976/77 Migration of Humpback Whales into April 1980
6.
Hawaiian Waters: Composite Description

7. AuthOr(s) 8. Performing Organizacion Report No.

Louis M. Herman, Paul H. Forestell, Ronald C. Antinoja

9. ?erforming Organization Nlame and Address 10. project/Task/Work Unit No.
University of Hawaii
Kewalo Basin Marine Mammal Laboratory (H.I.M.B.) l. Concrac or GranC NO.
1129 Ala Moana MM7ACO14
Honolulu, Hawaii 96814 3u. Type of Report
L2. Sponsoring Organization Name and Address
Marine Mammal Commission
1625 Eye St. NW Final Report
Washington, D,C. 20006
14.
15. Supplementary Notoes
SlemearyNotes The views and opinions expressed in this report do not necessarily
reflect those of the Marine Mammal Commission, its staff, or its Committee
of Scientific Advisors on Marine Mammals.
16. AbsCract
The 1976/77 assembly of'humpback whales in Hawaiian waters was studied through
aircraft surveys, an all-island observer network, sightings from hydrofoil craft, a CB
ship reporting network, military air sightings, and a field station. Fifteen days
were selected from 7 January through 20 April 1977 to sample population parameters and
seasonal trends. The data from these sources and across days indicated Ca) the number
of sightings increased rapidly to a peak near the third week of February, with an
almost equally rapid decline in number of sightings thereafter; (b) the peak calf
population also appeared to be reached in February; (c) subregions of relatively high-
est calf density, identified by aircraft surveys, generally were those where most
total whales were observed; Cd) fewer whales were seen in areas near dense human habit-
ation or disturbance than in more isolated regions; (e) there was a tendency for the
"geographic center" of the population to shift in a northwesterly direction towards
Oahu as the season progressed into late March and April; (f) new mother-calf dyads
appeared to remain isolated from other whales for an initial period, possibly as a
social imprinting mechanism, and then were :typically "escorted" by one or more other
whales without calves; (a) calves were seen, on the average, in pods of increasingly
larger size as the season progressed, so that pod size might serve as a crude index
of the age of the calf; and Ch) a number of defensive responses of the whales to
marine and air traffic were identified The potential for negative impact on the
whales from the ever-increasing marine traffic or whale-watching activities was
stressed.

17. Originacor's Key Worda 18. Availability Statement
Humpback whale; Megaptera novaeangliae;
Hawaiian Islands; migration; population; Availability Unlimited
distribution; conservation; harassment,

L9. U. S. Security Classit. of the Report 20. U. S. Security Classif. of This ?age 21. do. of Pages 22. ?rice

Unclassified Unclassified

This Form may be reproduced. i

Preface

The studies reported in the main body of this paper were carried out
under contract 03-7-208-35088 with the Marine Mammal Division, National Marine
Fisheries Service, N.O.A.A., Seattle, Washington, and were assisted by
financial support from the Marine Mammal Commission. The survey of marine and
air traffic reported in the Appendix was supported by the Marine Mammal
Commission, and the 1978 studies of whale spatial and temporal distribution by
Grant BNS 77-16882 from the National Science Foundation to L. M. Herman. This
report revises and extends some of the material presented in the October 1977
contracted report to the National Marine Fisheries Service. Revisions were
made possible through continued support by the National Science Foundation for
our studies of the Hawaiian humpback whale. The present report is Contribution
No. 579 from the Hawaii Institute of Marine Biology, University of Hawaii.

We are appreciative of support given by the American Cetacean Society,
Maui Chapter. We also thank the U.S. Coast Guard District Office in Honolulu
for assistance to our observers during Coast Guard Flights through the
Northwest Hawaiian Islands; Capt. Bryson and crew of the N.O.A.A. vessel
Townsend Cromwell for their assistance and courtesy to whale observers
accompanying their resource surveys of the Northwest Chain; Herbert
Bonaventure of the Barking Sands Pacific Missile Range Facility on Kauai for
developing and maintaining a whale sighting network among PMRF personnel;
Major Goldstein of the Kaena Point Satellite Tracking Station on Oahu for
allowing our observers access to this important sighting area; Duane Black of
the Lanai Co. for permission to erect our Lanai field station; Paul and Pat
Bernick, who ably helped in many aspects of development of the field station;
and Howard Brancel who made significant contributions to the data collection
phase of the field station.

We also thank Steve Rose and Mary Soares for their help in data
processing through to completion; John Reinke, who provided most of the
initial computer programs; Larry Kelley of Sea Flite, who arranged for the
whale sighting reports from hydrofoil vessels; and Jim Luckey of the Lahaina
Restoration Foundation who developed the CB whale sighting network and
provided its data to us.

There were many who volunteered their services each week as shore
obervers. The data they provided were invaluable. We thank them and the
dedicated island co-ordinators: Paul Bernick, Pete Conally, Amy Fujimoto, Pete
Hendricks, Michael Holt, Arn Nurock, Coreen Sakamoto and Craig Wolf. The
collaboration of Edward Shallenberger in setting up and administering the
observer network was important to its success.

TABLE OF CONTENTS

Abstract.................. 1

Scope of Report .............................2

Materials and Methods ..........................2
Aircraft Surveys........................... 4
Observer Network........................... 4
Field Station.............................9
Hydrofoil Observations ........................9
CB Ship Network............................11
PMRF Observations...........................11
Oahu Migration Survey.........................13
Survey of Northwest Hawaiian Islands .................13

Results and Discussion..........................13
Seasonal Trends in Relative Numbers..................14
Relative Usage of Subregions by Whales and Calves...........21
Seasonal Trends in Usage of Regions..................26
Migration...............................29
Calves and Calf Pods .........................30
Interactions of Whales with Boating Traffic..............38

Summary .................................41

Appendix: Potential Impact of Marine and Air Traffic on Hawaiian
Humpback Whales ............................ 43
Maritime Traffic ...........................43
Aircraft Traffic ...........................47
Publicity Given Whales ........................49
Spatial Distribution of Whales.....................49
Temporal Distribution of Whales....................52
Summary and Conclusions........................52

References................................55

LIST OF FIGURES

1. The main Hawaiian Islands. The inset expands the four-island
region, an area of heavy usage by the whales ............3

2. Routes taken by aircraft during surveys of the islands. Indepen-
dent aircraft surveyed (a) Oahu and the Niihau-Kauai area,
(b) Penguin Bank and the four-island region, (c) Hawaii and
(d) the outlying northerly "migration"f area............ 5

3. The form provided volunteer observers in the all-island observer
network (shore net). One form was completed for each sighting
of a new whale or group of whales................. 7

4. Routes taken by Sea Flite during their interisland transits are
shown by the heavy lines. Circles on land indicate locations
of shore posts for the observer network. Open circles indicate
those stations that contributed data on any of the 15 selected
"maximum data days.1........................ 8

5. The form provided to vessels participating in the CB whale
spotting network run by the Lahaina Restoration Foundation .....12

6. The percentage of total whales sighted by a source of data on
each max data day. Additionally shown are the percentage of
total whales sighted during selected Sundays of the season by
the network of shore observers ...................17

7. The total number of whales and calves seen in each indicated
subregion of Kauai and Niihau over all chartered aircraft'
surveys. The total of whales and calves is shown by the un-
circled numbers. The subtotal of calves is shown by the
circled numbers...........................22

8. The total number of whales and calves seen in each indicated
subregion of Oahu, Penguin Bank, and the four-island area over
all chartered aircraft surveys. The total of whales and calves
is shown by the uncircled numbers. The subtotal of calves is
shown by the circled numbers ....................23

9. The total number of whales and calves seen in each indicated
subregion of Hawaii over all chartered aircraft surveys. The
total of whales and calves is shown bythe uncircled numbers.
The subtotal of calves is shown by the circled numbers .......24

10. The mean pod size (number of whales) for pods with calf and
without during the maximum data days within each month .......34

11. The mean number of calves seen per maximum data day within each
of the four months, based on all sources of data ..........35

12. The percentage of total whales sighted which were calves, during
the maximum data days of each month ...............................36

13. The percentage of pods sighted that had a calf, during the
maximum data days of each month .................................... 37

A-1. Location of airports, harbors, anchorages and roadsteads within
four-island habitat region ........................................46

A-2. Relative density of all whales (1977-1978) .........................50

A-3. Relative density of calves (1977-1978) .............................51

A-4. Relative abundance of whales, all islands of Hawaii combined,
from January through April, during 1977 and 1978. The number
of whales counted in each survey date is expressed as a
percentage of the total whales counted over all surveys in
a season ..........................................................53

LIST OF TABLES

1. Summary of Aircraft Survey Dates and Regions Surveyed .............. 6

2. Interisland Schedule of Sea Flite Hydrofoils .......................10

3. Number of Sightings, Number of Whales (Including Calves), and
Number of Calves for Each of the Maximum Data Dates of the
Season ............................................................15

4. Number of Sightings of Each Pod Size, as a Function of Observa-
tion Method (Source) ..............................................16

5. Summary of Sightings by Shore Network on Indicated Sundays .........18

6. Sighting Ratings Based on Weather and Sea State for Maximum
Data Days and Additional Shorenet Sighting Days ...................20

7. Total Numbers of Whales Sighted in Each Region By Date for All
Data Sources Combined .............................................27

8. Percentage of Total Whales Counted that Were at Kauai and Oahu
During Months of the 1977 Season: All Data Sources Combined ......31

9. Frequency of Occurrence of Different Size Pods With Calf on
Each Max Data Day .................................................32

10. Number and Percentage of Total Calves Sighted Seasonally in
Each Indicated Area ...............................................39

A-1. Types of Vessels in Major Harbors or Anchorages of the Four-
Island Region on February 1, 1979 .................................45

A-2. Sightseeing Tours Advertising Whale-watching ....................... 48

-1-

ABSTRACT

The 1976/77 assembly of humpback whales in Hawaiian waters was studied
during the major period of its residency in Island waters. Data were compiled
from nine aircraft surveys, an all-island observer network, daily hydrofoil
transits between Oahu and Maui, a CB ship network in Maui waters; military
aircraft sightings from the Barking Sands, Kauai station; and a field camp for
whale observations on the northeast shore of Lanai Island. From the mass of
data, 15 days were selected from 7 January through 20 April, 1977 to describe
population characteristics and represent seasonal trends. Over these 15 days,
there were a total of 928 sightings of single whales or groups of whales from
all data sources (many of them were overlapping sightings), for a total of
1,999 whales, including 93 calves. The major findings were (-j) the number of
sightings increased rapidly to a peak near the third week of February, with an
almost equally rapid decline in number of sightings thereafter; (b) the peak
calf population also appeared to be reached in February; (c) subregions of
relatively highest calf density, identified by aircraft surveys, generally
were those where most total whales were observed; (_d) fewer whales were seen
in areas near dense human habitation or disturbance than more isolated
regions; (&) there was a tendency for the "geographic center" of the
population to shift in a northwesterly direction towards Oahu as the season
progressed into late March and April; (Cr) new mother-calf dyads appeared to
remain isolated from other whales for an initial period, possibly as a social
imprinting mechanism, and then were typically "escorted" by one or more other
whales without calves; (.-) calves were seen, on the average, in pods of
increasingly larger size as the season progressed, so that pod size might
serve as a crude index of the age of the calf; and (h) a number of defensive
responses of the whales to marine and air traffic were identified. The
potential for negative impact on the whales from the ever-increasing marine
traffic or whale-watching activities was stressed, and some recommendations for
nethods to protect the Hawaiian population were given.

-2-

Scope of R-iport

Study of the Hawaiian population of humpback whales, Megaotera
nve.arg2.ia., was carried out during their 1976/77 migration into Hawaiian
waters. The study continued earlier work on the 1975/76 migration (Herman,
1977; Herman & Antinoja, 1977). The current studies were broader in scope and
effort than previously, and were carried out over the major portion of
residency of the whales in Hawaiian waters. The principal goals included an
assessment of the distribution and relative abundance of whales seasonally;
investigation of possible migratory routes and of local movements;
identification of important regions for mating and calf-rearing; study of
mother-calf pairs; and the evaluation of actual and potential sources of
harassment or disturbance to the whales.

Not all of these goals were realized fully, but some data were obtained
on each. The overall amount of data obtained was considerable. Sources of data
included (a) aircraft surveys over regions of aggregation of the whales
throughout the main Hawaiian Islands; (b) sightings from a network of shore
observers on each island; (c) reports from a field station on the northeast
coast of Lanai Island established for study of the whales; (_d) sightings from
Sea Flite hydrofoils transiting island waters; (4) reports from a CB-radio
ship network developed by the Lahaina Restoration Foundation; and (f) sightings
by aircraft and ship personnel of the Barking Sands Pacific Missile
Range Facility on Kauai, during their operations off-shore of Kauai and
Niihau. Additional information was obtained from a shipboard survey of North
Oahu conducted toward the end of the season, and from U.S. Coast Guard flights
and N.O.A.A. ship transits we accompanied through portions of the Northwest
Hawaiian Islands.

Material and Methods

Some data were available for almost every day of the period of residency
of the whales in Hawaiian waters, from early November 1976 through to late May
1977. For the bulk of this report, a subset of 15 days from early January
through to end of April was selected for intensive analysis. The trends across
the 15 days were considered representative of seasonal parameters for the
population. Multiple criteria were used in selection of the 15 days, with a
major consideration being a substantial amount of data for that date. If there
were aircraft surveys on a given day, that date was selected unless the
sighting conditions were poor. This criterion accounted for selection of nine
days: 7 and 19 January; 2 and 18 February; 10, 23 and 30 March; and 6 and 20
April, 1977. On most of these days there were significant contributions to the
aircraft data from other sources. The remaining six days were chosen to fill
the intervals between 7 January and 20 April and were 14 and 30 January; 1 and
26 February; and 1 and 16 March. To choose these six days the number of
sightings for each day of the week separating flights was examined and the day
of the week yielding the largest number of cumulative sightings from all
remaining sources was selected. The set of 15 days was then referred to as
"maximum (max) data days." In addition to the "max" data days, data from the
shore observer network on selected Sundays of the season from January 16th
through April 24th were included in some analyses, where noted.

Figure 1 shows the main Hawaiian Islands with area and place names
important to this study identified. The 100-fathom contour, within which

160, W 159, 15811 57' 156, W 155,
T1- I I I

MuuLo~ Pt -HAWAIIAN ISLANDS
Muu
22 - NIIIAU '22'" ' IAUAI-

\7�~~~~~~~~~~~~~~~~~~~Ki~. Pa.~

KAULA I,

I~o~r~ollu~MOLOKAI P

C.OP I t.ka..P~a
MOLOKAI

,~--------AOL PNfk
/~~lat~h~ -'11 P

F~~~ig .TeianHwi a Isands. ThPne xadtefu-aadrgoan are Kofo~ h e a v y -' us age
by-the w hale s
MOLOKAI MU
Loot. Pal.
Ponguin~ run:3y--- -

21' NOplI -t KAIOOLAWE p"upl P.
'r- ---' I --il
Aolaaaapola
I~1ha~r Kaauaai P - 20*
-. LANAI a

a~ ~ P iK�.aa,oi. Pg kIilo

-I~~~~ o
.__L_ ~~~~~~~~~~~~~~~~~~u~. La.. Pa
157' 156 __
156' W 155'

Fig. i. The main ilowailan Islands. The inset expands the four-bsland region, an area of heavy usage
by the whiales.

-4-

almost all whales are found, is indicated. The inset expands the four-island
region of Molokai, Lanai, Kahoolawe, and Maui, which contains a shallow water
area of' high whale density. Other reports (Herman, 1980; Herman & Antinoja,
1977) have described some of the ecological characteristics of the Hawaiian
marine habitat.

Figure 2 shows the paths of aircraft during the aerial surveys conducted
throughout the 1977 season. The flights were principally within regions of
100-fathom water around or between islands. Exceptions were the northerly off-
shore runs between Oahu and east Maui, which were attempts to intercept
migrating whales. Table I lists dates of' aircraft flights and regions
surveyed.

Aircraft were single engine Cessna 172's, Grumman Commanders, or Piper
Cherokees, chartered on an hourly basis. On board were the pilot, a photog-
rapher, and two observers. The flight log and all observations were recorded
on audio tape in real time. We flew at 700 to 800 feet while searching for
whales, and descended to 500 feet for closer inspection of a sighting. When
possible, sightings were orbited for several minutes to fix the location of
the group and determine their heading and to obtain detailed information on
pod composition and behavioral and morphological characteristics of
individual s.

The most complete data, from all dimensions of interest, was that from
aircraft. Position data could be estimated accurately by reference to Vortac
Omni stations located on the various islands, or to visual landmarks; the
number of whales in a group could be determined reliably; and finally,
behaviors and physical characteristics of the whales were readily observable.
Disadvantages of the aircraft platform were its short observation time over
each pod orbited, its relatively low sampling ratio of the population, and its
dependence on good weather conditions.

The observer network was developed in early January, 1977. Between
January 6th and 14th, "Whale Watchers' Workshops" were held on Oahu, Hawaii,
Kauai, Lanai, Maui, and Molokai. Volunteers attending each workshop were given
a 3 to 4 hour lecture and slide presentation on the Hawaiian humpback whales,
including what was known of their history, distribution, abundance, appear-
ance, and behavioral characteristics. The type of information to be collected
by the volunteers was discussed and reporting forms (Figure 3) were distrib-
uted and explained. A local co-ordinator was selected for each island to
assist in the distribution and receipt of completed forms and to enlist new
volunteers. Observers were asked to be at designated shore stations each
Wednesday and/or Sunday of the week, either from 0800 It-o 1200 hours, or from
1200 to 1600. Co-ordinators returned all completed forms to the University of
Hawaii for processing.

Figure 4 shows the location of the shore stations used by the volunteer
observers throughout the season. Not all stations operated on a regular basis,
and a few were staffed only on rare occasions. Open circles identify locations
from which data were obtained during the max data days studied. Closed circles

160' W 559' 158' 157' 156' W 155'
I I I 5

K AU Al
22, - NIIIAtJ - 22'
r ;-����������~~~~~~.... ....

OAIU

MOLOKASi

21- -21

iI'JAI MAjUI

KA1iOOLAWE`-.
HAWAIIAN ISLANDS

20'- 1976/77 WHALE SURVEY
-- REGAR rAARCRAfi ROUItS
OCCASIO94AE AMICRAII ROUILS
- MIGRA1ION AIRCRAf I ROUILfS HAWAII
--W-0 fAIIIOM COF1IOUR

59'- -19'

_I
560' W 1 59' 158' i57' 156, W 155'

Fig. 2. Routes taken by aircraft during surveys of the Islands. Independent aircraft surveyed (a) Oahu and
the Niihau-Kauai area, (b) Penguin Bank and the four-island region, (c) Hawaii and (d) the outlying northerly
"Imigration" area.

-6-

Table I

Summary of Aircraft Survey Dates and Regions Surveyed

Oahu-Kauai- gonolulu-Maui- Hawaii: Migration:
Date Niihau-Oahu Honolulu Hilh toa Hilo 'N. Oahu-N. -Maui
counter�clockwise

January 7'(Fri) X

19 (Wed) xd--

February 2 ("ed) X X X I

18 (Fri) x x I

March 10 (Thu) x x x

23 (Wed) x X XI

30 (Wed) I

6 (Wed) I I

20 (Wed) I

a Actually flown on March 13th but.-data included' ~tlh March; 10'th.

Actually flown on March 1lch but data included with March 10th.

C Actually flown on March 22nd but data included with March 23rd.

Includes brief survey of Upolu Point region of Hawafii

Lrtxr o area coordinator at co 1-125 A-La moan, K.ewala Bain�:, 1ICnalulu, 968124

S ~~~~~a~~~~I~~Oo bserver D a r e ____
sterling t1=12aon statdioni________ 7inish tize _______ Sheet so. __o __

Spot 1,1. ___No. 04 wha~les __-__ CAf Presentl Sbace of padtskaz an on c
Conpass or cloc~k headi~; to whales ______ iscanct to share (miles)
xcvemmenc dircc:�on of0 '4halas

Keajar acxiviry-: -as ing _~n__ svriclg slowl~y ____ io~ing d~
le~tailed beh&viars (see 'say) :inverted breech ___tail wsave ___ head sapa
pectur". (fin) -4ave ___1'cba�in (tail sltap) ___ soundi~ng (-Iukes up)

inverted SW-L~ins ___ rllizg side co aide - bobbing - ubbing other w.halee __
other (de.'cri~be)

Behavioral. narrative: In your o,.n 'Warti, describe .he behaviors of, the aninals, ',owj
I on-, theyi -..re occurr~ng, and cze sequence 11 '.hlchi they ocurrad.. :denzify beizaviors
wl-cb indtivdual an.-L-als, If possible. tf caLf- ?rasenr, descr:Lbe Izs behaviors.
Use back of sheeac I. (and Z U4 necessary).

Dliving char-cartaisicqcs.
Dlvo ~o. Dive TI-ne (-in.) Dive Noa. ie -s - Dive Tim.Dv e (:Hit)

I 7 _ _ . 9 _ _ _ _

7?hysi~cal descripcicr. of whales.
Larze (Mo.) - ~ taidi= (no.) _____
W fin shapes (Sketch dShrac ave-a seen)

C,31oracion of cop side of' pectaral.fias (,indiate no. ouf zni:-aLa in each catev-)
-ttensive whiza ____ aderace w~hiza sligh.: white all black
Undetrmirnned_____

Dolphins nearby? (descrtbe)

Flocoks of Dietz near boihl'S
Boars or ships nearby? (lead' 'ar a-,ay and do .,Jey aproz--f iiaies lj

Seoeing condi.'onn.
Spo�ct% a!.ds (blnoculzrs, etc.) dore)_______
~cnrher: ci'cnr y *- c la%,i y ____ In_
5ea. ,Z sn-eLi wjnve, Billy scmz Gt..ca~n e~ eas

Fig. 3. ThPo rv'-4-dad Volurzeer. cbser-vers in tne a2.-�s rd osre
-eV-;Ozk (Shcre set). Oze ~r a cnee c ahsgrc fan~li
or 3rOuo'. or01: is

Reproduced from
be -aenlable copy.

_ i6GW 159, 158 157, 1566 W 155,

- 1

~~~~~~~~~~IMLKAIA

2i, - 2

HAWAIIAN ISLANDS

20' 1976177 WHALE SURVEY
o SHOJRE SWIAINS REPORFING ON MAXIMUM DAIA J)AVS20

*OMERt SkiORf SIA110OIJS
- 5A1&0It ROUIES HW
100 fAlIMOM C01410UR

1~~~~~~~~~~~~~~~~~~~~~~~~~~~~~-9 -
I ~ ~ ~ ~ I cf i

1601W 1 59, 158, 157' 156, W 155,

Fig. 4. Routes taken by Seaflite during their interisland transits are shown by the heavy lines. Circles
on land indicate locations of shore posts for the observer network. Open circles indicate those stations that
contributed data on any of the 15 selected "mnaximunm data days."

show other stations. The shore net data varied in quality, reflecting the
differing levels of skill of observers. In some cases, reports included
drawings of pod configurations, sketches of the paths of the whales, and
detailed text on behaviors. Some obervers who were on station regularly were
able to synthesize their observations into valuable conclusions about movement
trends and other characteristics of the whales. In other cases, the report was
limited to the number of whales seen and their location. Not all observers
attended the initial training sessions, and it is likely that some of the
reporting differences reflected differences in training. Time and budgetary
constraints did not permit the full co-ordination and follow-up necessary to
assure appropriate skill levels in all observers, and maintain the network
fully. Nevertheless, many of the observers turned out regularly each Wednesday
and Sunday, so that a good number of the stations were operational each
week. Much useful data was obtained. The potential of a good shore network is
sizeable, and with full implementation it can be a highly reliable, valuable
adjunct to the study of the whales. Other than aircraft, the shore network is
the only source for all-island data.

Field Stto

A field station was developed at Halepalaca Landing, on the northeast
coast of Lanai (Fig.1). This site is close to regions of especially high whale
density in Kalohi and Auau Channels. Observers were camped at the station,
which is accessible only by jeep trail from Lanai City, from early February
through to the middle of April 1977. Whales passing nearby could be studied
from shore, using variable-power telescopes and binoculars, or directly from
the sea through the launching of inflatable rubber craft. The main function of
the station was to carry out detailed, protracted observations of the whales
in order to document behaviors and movements, to identify and describe
individuals, and to obtain detailed data on calves. Shore observations from
the field station were restricted by the limited elevation (approximately ~4m),
though good lateral viewing was available. Whales observed were usually easily
reached by surface vessel, however, providing for important supplementary
observations on pod composition and behaviors. Though well situated for whales
observations, the camp was difficult to supply logistically, and was
susceptible to washouts from heavy rains in the Lanai mountains. Its potential
could increase considerably with better logistical support.

Hydrofoil Observations

During 1977, Sea Flite hydrofoils made multiple daily transits between
Honolulu and Maalaea Bay, Maui, and between Honolulu and Nawiliwili, Kauai.
They also made less than daily trips between Maalaea Bay and Kailua-Kona on
the Big Island as well as occasional trips to Kaunakakai, Molokai on the way
between Oahu and Maui. Table 2 presents Sea Flite schedules, and Figure 4
shows the routes followed by the craft. The greatest number of transits was
between Honolulu and Maalaea Bay. The path around the south side of Lanai was
used from approximately 15 December 1976 through to 15 April 1977. According
to Larry Kelley, operations manager of Sea Flite, approximately six trips were
made through Kalohi Channel to Kaunakakai during this period.

The Sea Flite data were highly reliable within the limits of the areas
covered and the restrictions placed on sighting probability and viewing
duration because of the high speed of the craft (approximately SO km/hr).

-10-

Table 2

Thterisland Schedule of Sea Flite Eydrofoils

1. Honolulu to Maalaea, Maui

LV HNL ARR MAUI LV MAUI ARR HNL FREQME1CY
0730 1010 1020 1245 Daily
0800 1030 1055 1320 Daily
1340 1630 1640 1900 Daily

2. Maui to Hawaii (Kailua-Kona on W. Hawaii)

LV MAUI ARR EAW LV EAW ARR MAUI FREQUENCY-
1115 1330-. 1410 1610 3-4 times per week

3. Honolulu to Kauai (Nawiliwili)

LV HNL A.RR KAUAL LV KAUAI ARR FM FREQUENCY
1310 1550 1610 1850 Daily
0715 0955 1015 1255 Twice/week

4. Honolulu to Molokai and Maul
Any trip in Block 1 above could stop at Molokai on request. One example:

LV MAUI ARR .1fi LV MLK ARR FML FnqTENCcy
1020 1125 1140 1310 On occasion

-11-

Since the craft followed the same path regularly, its data contributed
importantly to detection of seasonal trends in abundance and distribution. Sea
Flite captains were well coached in whale spotting, and completed sighting
forms while enroute. The reports, however, were restricted to the time and
location of the sighting, an estimate of the number of whales present, and
only brief reports of behaviors. Negative reports were also filed.

CB Shi Notwor

The Citizen Band (CB) ship network was directed by James Luckey of the
Lahaina Restoration Foundation. Data collected were made available to us.
Skippers of vessels berthed in Lahaina were recruited as volunteer whale
spotters and reported on sightings whenever they happened to be cruising in
the waters of the four-island region. The vessel skipper was provided with a
sighting form (Fig. 5) showing the four-island region and a grid overlaying
the waters between the islands. On sighting whales, the skipper communicated
the position of the whales via CB radio to the Lahaina Restoration Founda-
tion's shore station at dockside in Lahaina. Positions of the whales were
given in reference to the grid network. The number of whales present was
estimated and brief statements of behaviors were sometimes provided.

Data from the CB network were voluminous, as there were commonly many
ships in the Auau Channel and east Kalohi Channel regions each day. The
network provided daily coverage of the important four-island region and its
data describe seasonal trends in that area well. However, it is often not
possible to determine the degree of overlap among reports from adjacent boats
on the same day, and the number of whales reported in a sighting may have
questionable reliability, or be only broad estimates attempting to bracket the
true number. The potential of the network is considerable, and with more
instruction to the skippers and more extensive reporting procedures, its value
can increase. The operation, within the limits of its scope, was well
executed.

PMRF Observations

The Barking Sands Pacific Missile Range Facility (PMRF) is located at
Mana Point on Kauai (Fig. 1). The facility includes an underwater listening
range extending northwesterly from Mana Point. Naval exercises are conducted
periodically in the area between Mane. Point and north Niihau and in the
regions extending north and northwesterly from that area. The exercises
include low-level aircraft flights and deployment of surface vessels.
Personnel on these flights and ships reported the presence of whales to PMRF
headquarters under a program of assistance to our project set up and
co-ordinated by Mr. Herbert Bonaventure of PMPF. PM'RF also assisted throughout
the season in obtaining recordings of whales from their listening station.

Substantial data were received from PMRF and it is our best resource on
the presence of whales in the Kauai-Niihau area. The data were largely
restricted to locations of whales, numbers seen, and on some occasions, brief
statements of behavior. The position data are generally highly accurate, as
sophisticated navigation aids were available to the observers. Relatively
little is contributed by PMBF to the data reported in this paper, because
their observation dates tended not to coincide with dates chosen for analysis
in this study. Problems with PMRF data are similar to those encountered by our

/ "i.._..., ,..,
4J0L On __ ~-.-a

II i I a � " I I
~---'---r-----b4 ......�- t ........---'--'-' 8 ......,Q` ......--I1---,~`--

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iaa i I I Ia I I I I '

- - -.---a------- ~-L-)--- Ad- 14~e-- A - S u---,- -,-.
& I I I I I IIII

to.~~1 �I ospl A aaiaa4St.I I
,a ....tao.. i4 - ''/
A S......1 S -.~ - - - o0 -~0....-$....I-....l-.....g. . . . ---....l.---
Iol I4~ Iru~ lu I I I I
I.�.~ t~~�1. '~� I~~r I J I II ..~~.

UA� - -- -------
PI I aa

- -~~~~~~----t---$ - ;
LAN~~~~~l . ~ ~_ ,U*I.~

at, -- --66--- --.-I � 4 � 4 � 44 ------laS - I
I I llII

1 I i I I I I
I� �
tIUiVI:'AC}< W(ItACl SIGIII'INGS ...." ..... ...... - y- - s - --u- --1-
I a I I a I I I -

DAaaaaa.a ................. ... a...ac I -
kVF A[II[Rn thll CILMMENIS __________ 1.

i. 5 e o prvi I

Resor t i I o I I u o
................... i I' I I 1 . ....
..................... I t I I I I ....
t ~ ~ ~ ~ I I ..'

S~~~~ ' , ------_-gt---l1--~ --{, I
~�~~~ ~ ~oi 1uu1 Sulc)

Fig. 5. The form provided to vessels participating tin the CB whale spotting network run by the Lahaina
Restoration Foundation.

-1 3-

own chartered aircraft, but are compounded by the high speed of PMRF aircraft.
To somne extent, this is counterbalanced by the greater number of flights
taken.

Near season's end, attempts were made to study out-migration around
northwest and north Oahu. Whales appear to aggregate in this area late in the
season. From April 10th through May 18th 1977, observers were stationed on a
near-daily basis at the IKaena Point Satellite Tracking Station. From its
near-shore approximate 225-in elevation, a commanding view of the adjoining
leeward and north coasts of Oahu is obtained. In conjunction with these shore
observations, a ship survey was conducted between Waimea Bay and Honolulu on
29 and 30 April , 1977.

Migration possibilities in the Northwest Hawaiian Islands were also
studied. We placed two whale observers aboard the N.O.A.A. vessel Townsend
Cromwell during its voyage from Midway to Honolulu from 2 to 12 November,
1976, and during its immediately following resources survey of Niihau and
Necker Islands from 16 to 24~ November. Whale observers were also placed aboard
U.S. Coast Guard C130 low-level inspection flights of the Northwest Hawaiian
Islands during transits from Oahu to Midway and Kure Islands and return. One
to two observers accompanied flights on each of the following outbound dates:
November 30th, 1976 and, in 1977, 19 January, 2 and 23 February, 9 and 23
March, and 6 and 20 April. After layover in Midway, aircraft generally
returned the day following the outbound date. The inbound flight was usually
again at low altitude, and a number of the flights stopped briefly at French
Frigate Shoals. In such cases, a somewhat more southerly route was taken than
on the outbound flight.

Results and Discussion

Data records were prepared for each sighting on a maximum data day from
each of the various observational sources. Each data record included the date
and time of the sighting, sighting conditions (weather and sea state), total
number of whales, presence or absence of a calf, the position of the whales in
latitude and longitude and their direction of movement, presence or absence of
boats within a quarter-mile radius and whether any approached the whales, the
major activity of the whales, and a listing of occurrence of various types of
behaviors. The data records were cross-tabulated by computer in a variety of
ways to obtain statistics, and to reveal trends and interactions of variables.
The overall data base consisted of 928 sightings of one or more whales. The
total number of whales sighted over all max data dates was 1,999, including 93
calves. These numbers greatly exceed population estimates (e.g., Herman &
Antinoja, 1977), and hence many of the whales and calves were obviously the
same animals seen more than once over the season, as well as on the same day
by multiple observers. In most cases, only partial data were available from a
sighting, and the various analyses reported herein showing lesser numbers of
sightings or of whales than the base numbers given indicate that data were
missing in some categories.

-14-

Table 3 summarizes the number of sightings, whales, and calves reported
on each max data day by each source of data. The totals for each source
indicate that the relative contributions to number of sightings was greatest
for the CB-net, followed by Sea Flite, aircraft, shorenet, field station, and
Barking Sands. However, these sources varied in the average number of whales
counted or estimated per sighting (Table 4), so that there is some
rearrangement of their relative contribution to total whales sighted. The
aircraft, while orbiting pods, obtained the best viewing angle for counting
whales and is regarded as the best estimator of number of whales per pod for
the overall population. The favorable viewing angle of the aircraft also
allows for the ready detection of calves. Of the total number of whales
sighted by aircraft, 9.2% were calves. The lower calf ratios reported by the
CB-net (2.7%), Sea Flite (1.1%), and the shorenet (4.7%) reflect their less
favorable sighting conditions, or the brevity of their contact with a pod. The
high calf ratio reported by the field station (13.4%) is accounted for by the
concentration of its efforts in a region having many calves, as is discussed
more fully in a following section, and by its protracted detailed observations
of pods. The high ratio from the Barking Sands source (14.3%) was based only
six total sightings and hence cannot be regarded as a reliable estimator of
relative calf abundance.

The trends across the set of maximum data days listed in Table 3 re.-veal
an orderly increase in numbers of sightings and numbers of whales as the
season progressed, through to a peak number of 143 sightings and 297 whales on
February 18th, based on all reporting data sources. Seasonal trends are
somewhat obscured by the differences in numbers of sources reporting on each
max data day, and/or the degree to which a given source was operative on the
date. Variability in the shorenet data, for example, occurred because
observers were at their stations mainly on Wednesdays and Sundays. Four max
data days, February 18 and 26, and March 1 and 10, were neither Wednesdays nor
Sundays (the shorenet began operation only after January 14th).

Seasonal trends are revealed more clearly by Figure 6 in which the number
of whales sighted by aircraft, Sea Flite, and CB network on each max data day
are plotted as the percentage of total whales sighted by that source. For
example, the 20 whales sighted by aircraft on January 7, 1977 are normalized
to 4.9% of the total when divided by the 412 whales sighted by aircraft over
all max data days.

Additionally, Figure 6 provides data from the shorenet source on every
other Sunday of the season from January 16th through to April 24th. Also
included are Sunday, January 23rd, to show the early trends more clearly, and
Sunday, February 20th, to help identify when peak numbers of whales were
present. Table 5 summarizes the data from the shorenet on the indicated
Sundays which form the basis for the shorenet graph in Figure 6.

Figure 6 shows that the peak numbers occurred on February 18th for both
the aircraft and Sea Flite sources of data, and on February 20th for the shore
network. For aircraft and shorenet the peak is very steep and for Sea Flite,
moderately steep. Sea Flite also shows a somewhat lower secondary peak on
January 30th. In some contrast, the data for the CB network, which derived
almost entirely from the four-island region, show more constant numbers during

0 Sonma -0AL 2OTAL T .L OTAL CVES OAV! 5OU7=- - =AL 741TA :CTA. C.ALVES
SPT :1-ALL5 rL7zS SPOS ZaAL= CAL7ES (23

:.~~~~ ~~~ ~~~Z 7 38 2.9 Maz1. L87
(F~t.) Arra:Lf 2.0 . 10.0 C T gin) C3 Id 2. 5
4 2.2 0~~3 0.0I .

3arkjAzxd 2.30.0 t 1. 56 1.22 2. 9.'
(7-1u Alzae Z 3 6 3.2
~~2.4 46 1.00 3~~~~~~~to 3.0 (M 'lee2is 42 4 9.5
(3 M nee 2.3 64 a St.d~ilic�e 1.0 Li 2 1 9.2.
5414-1 -Z 14, 27 . Fals.a 2 7 2.14.3

Y-ar LB6 43 34. i.1.2
58 I 3 2.5 (IT4d) 2�ac 2.5T T 50 0.43
('Vel) �:c ral= 1.s2 2. S..2 Seid.iza i 3.0
20 'fe 20 39 Z . 2. Sharptac 920 0.
Set-i.5:A 2. Z90 0. 0 71a..ai.st 3 5 I- zo.0.
lar~~~=2 I Z 0 0.0
1.5 0 0~~ ~~~~~.0 ~ IAC 2.0 51. .. .
,an i~~~~~~o 3 C3 lee L~~~~~~ 14 33. 35.
(Srn 20 r2aC Z 5 76 Z . I.a 171'.
Sax!" .�a 2.3 56 Z . L.. S'i.dremec I 9 L.2
Th'rimrac 03. 66 2 3.4 rteldsita 1.5 .0.

1.09 U.9 125.0 !Mi2.0 56 1.97 5. 4
(~~~e4) ~ ~ Z 39 1-5 i 7.3 (4d) .Urcrlif - .2 23.1..
20:9. ' l e t 3 3.23 205L 1.0 0
30a2.15: 1... 1.9 0 00 5&422:4 1.6240 .
memo me ~ a 3 2 3 .3 33 a -10.5
1.3~~~~~~~~~.

r~~~~~midsca 5~~~~~~~~~~~~~~ ~ 1.2. 0 .

Teb~~~~~~~~~~_ 1.2..S

�e~~~d2.�~~~a 2.2. 37 2. 2~~~~~~7.7 2~J)~00.0

(S&: 75 1.0 43 3.0i 202.72.1.
~~~�e~~~~ds~~~~ 1.2 24~~~~~~~~ -Z J9 208L .0 a . 1.2
6 ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~hr. 1. 'S. 03 0.027
Ftaldata j Af 2~~~~~~~~~~~~. 1 -.sa 2.4 3!00.
7e~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~Sa o 1.3 1.3-7714;
(~~J ~ ~~ ~~6 1.24 9 6.7 Ap~~~~~~~~~ 20 2.2 5' 9.3~~~~~.
20 :T~~~~~c 30 80 3 2.6 (SJ~~~~~~~~~~d3 .~~~~:crkand 1. 3 14

Sea~~~~~~~~~~~~~2..2.:t ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ eroue from 0000 0ln 2 .
3 ~ ~ ~ ~~~~~~~~~~ ~ b s a vial c o py 200I-00

Table 4

Number of Sightinge of Each Pod Size, am a Function of Observation Method (Source)

�SOURCE POD SIZE
Total Total Avg. No.
1 2 3 4 5 6 7 8 10 12 14 Spota tfhalea per Pod

Aircraft N 75 63 43 12 6 0 0 1 0 0 0 200 416 2.07
% 37.5 31.5 21.5 6.0 3.0 .0.0 0.0 0.5 0.0 0.0 0.0

CB Net N 73 120 59 31 9 8 - 3 2 0 2 1 308 782 2.54
% 23.7 39.0 19.2 10.1 2.9 2.6 1.0 0.6 0.0 0.6 0.3

Seaflite N 114 74 18 4 5 0 0 0 0 0 0 215 357 1.66
% 53.0 34"4 8.4 1.9 2.3 0.0 0.0 0.0 0.0 0.0 0.0

Shorenet N 50 65 30 10 5 1 0. 0 1 0 0 162 351 2.17
% 30.9 40.1 18.5 6.2 3.1 0.6 0.0 0.0 0.6 0.0 0.0

Fieldata N 17 6 5 3 2 2 0 0 0 0 O 35 78 2.23
% 48.6 17.1 14.3 8.6 5.7 5.7 0.0 0.0 0.0 0.0 0.0

Barkaand N 1 2 3 0 0 0 0 0 0 0 0 6 14 2.33
% 16.7 33.3 50.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

TOTAL N 330 330 158 60. 27 11 3 3 1 2 1 926 1998 2.15
% 35.6 35.6 17.1 6.5 2.9 1.2 0.3 0.3 0.1 0.2 0.1

40---

LU
a~~~~~~~
t--

5 30-- /
AIRCHAFI A.----.
o' '. SEAFUFE 0 Ci
LU / ., NEWA ----
Q ~~~~~~~// * '1C3E1OK-
~~~~~~~~~~ . , '
/ /
/

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.4 ~~~~~~~~/

I- /

In;A,
o // \/

I~~~~~~~~~~~~--'" / '/I'.

ci�
O~~~~~~~. -. Y-i~~~
/' o. .."

Z / / V-~.':__..___, _ .-',
0u I~c- / ;----+.4. -H--,

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: I� o ' /%

o/~ ~ ~~~~~~~~~~~1] "�~ �' ...... . . . . '.....-

0~~~I I I ...... It-?---1---- -- I--I-It--- --I I I I I -
JAN IAN JAN IAN FEB FEB fEB fEB MAR MAR MAR MAR APR APR APR APR
9 16 23 30 6 13 20 27 6 13 20 27 3 10 17 24

SIGHTING DATES

Fig. 6. The percentage of total whales sighted by a source of data on each muax data day. Additionally
shown are the percentage of total whales sighted during selected Sundays of the season by the network of
shore observers.

Table 5

Summary of Sightings by Shore Network on Indicated Sundays

Date Sightings Whales Calves

Jan 16 9 20 1

23 12 41 1

30 31 66 2

Feb 13 55 123 4

20 75 148 4

27 23 48 1

Miar 13 15 24 1

27 15 34 L

Anr 10 8 12 1

24 5 8 1

Totals 248 524 17

the entire month of February, with the relative maximum occurring on February
2nd. They also show a relative rise on January 14th. From these data, it
appears as if whales may appear in sizeable number relatively early in the
four-island region and somewhat later in regions to the northwest. The mig-
ration section of this report will discuss seasonal distribution trends more
fully.

The aircraft and shorenet data, which cover the entire island chain, are
remarkably similar in trends and are thus mutually supportive of each other.
In Figure 6, both aircraft and shorenet data show a steep decline in relative
numbers after the peak date. For the shorenet, the decline occurs within a
period of one week. Because of bad weather, aircraft flights were postponed
until March 10th following the peak period of February 18th, but probably
would have revealed earlier declines if surveys had been made. This contention
is supported not only by the shorenet data, but by the Sea Flite sightings
which decreased steeply from February 18th to the 26th. The suddeness of the
decline, as well as the suddeness of the earlier appearance of a large number
of whales, is somewhat surprising, in view of the protracted period over which
at least some whales are present from early November until early June, and in
view of descriptions of migrations of Southern Hemisphere humpback whales in
which the migration flow appears gradual (Dawbin, 1966). It would be important
to determine whether these trends persist over successive seasons.

The data of Figure 6 are influenced by the prevailing sighting
conditions. Table 6 summarizes the mean ratings of the sighting conditions on
each max data day, as supplied by aircraft and shorenet reports, the only
sources regularly providing weather data. Ratings of sighting conditions on
the additional shorenet days plotted in Figure 6 are also given. To obtain a
sighting rating, the weather and sea-state conditions reported by the
observers were combined to yield four qualitative ratings: excellnt =
weather clear to cloudy-bright, seas calm to slight; good = weather as in
excellent, but seas moderate with minor whitecapping; medocr weather
clear to occasional light rain, seas moderate to rough with whitecaps in
abundance; ooor = weather clear to cloudy-dull, with very rough seas, high
waves, whitecaps and spray. Both mediocre and poor imply windy conditions with
moderate to heavy spray obscuring visibility. In general, sea state was
considered a more crucial determinant of sighting condition than weather,
unless lighting was poor or visibility obscured by haze, rain squalls, or the
like.

Table 6 shows that mean sighting conditions over both aircraft and
shorenet sources of data remained between excellent and good through to
February 20th, with the exception of January 16th. Hence the data on the
sudden appearance of large numbers of whales is not biased with respect to
sighting conditions.

From February 26th to April 10th, with the exception of March 10th, the
mean sighting ratings moved closer to or even beyond the mediocre category.
Thus, a portion of the sudden decline noted in Figure 6 may reflect the poorer
sighting conditions present after February 20th. That the majority of the
decline is probably real, however, is indicated by several independent sets of
data: (a) the cumulative March 10th data, obtained under near-excellent
sighting conditions, which evidence the steep decline; (b) the February 27th
shorenet data, obtained with sighting conditions not severely reduced, but

-20-

Table 6

Sighting Ratings Based on Weather and Sea S'rate

for Maximum Data Days and Additional Shorenet Sighting Days

Mean Sighting Conditiona

Date Aircraft Shorenet Bothb

Jan 7 1.11 ---1.11T
16 --- 2.50 2.50
19 1.00 1.75 1.16
23 -- 1.84 1.84
30 --- 1.71 1.71

Feb 2 1.67 1.41 1.56
13 - 1.40 1.40
18 1.00 1. 00 1.00
20 --- 2.00 2.00
26 -- 3.00 3.00
27 -- 2.61 2.61

Mar I
10 1.00 2.00 1.09
13 - 3.10 3.10
16 -- 3.11 3.11
23 3.07 3.50 3.17
27 ---- 2.27 2.27
30 2.17 2.37 2.29

Apr 6 2.50 3.00 2.60
10 - 3.00 3.00
20 1.00 2.00 1.31
24 ---- 1.00 1.00

aSighting code: i= Excellent; 2= Good; 3= Mediocre; 4= Poor

bweigh-aed .ean

-21-

which nevertheless show the decline; and (c) by our daily field station
observations (not reported in Figure 6) between late February and early March,
which showed the decline even though there were a few good sighting days
intervening in that period.

The conclusion seems forced that significant numbers of whales departed
from the main observational areas in Hawaii during the last week of February
or slightly later. It seems likely that the departure was part of an out-
migration. Some of the departing whales appear to have relocated to the Kauai
and Oahu areas temporarily Prom areas further east, as will be discussed in
more detail in the migration section, while others may have left directly for
northern waters.

Figures 7, 8 and 9 show the total numbers of whales (adults plus calves)
and calves sighted by aircraft over all surveys, on max data days, within each
of the indicated subregions of the various islands. Subregions (dotted lines)
are areas of relatively constant orientation paralleling straight runs of
coastline, or in the case of large open areas such as Penguin Bank, convenient
partitions of the space into subspaces. Reiog~ns (solid lines), discussed in a
following section, consist of two or more subregions, though in a few cases
they are the same as a subregion. The subregions reveal the detail of usage
and are also important for interpreting movement directions, the subject of
a later report. Regions are more functional for interpreting seasonal trends.
Being generally larger areas than subregions, they encompass more sightings
and provide a more reliable data base. The different subregions are not
equivalent in area, nor are the different regions. Relative usage must be
interpreted within that context.

The aircraft data in Figures 7, 8and 9 were considered the most
representative, among the various data sources, of the relative usage of
subregions. Unlike other data sources, the aircraft devoted approximately
equal observational effort to almost all of the subregions within a survey
area.

The Maui complex was surveyed more often than were the Oahu-K'auai-Niihau
areas, which in turn were surveyed more frequently than was the island of
Hawaii (Table 1). Unfortunately, one cannot simply divide the counted whales
in each figure by the total number of surveys comprising that figure to obtain
comparisons of mean usage, because the number of whales seen in part depended
upon the survey date. Within each figure, however the relative usage numbers
are unbiased, or nearly so.

Kauai-Niihau-D.a~u. The Kauai-N'iihau data (Fig. 7) reveal relatively
heaviest usage in the southeast portion of Niihau, where 18 whales and I calf
were sighted. By these data, use of this subregion exceeds that of a number of
the coastal subregions of the west Maui area (Fig. 8), which are commonly
considered important whale habitats. Niihau, with a total of 30 whales,
including 2 calves, seems to be a preferred habitat to Kauai, 'with a total of
ten whales sighted. Although some animals were seen in the 15-UM wide
Kaulakahi Channel between Niihau and Kauai, during our surveys, and by Barking
Sands personnel during their flights, there does not seem to be a continuity
in the distribution of the population from one island to the other. On our

30' -

22' - NIIH-AU j- K, KAUAI

KAULA -

iI I I I
1614 W 30' 1604 30' 159

Fig. 7. The total number of whales and calves seen in each indicated subregion of Kaual and Niihau over
all chartered aircraft surveys. The total of whales and calves is shown by the uncircled numbers. The subtotal
of calves is shown by the circled numbers.

220 '

30'
K AHOOLIAWiE

1586, W 30 i 17. 3Os 156"

Fig. S. The total number of whales and calves seen in each indicated subregion of Oahu, Penguin Bank,
and the four-island area over all chartered aircraft surveys. The total of whales and calves Is shown by the
uncircled numbers. The subtotal of calves Is shown by the circled numbers.

20' -

30' 156 W 30' 155 3'

Fig. 9. The total number of whales and calves seen in each indicated subregion of llawaii over all chartered
aircraft surveys The total of whales and calves Is shown by the uncircled nuinbera. The subtotal of calves is
shown by the circled numbers.a,

-25-

survey flights, whales were not seen along the coasts of Kauai closest to
Niihau. Barking Sands personnel have encountered whales there on occasion, as
have some shore observers, but the major concentration on Kauai seems to be on
the coast furthest from Niihau.

Two calves were seen on Niihau and none on Kauai. The calf seen on the
northwest shore lay next to its mother in the still waters of the bay, and
seemed to be nursing. It appeared to be quite small.

Figure 8 reveals the relatively low usage of Oahu as compared with the
four-island region. The Oahu data should be compared with the data of Figure 7
because they were largely collected on the same flights that surveyed Niihau
and Kauai. On that basis, Oahu usage is considerably less than Niihau but
barely less than Kauai. Oahu becomes more important late in the season as a
temporary habitat, as does Kauai (see next section). The relatively most
important subregion on Oahu is the north sector, with six whales, including
one calf, sighted.

Four- f.gjin. The remainder of Figure 8 shows the heavy usage of
portions of the four-island region, including Penguin Bank. There seems to be
little regular movement between Penguin Bank and Oahu, judging by the
relatively few whales sighted in Kaiwi (Molokai) Channel. The southwest and
northern 'subregions of Penguin Bank with 28 and 33 whales, respectively, had
the relatively greatest usage. Calves were sighted more commonly in the
southern half of the Bank (7 calves) than in the northern portion (2 calves).

Many whales (31) were seen along the southwest coast of Molokai and
relatively few (9) along the southeast coast,' although there were more calves
(3) seen in the latter subregion than in the former (2). Possibly, whales of
the southwest coast are continuous with the Penguin Bank population. One of
our regular shore observers, Joan Aidem, stationed on the southwest coast of
Molokai at Kolo Wharf, reported on February 27 her impression from cumulative
sightings, that a mass of whales sweeps west down the coast of Molokai early
in the morning and returns in the opposite direction in the afternoon, passing
Kolo Wharf generally between 1530 to 1800 hours. She noted that on windy,
rough days the whales seemed to head eastward much earlier. This description
sounds very much like a daily movement between Penguin Bank and the south
coast of Molokai.

In the remainder of the four-island region between Molokai, Lanai, Maui,
and Kahoolawe, there was a band of most intense relative usage encompassing
the subregion on the northeast coast of Lanai (27 whales), the mid-Auau
Channel subregion (26 whales), and the Kihei coast of Maui from McGregor Point
to Cape Kinau (27 whales). The collective count for the three near-shore
regions bordering the coast of west Maui from NIapili to McGregor Point was 23
whales. This is surprisingly light considering that shore observers and the CB
net regularly report large numbers of whales in these subregions. It may be
that the numerous reports principally reflect the large observer effort put
into these coastal areas. The bulk of the whales in reality seem to be in
subregions further seaward or along less populated coasts.

There is a widespread distribution of calves throughout the various
subregions of Figure S. The northeast coast of Lanai (3 calves), the Kihei
region of Maui (4 calves), and the southwest coast of Molokai (3 calves), and

-26-

the two southerly subregions of Penguin Bank contained the relatively greatest
numbers of calves. The presence of many calves along the Lanai northeast coast
is confirmed by close-hand observations from the field station. The Kalohi
Channel nearshore areas, especially the northeast coast of Lanai, the Kihei
region of Maui, and the south coasts of Molokai appear to be the most
important calf-rearing areas in the four-island complex. Penguin Bank, outside
of the four-island area is also important.

fawa i. Finally, Figure 9, for Hawaii, shows highest usage in the
subregions surrounding and near Upolu Point. Twenty whales, including three
calves, were sighted in the subregion adjoining the north coast of Upolu
Point, 17 along its west coast, and 11 further south to Keahole Point.
Subregions of lesser importance, but still significant usage, occur at the
southeast portion of the island. We again find calves most common where whales
are most common.

U P rn. From Figures 7 to 9, a striking usage pattern emerges,
of importance in assessing habitat preferences of whales. By and large, whales
tend to be found in relatively greatest numbers in subregions that are most
remote from areas of dense human population or human use. Thus, Niihau is
preferred to Kauai. Oahu is little used, with the exception of the rural
coastline of the north shore. The south coast, encompassing the Honolulu and
Pearl Harbor areas, is little used. Penguin Bank has many whales, as does the
remote southwest coast of Molokai. Fewer whales are seen near Kaunakakai. The
uninhabited northeast coast of Lanai is highly preferred as is mid-Auau
Channel and the rural area of the Kihei coast. Along the heavily populated
southeast coast of west Maui, there is relatively lesser usage. On Hawaii, the
areas along Upolu Point are nearly uninhabited by humans, while the lesser
used central western coast (Kona coast) is heavily populated. This is not to
say that human population is the only factor determining habitat preference.
Deep water areas, such as Pailolo channel between Molokai and Maui, are little
used except probably for ingress or egress. Also, there are some subregions
with little human habitation that are little used by the whales, e.g., west
Lanai. The windward areas of some of the islands are not used much, but this
may reflect the limited extent of shallow water available. The high usage of
the northeast coast of Hawaii shows that prevailing wind conditions may not be
a major factor in determining usage. Also, Penguin Bank is regularly exposed
to strong, gusty trades, but is highly preferred. North Kahoolawe is little
used and has no human habitation, but is regularly bombed by low-flying
military aircraft. The simplest generalization is that the whales tend to
avoid areas of dense human habitation or use, selecting instead from among the
remaining subregions of lesser habitation. In such selection, multiple
criteria are undoubtedly used.

Seasonal Trends in Us o f Re

Table 7 summarizes seasonal trends on relative usage of regions by
whales, based on all sources of data. For some regions, observations were not
made on all max data dates. Nevertheless, marked differences in usage of
different regions are apparent and some interesting seasonal trends occur. The
underlining in Table 7 indicates the date on which peak usage of a region
occurred. For almost all regions this was sometime in February, consistent
with the overall data on peak periods in Figure 6. Somewhat earlier peak usage
occurred in mid-Auau Channel (January 30th); in the Ka Lae to Cape Kumakahi

-27-

~ab In 7

Total. Thmbar3 off '--hles Sightad im Each R.egica

3y D~ata 4-or AUL Data Sourtes Combi~ed

!ANU ~ ~ ~ _____ KARC A."-M AUL
7 14 19 30 2 23 is 26 1. LO 16 2.3 30 6 20

All Coasts 7 2172

.A=1Coast.s 9 3 is LS 24 14 14 13 31 3 6 1.38

AU2. Coasts 2 a i 7 i 3 3 6 1 3 8 3 69

aHlul.-?anjuim Bank 4 2 4 ' .3 1 4 30

C-'ZM~~~ ~ ~ 19LI a5 1 60 13 2 21 4 .3 5 7 18

4 3 3 2 6 .2 Z 9

LA2{AZ:
3:ae~a-?Ealao& 1 z 3 i s 1
a~laca--Klkoa 3 i 6 8 .2 3 4
Ki.rxa-4i.a-u " I 9 25 20 20 a1 7 2 2 3 9 LI. a 22 3 L 2

?-k==c czx
Ddev 17-atr 7 16 9 6 2. 20 .3 7 1 i.2 72

Nazi` ~-Mc~rmgur 43 7 27 24 72. 52 335 12 31' 4 42- 2 2.0 3 4.34
McGrr~cr-K-L~au 7 a 15 38 3.5 4-8 14 10 25 2.4 5 1 7 2207

~~~~ 3 ~~~~~~~ 4 19 32 "I 25; 28 7 LI 9 3 .3 6 3 2.86

N" ad Cas 2 6 1 9

-Klh~~~~~~ co 1 -w1 3 3

Kea.~~Qla-Ra Lam ~~2 8 3 7 2.21
Ka Lae--c u-mar-ahl10 1 3 2.4
C ~K- ahl-u-oliu 8 2 22 32

: OTALS: 5 8 2.00 " 7 196 215 26 7 294 1_10 78 i:~S 84 2116 .8 30 44 2.932

-28-

region of Hawaii (January 19th), though coverage of this area by observers was
spotty; and in the Pailolo Channel region (January 14th). The data are
suggestive that the earliest arrivals at the island of Hawaii are at its
southeast side, though the regions of most intense seasonal use are on the
northwest and northeast sides. Possibly, these early arrivals have come from a
northeasterly direction, and slightly missing the northeast point, Cape
Kumakahi, strike the coast at southeast Hawaii first.

An interesting early usage of the four-island region is indicated by an
observation of 16 whales in the Pailolo Channel area on January 19th. Addi-
tionally, there was a report on January 18th from the vessel Viva of the
CB-net of 12 to 15 whales near the southeast portion of Pailolo Channel. On
January 17th, there was a report from another vessel of "too many whales to
count" off north Lanai, not far from where the tongue of Pailolo extends into
Kalohi Channel (Fig. 1). On January 14th, a vessel reported a "whole bunch" of
whales near the Seven Sacred Pools area just south of Hana, Maui. These data
hint at an arrival from the north or northeast of Maui with animals proceeding
down the Pailolo Channel to the main Auau and Kalohi Channel assembly areas,
or else proceeding clockwise around east Maui from Hana and entering the
four-island water via the channel between Maui and Kahoolawe. Very early
arrivals appearing in the four-island region seem to be lone animals or, at
times, pairs. The first whale report in the 1976/77 season was from Sea Flite
on November 3, 1976 of an animal 6 nm west of McGregor Point, Maui. The next
sighting by Sea Flite was on November 22 of a whale near Koko Head, Oahu and
then from the 22nd to the 30th of November, a total of 14 whales, all
singletons or groups of two, were seen in the four-island region. There was
also an early report on November 30 from N.O.A.A. research vessel Townsend
Cromwell of three whales on the southwest tip of Penguin Bank. In contrast, at
Kauai, the earliest report, based on hearing of whale songs, was on December
30, 1976.

The data in Table 7 on late usage reveal an extraordinary number of
whales at Kauai on the 30th of March, and also relatively large numbers,
though not a maximum, around Oahu on the 23rd of March. Our observations (not
cited in Table 7) of significant numbers of whales around north Oahu in late
April and May support the Oahu late-season trend in Table 7. A relatively
high proportion of the sightings were of calves. The combined data from Kauai
and Oahu may indicate a massing of animals prior to late out-migration around
these two islands. Paradoxically, though the earliest arrivals seem to
approach from the north or northeast, the latest departures appear to leave
from the northwest sector of the main Hawaiian Island chain.

Over the entire season, the regions of heaviest usage (100 or more
animals) based on all reporting sources were, in order, the Napili to McGregor
coast of Maui (431 whales); the north and northeast coasts of Lanai from Kaena
Point to Kikoa Point (241); the Kihei coast of Maui from McGregor Point to
Kinau (227); Penguin Bank (198); the mid-Auau Channel (186); and all coasts of
Kauai (138). We noted previously that there are biases inherent in the
combined data from all sources, reflecting uneven observer effort across
regions. The unbiased aircraft data give much lesser density estimates for the
Napili to McGregor regions of Maui than do the combined sources, a number of
which were concentrated in that region. Penguin Bank and Niihau would
undoubtedly stand relatively higher than indicated were they sampled by more
data sources. Only the chartered aircraft and the Sea Flite cruises reported

-29-

on Penguin Bank, and the chartered aircraft and Barking Sands flights were the
only sources of data for Niihau.

Migration

Attempts to determine the migratory routes of the whales into and out of
the Hawaiian Islands included surveys of the Northwest Hawaiian Islands by
aircraft and surface vessel, flights along the northern perimeter of the main
islands from Oahu to Maui at distances of from 10 to 15 nm from coastal areas
(Fig. 2), and study of the aggregations appearing late in the season around
the north coast of Oahu.

Notws Hawaiia Isans No whales were seen during any of our
inspections of the Northwest Hawaiian Islands. The earlier inspections, from 2
November, 1976 through to 2 February, 1977, would be expected to have
uncovered in-migrants, if significant numbers were following the chain of
islands southwesterly to the main islands. The later inspections, from 23
February through 20 April 1977, ought to have revealed out-migrants, if
significant numbers were following the chain northwesterly. We did receive
notice of a sighting by Karl Kenyon on French Frigate shoals of a humpback
whale mother and calf sighted on February 17th off-shore of the shoals in
"green water."f The calf was reported to be less than one third the length of
the mother. This sighting, and one or two others at widely separated times by
the surface vessel Eaa .Rid~er, can be considered "stragglers."

We also inquired of residents of Midway Island whether any whales had
been sighted there at any time in the past. With the exception of a mother and
a calf, species undetermined, swimming between Midway Island and Kure Atoll
about six years ago, reports were uniformly negative. Also, NAVFAC personnel
on Midway reported detecting no whale songs on their monitoring gear (which
gives a visual analog of acoustic energy). It seems then that Nishiwaki's
(1972) statement that humpback whales are commonly seen around Midway Island
in winter is mistaken. In sum"ary, the evidence gathered for this report
strongly indicates that the main humpback whale population wintering in
Hawaiian waters does not pass through the Northwest Hawaiian Islands during
migration.

Waer Imedatlyi North DI 2gJ11 2 _!aI~L. Aircraft surveys flown
north of Oahu and Maui (Fig.2) on 2 February and 10 march 1977 also yielded no
sightings. The first flight was approximately two weeks prior to the peak
period of residency of the whales in Hawaiian waters and the second one to two
weeks after the period of rapid decline in population (Fig. 6). One might have
expected the interception of scoie whales if large numbers were migrating
southward or southwesterly toward Maui at the first flight or northwesterly
away from it during the second flight. However, the timing of the flights may
have been sufficiently displaced from the peak migration interval to have made
sighting probabilities low. These probabilities are further reduced by the
wieexpanse of ocean to be covered, the fairly short sampling period of the
aircraft, and the fact that the whales may migrate at any hour including at
night. It is also possible that the aircraft failed to pass over the main
migration routes. The data discussed in the previous section on seasonal
trends indicated some tendency for early arrivals to appear at the northeast
portions of Maui and Hawaii. If so, we would have failed to cross most of that
path, except for the final in-bound leg near Maui.

-30-

Late-Season Agregations. Table 8, derived from the data in Table 7,
shows the percentage of the total sightings for all regions that were at Kauai
and at Oahu during the months of January, February, March, and April of 1977.
For both islands, the percentage tends to rise as the season progresses. The
steepest rise occurred during March and April at Kauai and during April at
Oahu. This may indicate that many whales move towards these two islands late
in the season before departing to their summer feeding areas. This may be
especially true for mothers with calf, which seem to be among the last classes
of whales to out-migrate. Other classes of whales may tend to use other
departure routes. During our nearly daily observations at Kaena Point, on
Oahu's northwest corner, a total of 71 whales were seen between 10 April and 2
June 1977. Of these, 15 were mother-calf pairs, comprising 30 of the 71
sightings. During the cruise of the University of Hawaii vessel .Ni']L on 30
April, 1977 from Waimea Bay on North Oahu to Kaena Point, then to Honolulu, a
total of 27 whales were counted in nine groups. The 27 included four calves.

O. In summary, the composite migration picture suggests that the
earliest arrivals tend to be single animals or pairs. Later arrivals may
appear in relatively large groups. Some of these groups may enter the
four-island region via the Pailolo Channel, perhaps intercepting Maui at
points to the northeast. Other groups seem to arrive early at Hawaii from a
northeast direction. It may be that those whales seen at northeast Maui have
crossed the channel from Hawaii. In any event, from the four-island region
some of the population may disperse westward to Kauai, Niihau, and perhaps
Oahu. The first arrivals in Kauai that we were aware of were more than a month
after the earliest reported arrivals in the four-island region.

The out-migrants in the earliest stages of the return migration e.g., in
early March, may leave directly northward through the Pailolo and Alenuihaha
channels. We have little data to confirm this, however, During the later
portion of the out-migration, many whales seem to move towards Oahu and Kauai,
remain there for a while, and then depart. The direction of the final seaward
move from these areas is still unknown. Neither in-migration nor out-migration
occurs to any significant degree through the Northwest Hawaiian Islands.

and Calf Pods

ompsitifnd a -Siz& of tJe Pod _. ith Caf. There were 93
sightings of calves over the 15 max data days, based on all sources of data
(Table 3). As with our previous observations of the Hawaiian population
(Herman & Antinoja, 1977), pods with more than one calf were never seen,
suggesting that mothers with calf avoid other mother-calf pairs. Herman and
Antinoja reported that the most common calf-pod consisted of the mother, calf,
and a single adult "escort" whale. This arrangement characterized 48% of the
calf-pods reported by them during their Winter/Spring 1976 sightings. During
the Winter/Spring 1977 sightings summarized in this paper, the trio
arrangement characterized 45% of the calf-pod sightings (Table 9), a remark-
ably close correspondence.

For the Winter/Spring '77 sightings, there was an increase in the
percentage of sightings of unescorted mother-calf pairs over that seen during
the Winter/Spring '76 season--29% of all calf-pod sightings were of unescorted
pairs in 1977 as compared with 17% in 1976. However, the 1976 data were based
on sightings from the end of February onward, while the 1977 data included

Table 8

Percentage of Total Whales Counted that Were at Kauai and Oahu During
Months of the 1977 Season: All Data Sources Combined

Island January February March April

Kauai 6.2 6.0 7.4 12.2

Oahu 0.8 3.3 5.1 14.7

-32-

Table 9

Frequency of Occurrence of Different

Size Pods With Calf on Each Max Data Day

Pod Size (incl. calf)
Total
DATE 2 3 4 5 6+ Calves

Jan 7 0 2 0 0 0 2
14 1 2 0 0 0 3
19 0 3 0 0 0 3
30 3 2 0 0 0 5

Feb 2 6 2 3 0 1 12
13 4 6 1 0 0 11
18 5 4 4 2 0 15
26 0 2 0 0 0 2

Mar 1 2 1 0 0 0 3
10 3 5 2 0 1 11
16 0 1 0 0 0 1
23 1 8 0 1 1 11
30 1 3 1 2 0 7

Apr 6 1 1 0 0 0 2
20 0 0 3 2 0

Total 27 42 14 7 3 93

% 29.0 45.2 15.1 7.5 3.2

-33-

observations during January and early February. Table 9 shows that in January
and early February, there was a large percentage of unescorted mother-calf
pairs. Figure 10 reinforces this observation, demonstrating that there is a
sizeable increase in the mean size of the pod with calf (i.e. in the number of
whales accompanying the mother-calf pair) as the season progresses. The mean
size of all-adult pods (pods without calf) did not change correspondingly. The
increase in the size of the calf-pod was therefore not an artifact reflecting
general increases in size of whale groups as the season unfolded.

From the data of Table 9 and Figure 10, a pattern emerges suggesting that
young calves may often be accompanied only by the mother. Herman and Antinoja
(1977) have suggested that an early period of isolation with the mother may
allow for the formation of a strong mutual social attachment. Following the
initial period of isolation, the mother-calf pair may then be joined by an
escort (or escorts) which we hypothesize serve, in part, a protective
function. Whether the mother-calf pair seeks out other whales, or other whales
are attracted to the pair, and join them, is unknown. Perhaps, once the mother
has recovered enough from the parturition experience to travel about, and/or
the calf strengthens sufficiently, the pair simply enters areas of denser
habitation by whales (e.g., see Figures 7, 8 and 9), and a reciprocal
attraction between the pair and other whales occurs.

To some degree, then, the number of whales accompanying the mother-calf
pair may reflect how long the pair has been in contact with other whales. This
raises the interesting possibility of broadly estimating the calf's maturity
according to the size of the pod in which it is found. The larger the size of
the pod, the older the calf may be, at least within the limits of the months
from January through April.

Tempral Distribution -Q Cavs Table 9 shows that calves were seen
from early January through late April, during each of our max data days.
Additionally, calves were seen as late as the end of May during our shore
observations from Kaena Point, Oahu, as was noted earlier. Figure 11
summagrizes the data of Table 9, and shows the mean number of calves sighted
during each max data day within each month of the season. The temporal
distribution of relative calf abundance in Figure 11 is very similar to that
found for all whales, shown earlier in Figure 6. The steep increase in mean
calf sightings in February and the decline thereafter indicate that the peak
calving period was in February, assuming the majority of the calves are indeed
born in Hawaiian waters rather than during the southbound migration. Judging
by the presence of some unescorted mother-calf pairs seen in March and April
(Table 9), it appears that several calves may have been born during those late
months.

Calves, along with their mothers, may remain in Hawaiian waters for
relatively protracted periods. This is demonstrated by Figure 12, showing that
as the season progressed there was an increase in the percentage of total
whales sighted that were calves. Also, Figure 13 shows a nearly linear
seasonal increase in the percentage of total pods sighted that contained a
calf. Taken together with Figure 11, which revealed a seasonal derea~se in
the absolute number of calves sighted, the interpretation of Figures 12 and 13
is that there was a selective, continuing out-migration of classes other than
mother-calf pairs as the season progressed, increasing the relative proportion
of calves and calf-pods. A rough guess from these data is that a mother-calf

3.5 -

2.5 -

PODS WITHOUT CALVE-B
z

JAN FEB MAR APR

MONTH

Fig. 10. The mea pod size (nu.mber of hal as) -for -Jodes Ruth

calf and vithout dur~na the data days v-ithin each, month.

< 1-

LJ.menau-ero 6a---e ee
d 7v hnac 1 on h 0 saucasc-

- 35=

10 --

LU~ 8 --

z
ULU

2 --

JAN FEB MAR APR

MONTH

Zig. 12. The Percentage of total whales s.ghted which

were cal7es, dur4Ig the maximum data days of each month.

-37-

18 --

14--

14 -a.

> 12 ---
LU

V 60 --
>
TO

JAN FEB MAR APR

MONTH

Fig. 13. The percentage of pods sighted that had

a calf, dur-ag the -pz-4-= data da7s of each =onth.

pair may remain in Hawaiian waters for between five to eight weeks before
finally out-migrating. Other classes of whales may remain for shorter periods.

Sipatial Dlistributio.n DI~ CalvgSes nal. Figures 7, 8, and 9 give
the cumulative spatial distribution of calves over all max data days combined.
Many of the subregions favored by mother-calf pairs were those favored by
other whales as well. There were some exceptions, such as the Niihau region
and the southeast coast of Molokai.

The data on seasonal distribution of calves reveal a westerly and
northwesterly shift in concentration of calves as the season progressed,
consistent with the general seasonal shift for all whales noted earlier. In
Table 10, the number and percentage of calves sighted in various large regions
is indicated for the combined January-February period and for the combined
March-April period. In the first time period, 84.9% of the calves sighted were
in the four-island region or in Hawaii., in what may be called the easterly
half of the main island chain. In March and April, this percentage declined to
57.5%, with the largest relative decrease occurring at Hawaii. The largest
relative increase in April was at Oahu, and the largest absolute increase at
Penguin Bank. The westward spatial shift appeared to continue past April 20th,
the last max data day contributing to the data of Table 10. We have previously
mentioned our ship survey of the north and west coasts of Oahu on April 30th,
1977, which yielded a count of four calves, and our continued sightings of
calves near K~aena Point, Oahu, throughout much of May, 1977. The seasonal
shift may be part of a gradual northwesterly out-migration route through the
main islands taken by some mothers, but this requires further study.

Interactions DI Whales A=i Boatin-a Tr~affic

A boat observed within a one-quarter mile radius of a pod was defined as
"in the vicinity" of the whales. Sea Flite and vessels of the CB-net are
surface craft, and sightings reported by either source in actuality may be
instances of a boat in the vicinity of whales. Reports from these sources did
not include the distance of the sighting from the boat, or whether the
observer's vessel approached the pod after the initial sighting, and are
therefore not included in our data on boat-whale interactions. The volumin-
ous data collected from these sources leave little doubt, however, that in in
the four-island region, boats may frequently be within the vicinity of whales
(c.f. Appendix to this report).

During aircraft surveys of the whales, information was collected on boat
activity near whales. The information was also requested from shore observers
(Fig. 3), though individual observers varied greatly in their attention to
this category of information. We therefore limited our data to the aircraft
reports and to the shore forms for which a positive notation on boat activity
was made. Of a total of 62 reports of boats in the vicinity of whales,
subsequent closer approaches by the boats were reported in 14 cases (22.6%).
The 62 pods with boats nearby represent 117 whales, and the 14 pods approached
contained 29 whales, or 24.80% of the total. If we can generalize from this
sample result, it would appear that 20 to 25% of boats in the vicinity of
whales may attempt to approach closer.

Our observations of responses of the whales to aircraft and surface
vessels confirmed earlier descriptions of responses of whales in the 1976

-39-

Table 10

Ntraber and Percentage of Total Calves Sighted
Seasonally in Each Indicated Area.

January- Marc1 -
February April
AREA N Z N Z

Kauai - Niihau 5 9.4 4 10.0

Oahu 1 1.9 5 12.5

Penguin Bank 2 3.8 8 20.0

4 island Region 39 73.6 21 52.5

Hawaii 6 11.3 2 5.0

TOTALS 53 100.0 40 100.0

-.4o0..

assembly (Herman, 1977; Herman & Antinoja, 1977). Though there were many cases
in which whales showed no apparent response to the presence of an aircraft or
surface vessel, in other cases defensive responses such as pod dispersal,
sounding, evasive underwater swimming, and maintaining distance occurred. For
pods with calf, the sheltering of the calf between mother and escorts was seen
again, as was an adult (presumably the mother) moving the calf away from the
source of disturbance.

As in our 1976 observations, the probability of a defensive response
appeared to be inversely related to pod size. Singletons and pairs seemed wary
and difficult to approach by surface vessel. With increased numbers of animals
in the group, there appeared to be fewer defensive responses and in cases of
very large groups, the animals appeared undisturbed by the presence of
aircraft, boat, or diver. On March 25th, 1977, f or example, two of our
observers (P. Forestell and H. Brancel) were able to remain in the vicinity of
a pod of 15 whales for almost three hours while the pod drifted slowly along
next to the observers' rubber inflatable craft. The group included 11 adults,
three subadults (judging by their smaller size), and one calf. The pod was
undisturbed when the observers entered the water to document the pod's
membership and activities on 16-mm film. Whales passed on all sides of the
photographer and one whale, drifting slowly by, carefully raised its pectoral
fin over the head of the diver to avoid brushing him.

Mother-calf pairs unaccompanied by other whales were often difficult to
approach and defensive. For example, the approach of our large 65-ft surface
vessel, .Ncj'i, towards a mother-calf pair swimming off leeward Oahu on 30
April 1977 was met with a series of highly evasive underwater maneuvers
including frequent changes of direction. On another occasion on this same
cruise, a calf was observed lying on its back waving its pectoral fins in the
air. The boat hove to and the calf, on seeing the boat, turned and swam
rapidly to meet it. At that moment, a large whale, presumably the mother,
appeared in front of the calf and quickly turned it away from the boat. The
pair swam off rapidly.

A type of defensive response not identified by us in earlier reports was
"tail swishing." This was a sideways back and forth movement of the tail
flukes in the near-horizontal plane. Generally, the movement occurred just
beneath the surface. It may be a threat display and on one occasion was
encountered by one of us (LMH) during an underwater approach toward a juvenile
and adult. The juvenile lay obliquely at the surface nearly touching the
larger whale. On being approached, it began to swish its tail laterally with
increasing velocity. The diver retreated. Long ago, Scammon (1874) described
'sweeping" as 'the action of a whale when wielding its flukes in an offensive
or defensive manner, causing a great commotion in the water' (p. 312). In
Southern Hemisphere waters humpbacks have been observed using their tails to
beat off attacking killer whales (Chittleborough, 1953).

Surface vessels probably commonly encounter one or more of these various
types of defensive responses when approaching whales. If harassment is defined
as the elicitation of a defensive response by the whale, there may be numbers
of instances of harrassment in Hawaiian waters. How harassment affects the
whales on a long-term basis is not well understood, though a review of the
history of the Hawaiian humpback whale (Herman, 1980), notes that a habitat
shift may occur as a response to chronic or severe disturbance. The data

-41-

presented earlier in this report, showing apparent preferences of whales for
subregions removed from areas of dense human habitation or activity, are
further indicants of the possibilities of local habitat shift by whales in
response to the presence of humans.

Summary

The 1976/77 assembly of humpback whales in Hawaiian waters was studied
during the major period of its residency in Island waters. Observations were
compiled from six data sources, including surveys by chartered aircraft
throughout the eight main Hawaiian Islands, reports from Sea Flite interisland
hydrofoil transits, reports from civilian and commercial surface vessels
contributing sighting information via a CB radio link to a shore station,
observations of a network of volunteer shore observers, reports from Navy
vessels and aircraft operating in the Kauai-Niihau area, and observations from
a field station in daily operation on the island of Lanai. Additional data
were contributed by observers placed aboard U.S. Coast Guard flights through
the Northwest Hawaiian Islands, and aboard N.O.A.A. ship surveys in that
region.

From the mass of data, 15 days were selected from 7 January through 20
April 1977 to represent seasonal trends and the data from those days were
analyzed intensively. Over these 15 days, there were a total of 928 sight-
ings of single whales or groups of whales, for a total of 1,999 whales,
including 93 calves.

The data revealed a steep rise in total whales sighted through to a peak
near the third week of February. A rapid decline in number of whales sighted
occurred thereafter. The peak number of calves also appeared in February.
Study of seasonal changes in distributions suggested that early aggregations
occur in the four-island region between the islands of Lanai, Molokai, Maui
and Kahoolawe. The whales appear to arrive from a northeast or northerly
direction. Early arrivals were also noted in Hawaii, along its southeast
coast. The topography of the coast of Hawaii is such that the approach of
whales might also have been from a north or northeasterly direction. From
these areas in the four-island region and Hawaii, the whales may distribute
themselves westerly and northwesterly in increasing proportions as the season
progresses. Toward the end of the season, significant numbers of whales are
seen at Kauai and along the north shores of Oahu. A number of these sightings
are of mother-calf pairs who may linger in these areas for many days and
finally are not seen again. Oahu and Kauai may serve as temporary staging
areas for the return migration, for those departing late, but are not heavily
used at other times.

Subregions of relatively highest whale usage were identified through
results of the all-island aircraft surveys. The important subregions on Hawaii
are at or near Upolu Point, and through to Keahole Point on Hawaii's west
coast. In the four-island area, a band of subregions stretching -from the
northeast coast of Lanai through mid-Auau Channel to the Kihei coast of east
Maui was the most heavily used. There was also heavy usage of Penguin Bank,
especially its westerly and northerly areas, and the adjoining southwest coast
of Molokai. The southeast coast of Niihau was also an area of relatively heavy
usage.

- 42 -

The subregions in which moat cal ves were found generally corresponded
closely to those where most total whales were -observed. These included the
Upolu Point regions of Hawaii, the Kihei subregion of Maui, the northeast
coast of Lanai, the southeast coast of Molokai, and the southerly half of
Penguin Bank. There were relatively fewer calves seen off Niihau, despite the
high total count of whales.

Examination of regions that were little used by the whales revealed a
tendency by the animals to a-void areas near dense human habitation or
disturbance, in preference to more isolated regions. Populated areas near Maui
show less usage than more rural zones. The same is true for Hawaii, Molokai,
and Oahu. Niihau, heavily used, is almost entirely rural. Kahoolawe, subject
to heavy bombing by military aircraft, is little used, though unpopulated.

As the season progressed, calves were seen, on the average, in pods of
increasingly larger size. It was suggested that newborn calves may remain
isolated with their mothers during the early post-parturition period, perhaps
as a social attachment (imprinting) mechanism, and that associations with
other whales may be delayed until later. As the season progresses, an
increasing percentage of the total sightings are of pods with calf, suggesting
that mother-calf pairs may remain in Hawaiian waters the longest of any class
of whales. The overall birth rate may~be modest. The ratio of calves to total
whales sighted from aircraft averaged less than 10% (Table 3), which compares
closely with data for the Winter/Spring 1976 season reported by Herman and
Antinoja (1977).

Data from aircraft and the oberver shorenet revealed that of 62 groups. of
whales observed with boats within roughly a quarter-mile radius, the whales
were approached even closer by the boats in 1~4 cases (23%). In view of the
attraction of whales for humans, this is not a surprising figure, and is
suggestive of a significant potential for harassment. Some of the
species-typical defensive responses of the whales to surface vessels and
aircraft were noted (cf. Herman & Antinoja, 1977) and their occurrence might
be used as an indicant of whether given actions by humans are disturbing to
the whales.

No evidence was found of any significant migration of humpback whales
through the Northwest Hawaiian Islands. Further efforts at study of out-
migration might more profitably be directed toward late-season surveys by
boats of waters adjoining Oahu and Kauai. Early-season studies of in-migration
should focus on areas north and northeasterly of Maui and Hawaii.

-43-

APPENDIX

POTENTIAL IMPACT OF MARINE AND AIR TRAFFIC ON HAWAIIAN HUMPBACK WHALES

Louis M. Herman and Paul H. Forestell

During 1977, the waters within the four-island region of Maui, Molokai,
Lanai, and Kahoolawe were identified as a major winter assembly area for the
Hawaiian population of humpback whales. During 1978, aerial surveys around all
the islands of Hawaii indicated that the waters within the four-island region
accounted for a full 47% of all whales sighted. The four-island region is also
important as a maritime recreation and tourist area, and is both a fishing
ground and an access route to outlying fishing areas. It additionally serves
as a passageway for marine traffic to and from Oahu. Commuter airlines fly
over the waters regularly, at times at low altitude, during scheduled flights
between the islands of Maui, Lanai, Molokai, and Oahu. The extensive marine
and air traffic within this important whale habitat poses a significant
harassment threat. Though there are other off-shore areas in the Hawaiian
islands where humpback whales may be found in considerable numbers--e.g.,
within Penguin Bank, and to a lesser extent, along the Northwest coast of
Hawaii--it is within the four-island region that the combined usage by whales
and humans is at its maximum.

In order to assess the magnitude of the harassment potential within the
four-island region, the following material was gathered:

a. The number and types of vessels berthed or moored at
harbors or roadsteads on the islands of Maui, Lanai, and
Molokai were counted and cataloged (the island of
Kahoolawe is used exclusively for military operations and
is without commercial or recreational harbors).
b. Those commercial vessels specifically advertising whale
watching cruises were identified.
c. Interisland commercial marine traffic and transient marine
traffic were described.
d. The number of commuter airline flights to Maui, Lanai, and
Molokai were noted for the two principal commuter airlines.
e. Three charter aircraft companies specifically advertising
whale-watching flights were identified.
f. The spatial and temporal distribution of whales in the four-
island region for the winter 1976/77 and 1977/78 seasons
were determined. These data provide the context within
which the harassment potential of marine and air activities
can be evaluated.

Maritime Traffic

The main harbors and anchorages in the four-island region are shown in
Figure A-1. They include Lahaina Harbor and Anchorage (or Roadstead), Maalaea
Bay Small Boat Harbor, Malo Pier, and Kihei Beach, all on Maui; Manele Bay
Small Boat Harbor and Kaumalapau Harbor, both on Lanai; and Kaunakakai Harbor
on Molokai. There are additional bays on the island of Maui at which a few
small boats are moored (e.g., at Kaanapali, just northwest of Lahaina), and
there is a small harbor, Kamalo, near the southeast corner of Molokai which

-44-

serves principally for the launching of small boats from trailers. Facilities
for launching of trailered vessels also exist at all of the harbors in Figure
A-1. The number of trailered vessels launched daily was not formally assessed,
but informal observations from the past four years suggest that such craft may
be as numerous as berthed or moored vessels.

Table A-1 presents the number of vessels berthed or moored at the main
harbors and anchorages of Figure A-1 on January 20, 1979. "Hauled out" indi-
cates that a vessel was in drydock for repair or repainting. All vessels are
classified as either (a) private pleasure craft (used for private fishing or
general recreation); (b) charter fishing, diving, or sight-seeing boats; or
(c) commercial fishing boats. Vessels were further designated as either sail
or power craft. Malo Pier and Kihei Beach are not included in the data of
Table A-i, but there were 15 sailboats moored at Malo Pier and five at Kihei on
January 20th. The Lahaina Roadstead data are accounted for by the moorage
figures presented for Lahaina Harbor. The number of vessels moored at Lahaina
Roadstead would normally be expected to increase markedly by the end of
February, as additional transient craft arrived for the winter tourist season.

It can be seen in Table A-1 that the potential traffic from Maui greatly
exceeds that from either Molokai or Lanai. On Maui, private sailing vessels,
especially those in the mid-range size (25 to 45 feet), constitute the major
source of marine traffic. Power charter vessels, again in the mid-range size,
are an additional major source of traffic.

Not all of the boats counted venture out with equal frequency, and some
may never leave their berths for weeks at a time. Real use is not easily
determined, as owners are not available in many cases, or may be unwilling to
say how often they use their boat. Technically, berths are for the use of
operational craft. Commercial boat charters for fishing, sightseeing, diving,
or interisland recreational excursions constitute a major portion of the
marine traffic in and out of Lahaina Harbor, as these, unlike the private
vessels, may make one or more daily excursions into the adjoining waters.
Thirty-seven brochures advertising commercial charters were collected on Maui,
eight of these specifically advertising whale-watching cruises (see Table A-2).
Seven of the whale-watching boats depart from Lahaina Harbor, while the eighth
departs from an anchorage at Kaanapali.

In addition to the more or less permanent sources of marine traffic
listed in Table A-i, there is additional transient private and commercial
movement between the four-island area and Oahu and Hawaii. Private vessels
from Honolulu, where there are great numbers of boats, may travel interisland
for recreation, and anchor at Maui for varying lengths of time. The same is
true for Big Island (Hawaii) boats, although there are fewer of these. We did
not attempt to estimate the amount of such traffic. Private vessels from the
west coast of the mainland appear in increased numbers at Lahaina during the
winter season. Our informal observations from the 1978 season indicated that
perhaps a dozen or more large sailing vessels from the mainland United States
or Canada were moored at Lahaina Roadstead.

Finally, an interisland tug and barge service, operated by Young Brothers
of Honolulu, runs daily between Honolulu and Molokai/Maui, except on Saturday.
On its eastward travel, the barge may pass through the Kalohi Channel between
Molokai and Lanai, stopping at Kaunakakai, Molokai and then proceeding to

-45-

Table A-1

Types of Vessels in Major Harbors or Anchorages of the Four-Island Region
on February 1, 1979

MAUI LANAI MOLOKAI
Lahaina Hbr Maalaea Bay Manele Bay Kaumalapau H Kauanakakai H
Vessel Type:

Private Sail B M H B M H B M EH B M H B M H
<25' 11 8 - 7 - - 2 - - - - - - - 1
25-45' 30 11 - 10 - 4 5 - - - - - 4 6 -
>45' 11 4 - 1 - - - - - - - - -
Power
<25' 82 - 6 - 3 7 - - - 4 4 18 2
25-45' 3 - - 4 - - - - - - - - 12 2 -
>45' - 2 - - - - - - - - - - - - -

Charter Sail
<25' - - - - - -
25-45' 4 - - 1 - - 4 - - 1 - -
>45' 4 - - - - - - - - - - -
Power
<25? 4 2 - 1- - - -
25-45' 17 - - 13 - 1 - - - -
>45' 12 - - 2 - - - - - - - - - - -

Commercial Fishing
Power (only)
<25' 2 - - 8 - 1 3 - - - 9 2 1 8 -
25-45' 4 - - 9 - 2 1 - - - 2 - - - -
>45' - - - 3- - - - - -

Subtotals: 110 29 0 65 0 11 22 0 0 0 11 6 22 34 3

Island Totals: --------- 215 --------- ------ 39 --------- ----59 ---

Note: B = Berthed; M = Moored; H = Hauled out for maintenance
Charter vessels include sport-fishing, diving, and tourist cruises.

AIRPORTS HARBORS AND ANCHORAGES

Molokai I Kualapuu Molokai I Kaunakakai Harbor
Lanai 2 Lanai City Lanai 2 Kaurnalapau Harbor
Maui 3 Kaanapali 3 Manele Bay Dock and Anchorage
4 Kahului Maui 4 Ma~lo Wharf Anchorage
5 Lahaina Small Boat Harbor
6 Lahaina Roadstead
7 Maalaea Bay Small Boat Harbor
8 Kihei Beach Anchorage

~~Ki-OLAWNA

1584 W 30' 157' 30' 156'1

-47-

Kahului Harbor on Maui via the Pailolo Channel separating Molokai and Maui.
The westward trip may follow the reverse route. During our aircraft surveys
and our observations from boats, we have seen tugs with one or two barges in
tow, within a quarter-mile radius or less of pods of whales.

Aircraft Traffic

Two commuter airlines, Air Hawaii and Royal Hawaiian Airlines, fly
regularly between the islands of Maui, Lanai, Molokai, and Oahu, often
traversing the Auau and Kalohi Channels. During whale season, many of the
flights between Honolulu and Maui may intentionally pass south of Maui and
Molokai rather than than to the north of those islands, in order to view the
whales. The flights may pass directly over areas of greatest whale
aggregation. Pilots watch for whales and show them to their passengers.
Flights may be made at altitudes of 1,000 feet, sometimes lower. The final
approach to Kaanapali Airport in normal trade winds is from the southeast,
taking the aircraft very low over' waters near Kaanapali, where whales are
commonly seen. As a passenger, one may occasionally overhear exchanges of
information between pilots or between pilot and control tower at Kaanapali,
reporting locations of whales. Pilots may divert their aircraft to view the
whales reported and may orbit a group of whales one or more times as
passengers watch or photograph. However, activities such as these appear to be
decreasing in frequency in response to an increased awareness by the pilots of
the potential for disturbing the whales.

Table A-3 gives the operating schedule for Royal Hawaiian Airlines and Air
Hawaii. Royal Hawaiian flies 33 times daily to Kaanapali airport, and 19 times
daily to Kahului Airport. The trip to Kahului may be made along the southern
coast of west Maui, at the pilot's discretion, and then into Kahului across
the "neck" separating west and east Maui. Air Hawaii does not fly to Kaanapali
Airport, but like Royal Hawaiian may fly south of Maui rather than along its
northern shoreline during some of its 20 daily trips to Kahului. At present,
the airport at Kaanapali is privately owned, and normally available only to
Royal Hawaiian aircraft. A new, larger airport open to all airlines, including
the Aloha and Hawaiian Air jet fleet, is planned for this area in the near
future, and will undoubtedly lead to greatly increased air traffic in the Auau
channel area.

Two helicopter companies, Maui Helicopters and Western Helibirds,
advertise whale-watching excursions, as does one seaplane company, Seaplane
Safari. These companies are listed in Table A-2, and contribute an unmeasured
quantity to the total amount of whale-watching activity. The flight patterns
and observation techniques of these chartered aircraft have not been observed
by us.

Military air traffic occurs around the island of Kahoolawe, which is used
regularly as a target island for bombing practice. The flight paths of these
aircraft as they make their bombing runs have not been monitored by us, but it
can be assumed that a number may fly at low altitude over portions of the Auau
Channel. It is not known whether any bombs may inadvertantly fall into waters
adjoining the island. The airborne sounds of explosions from air strikes on
Kahoolawe can at times be heard on the nearby islands, but it is not known to
what degree the noise or vibration may penetrate into adjoining waters.

-48-

Table A-2

Sightseeing Tours Advertising Whale-watching

Vessel Type Length Location Frequency

Scuba King Power 38? Lahaina As chartered
Maui Adventures Power 30 Lahaina As chartered
Seahorse Sail 52' Kaanapali Twice daily
Scotch Mist Sail 36' Lahaina Daily
Iconoclast Sail 34 Lahaina Twice daily
Vida Mia Power 61 Lahaina Twice daily
Viajero Sail 65' Lahaina Twice daily
Windjammer Sail 70' Lahaina Sat. & Sun.
Maui Helicopters Helicopter -- Lahaina As chartered
Western Helibirds Helicopter -- Kihei As chartered
Seaplane Safaris Aircraft -- Lahaina As chartered

Table A-3

Number of Daily Flights by Commuter Airlines into Airports within
Four-Island Region

Commuter Molokai Lanai Kaanapali Kahului Total

Air Hawaii 14 13 0 20 47
Royal Hawaiian
Airlines 30 12 33 19 94

Totals 44 25 33 39

-49-

Publicity Given Whales

The potential impact of human activities on the whales can be expected to
increase with the heightened publicity given the whales. Although some
publicity warns against harassment, much of it is geared toward generating
interest in whale-watching or related activities, especially from boats. There
is no doubt that such publicity has increased greatly over the last three to
four years. Films on the Hawaiian humpback whale have been shown on national
television, and the whales have been described in a variety of magazines
having large circulation. Whale posters can be found throughout the Maui
tourist area. There is a continuous showing of a humpback whale film aboard
the whaling museum Cartha_ inian, docked at the entrance to Lahaina Harbor.
The vessel is being restored as a whaling ship under the auspices of the
Lahaina Restoration Foundation. One can additionally expect a large number of
whale talks, slide shows, and films by visiting or local photographers
throughout each season.

In general, there appears to be a rapidly growing recognition on Maui
that the whales can be important to the tourist industry, providing an
additional inducement for visiting Maui in winter. In addition to the direct
business generated by whale-watching charter boats or aircraft, many shops
sell whale memorabilia, such as whale books, T-shirts with whale slogans,
scrimshaw, whale and dolphin figurines, whale jewelry, and even narwhal tusks.
The number of shops featuring whale items seems to be increasing rapidly.

Free tourist publicati6ns, available throughout Maui, amplify the
publicity given the whales. A painting of a humpback whale was featured on the
front page of the complimentary publication, "Holiday on Maui," for the week
of February 2-8, 1979. Its caption read in part: "Join a whale-watching cruise
off Lahaina, or read about Maui's whales in National Geographic . . ." The
January 4-10, 1979 issue of the complimentary 'Hawaii Tourist News" also
featured a front-page story on the whales titled "Biggest Visitors are Back."
The story gives details of whale-watching cruises, including prices. A
conservation note is appended to the end of the item. The January 6-10 issue
of the free "Guide to Maui" urges all to "Go Watch the Whales." Charter boats
are mentioned and recommended.

Realistically, whale publicity can be expected to increase each season.
During the winter, Maui hotels are filled to capacity. Many more condominiums
and hotels are under construction as Maui explodes into a speculative fever
built around the tourist business. The implication seems clear; that without a
great deal of education and intelligent guidelines, what is good for Maui may
not necessarily be good for the whales.

Spatial Distribution of Whales

Figures A-2 and A-3 show, respectively, the relative density of all whales
(including calves), and of calves alone, within specified subregions of the
four-island region. For each subregion, density figures were calculated as the
total number of all whales (Figure A-2) or the total number of calves (Figure
A-3) counted during nine aerial surveys in 1977 and six aerial surveys in 1978.
The surveys were spaced at approximate two-week intervals between January and
April. Adjustments were made in the calculations to compensate for differences

22*

~~~~~~~~~~~~~~~~~LNA

30' -L Lowest
K AHOOL AWE

,S5ll W 30' 157" 30' 156"

Fig. A-2. Relative Density of All Whales (1977-1978)

30'- ~ OAHU

LILowest
K AHOOL AWE

1580 W 30' 157" 30' 1566

Fig. A-3. Relative Density of Calves (1977-1978)

-52-

in sizes of the various subregions. The mean and standard deviation (SD) of
the distributions were obtained for all whales and for calves alone, for the
two years combined. Subregions with densities greater than two SD's above the
mean are shown by the darkest shading; those between one and two SD's above
the mean are shown in medium shading; those between the mean and one SD are
shown with the lightest shading; finally, those below the mean are shown in
white. It is apparent that subregions of greatest calf density tend to
correspond with those of greatest overall whale density, although there are
some exceptions. The area between Olawalu and McGregor Point on Maui, although
densely populated by adult whales, shows relatively few calves.

Of particular note is the sector bordering Lahaina Harbor. This is an
area of least density of both total whales and calves, although bordered by
areas of higher density. Is this a case in which intense maritime activity has
produced an avoidance of the area by the whales? In general, there seems to be
a negative correlation between areas of heavy whale usage and heavy human
usage. For example, the remote, almost uninhabited, north and northeast coasts
of Lanai are areas of heavy whale usage. In the main text of this report,
further instances are given of the negative correlation between human and
whale use of areas.

Temporal Distribution of Whales

Figure A-24 shows the temporal distribution of whales for the 1977 and 1978
seasons, based on aerial survey data. The data are for all areas of Hawaii
combined. Results for the two seasons are remarkably similar. Peak numbers of
whales are present in Hawaiian waters during the third and fourth weeks of
February. At those times, encounters between whales and human maritime
activity may be expected to be at a maximum.

Summary and Conclusions

The results of the survey of marine and air traffic in the four-island
region, together with the distributional pattern of the whales, raises concern
for, the well-being of the whale population. .Specifically:

a) A full 47% of the 1978 sightings of whales by aircraft survey
were in the Kalohi and Auau Channels. Air and marine traffic
through or over these channels is common (Table A-3).
b) Of the commercial and private boats located in the larger bays
and harbors within the four-island region during January of
1979, approximately 69% were berthed in Maui's Lahaina Harbor,
or in Maalaea Bay. These areas border subregions in which
many whales are found during the winter season.
c) The presence of whales near resort areas has been well advertised
and whale-watching is becoming an important commercial venture.
The port of Lahaina provides the bulk of the tourist whale-watch
charters.

It is clear that there are significant regions of overlap between areas
used by marine and air traffic and areas of dense whale concentration within
the four-island region. A high potential for harassment exists, and may be

0 - 1977 data. 415 whales
sighted during 9 surveys.

- 1978 data. 638 whales
sighted during 6 surveys.

I ! - I _ I It . ! -- I _ ! I. 1. .... I J x 7.. .. 1
Jan Jan Jan Jan Feb Feb Feb Feb Mar Mar Mar Mar Apr Apr Apr Apr
$ 15 22 29 5 12 1, 26 5 12 19 26 2 9 16 23
SIH'FING DATES
Fig.A-4. Relative abundance of whales, all islands of Hawaii combined, from January through April,
during 1977 and 1978. The number of whales counted in each survey date is expressed as a
percentage of the total whales counted over all surveys in a season.

expected to increase as interest in the whales increases. Given the small
numbers of North-Pacific humpback whales, and the absence of data indicating
strong trends towards recovery, it may be wisest to proceed as if conditions
for negative impact were present.

A program to prevent harassment will require co-ordinated efforts at
local and Federal levels to achieve (a~) greater education of the public and
private sector with regard to the socio-ecology of the humpback whale and the
need to regulate access to whales in Hawaiian waters; (i.) effective
implementation and enforcement of conservation goals; and (c~) additional
research efforts to identify habitat usage and requirements of the whales, the
functions of their behaviors, the structure of their social organization, and
the manner in which the well-being of the whale population may be threatened
by marine and aerial traffic.

The most effective co-ordination may be accomplished through an appointed
'~Recovery Team," a standing committee of specialists whose function is to
monitor the status of the whales and their habitat, to evaluate the successes
or shortcomings of implemented conservation programs, to identify areas needing
further study, and to make recommendations to local, State, and Federal
Agencies. The Recovery Team should concern itself with the status of the
whales over their summer range, as well as in the winter breeding habitats.

References

Chittleborough, R. G. 1953. Aerial observations on the humpback whale
Menaptera nodosa (Bonnaterre), with notes on other species. Austr.
J. Mar. Freshw. Res., 4:219-226.

Dawbin, W. H. 1966. The seasonal cycle of humpback whales. Pages 145-170
in K.S. Norris, ed. Whales, Dolphins and Porpoises. University of
California Press, Berkeley.

Herman, L. M. 1977. Humpback whales in the Hawaiian breeding waters:
Behaviors. Manuscript.

Herman, L. M. 1980. Humpback whales in Hawaii: A study in historical
ecology. Pac. Sci., in press.

Herman, L. M. & R. C. Antinoja. 1977. Humpback whales in the Hawaiian
breeding waters: Population and pod characteristics. Sci. Rep.
Whales Res. Inst., 29:59-85.

Nishiwaki, M. 1972. General biology. Pages 3-204 in S.H. Ridgway, ed.
Mammals of the Sea: Biology and Medicine. Charles C. Thomas,
Springfield, Illinois.

Scammon, C. M. 1874. The Marine Mammals of the Northwestern Coast of
North America. Putnam, New York.

Shallenberger, E. W. 1976. Report to Sea Flite and Sea Grant on the
population and distribution of humpback whales in Hawaii. (mimeo).