AMJ 2000 Quarterly Rpt. AMJ 2000 sidebar
Report for April-May-June 2000)
Three marine mammal observers conducted a
cetacean survey from 9 June to 2 July 2000 aboard
the NOAA ship
Freeman. The survey was a piggyback
project during a RACE Division acoustic-trawl survey
for walleye pollock. The primary objective of
the cetacean survey was to find northern right
whales and obtain photographs for individual
identification and biopsy samples. The
secondary objective was to collect line-transect
data for all whales, dolphin, and porpoise species
for abundance estimation. Other marine mammal
sightings such as walrus, sea otters, and pinnipeds,
were also recorded for distribution information.
The Miller Freeman is a 215 ft long research
vessel and the survey was conducted while the ship
was at a speed of approximately 11.8 kts. The
cetacean survey included part of the transit from
Kodiak Island to the first acoustic trawl line in
Bristol Bay, the 18 north-south transect lines
proceeding from east (long.160° 20´W) to west
(long. 171° 20´W), and part of the transit to
Dutch Harbor. The transect lines were 20
nautical miles (nmi) apart and ranged from
approximately 85 km to 290 km in length and covered
the southwestern portion of Bristol Bay and across
the shelf (the southern ends of the lines along the
shelf edge) to just west of the Pribilof Islands.
Number of marine mammal sightings and
individuals observed during the survey aboard
the NOAA ship Miller Freeman.
Number of Sightings
Number of Individuals
Steller sea lion
Northern fur seal
The cetacean survey was conducted
from the flying bridge where two observers searched
through 25x150 power binoculars at starboard and
port stations. A data recorder also searched
by equally scanning both sides of the trackline with
the naked eye, using Fujinon 7x50 hand-held
binoculars to confirm sightings. The observers
rotated positions every half hour during a 2 hour
shift, followed by a half hour break. The
survey was suspended when the ship stopped for
fishing operations, during inclement weather, and
when light levels were too low for efficient
A total of 2,598 km of trackline was surveyed.
Northern right whales were not observed. The number
of other recorded marine mammals are listed in here
in Table 1.
By Janice Waite.
Seals in Inland Transboundary Waters
The first phase of a cooperative
project on harbor seal assessment, distribution, and
foraging behavior conducted by the NMML, Washington
Department of Fish and Wildlife and the Canadian
Department of Fisheries and Oceans was conducted
16-19 May 2000 at Boundary Bay, British Columbia.
Twenty-five harbor seals were captured and
released, including 15 that were fitted with
time-depth recorders, VHF head mounts and VHF
flipper tags. The project is part of an effort
to determine if harbor seal haul-out behavior has
changed in the last 10 years, or if the apparent
leveling of the harbor seal population in the inland
waters is real. In addition, the study will
provide a comparison of methods for determining a
correction factor to account for seals in the water
during aerial surveys and will provide information
on movements and foraging behavior in transboundary
By Harriet Huber.
Pinniped-Salmonid Interactions in Ozette
River and Lake
The Lake Ozette sockeye salmon (Oncorhynchus
nerka) population was listed as threatened under
the Endangered Species Act in March 1999. For
the last 2 years, the NMML and the Makah Tribal
Fisheries Service in cooperation with the National
Park Service, have been conducting research on the
possible impacts of pinniped predation on sockeye
recovery. During May and June 2000, field
research was conducted both at the mouth of the
Ozette River and upriver at the fish weir to
identify the quantity, timing, and location of
predation. At the river mouth, 83 sockeye were
captured, anesthetized, and tagged. Each fish
was examined for marine mammal scars, and a digital
photograph was taken of each side of the fish.
Upriver at the fish weir, a fish trap was
monitored 24 hours a day and all sockeye were
counted and examined through a floating glass
viewport. Tagged fish were removed,
anesthetized, examined for scars, photographed, and
then released. A sample of fish received an
internal sonic tag to enable tracking of the fish on
the spawning grounds in the lake.
By Jeff Laake.
The attachment of satellite-linked transmitters is
an important technique for obtaining information on
the movements and diving behavior of cetaceans.
However, until recently most attachments
lasted only several months, which does not provide
information about seasonal and long-term movements.
Using bioengineering principles, NMML
researchers have studied the material properties of
the dorsal fin and attachment pins of the
transmitters, and the drag and load created by
different tag attachments. Research has shown that a
paired-side mount configuration produced the least
amount of stress at the pin sites.
Scientists were able to monitor a Dall’s
porpoise successfully tagged using the
paired-side mount technique, from early May 1999
through May 2000, a duration of 380 days.
This Dall’s porpoise was initially
tagged in Haro Strait and subsequently moved to the
outer coast of Vancouver Island in late spring 1999,
returned to inland waters during the fall and winter
of 1999/2000, and has now returned back to the outer
NMML researchers have also developed a telemetry
system for Keiko the killer whale using a similar
approach in tag design. In May and June
researchers finalized the tag configuration and
custom fit the package to Keiko’s fin. Like
other packages that have been developed, it
incorporates a satellite-linked and VHF transmitter
which will allow Keiko’s movements to be monitored
if he is released.
By Brad Hanson.
Killer Whale Workshop Spring 2000
On 1-2 April 2000, a killer whale workshop was
held at the AFSC facilities in Seattle, Washington.
Sponsors of the workshop were the NMML, Center
for Whale Research, Six Flags Marine World, and the
Whale Museum. Contributions were made by the
Department of Fisheries and Oceans (DFO Canada) and
the American Cetacean Society. The purpose of
the workshop was to inform participants about the
current status of southern resident killer whales
and help the research community coordinate future
research. The workshop focused on four areas
population dynamics of eastern
North Pacific killer whales
stock structure of eastern North
Pacific killer whales
possible factors influencing
killer whale populations
In addition to
several oral presentations covering these topics, 13
background documents were also submitted by
At the conclusion of the workshop, several areas
needing continued research were identified
including: studies of photo-identification work;
estimates of historical population levels;
identification of the relation between prey base and
population status; increased attention on winter
feeding and feeding depths in the summer; studies of
the effects of pollution on reproduction and
survival; and determination of the effects of whale
watching. Once existing tissue samples are
analyzed and specific hypotheses are developed for
contaminant and genetic investigations, additional
biopsy darting may be warranted. The
importance of understanding the population dynamics
of transient eastern North Pacific killer whales was
also recognized, as this population is more
contaminated than the southern residents. Finally,
a correlation in population trends between the A and
J clans was reported, as these two pods are from
different stocks; the population dynamics of
northern residents also warrants research to help
clarify what factors are contributing to the decline
of southern residents.
By Christy Sims and Marilyn Dahlheim.
Alaska Killer Whale Photography and Biopsy
National Marine Mammal Laboratory staff working
jointly with the North Pacific Groundfish Fishery
Observer Program implemented a special project this
year that uses selected fishery observers working
aboard longline fishing vessels in the Aleutian
Islands/Bering Sea to collect photographs and biopsy
samples of North Pacific killer whales on an
opportunistic basis. Much concern has been raised
recently about the population size and stock
structure of these killer whales. Minimum
counts of killer whales, ranging from the western
Gulf of Alaska to the Bering Sea (to include the
eastern and central Aleutian Islands region) have
been obtained through photo-identification studies.
Photographic analyses of data collected through
dedicated studies and through the efforts of the
fishery observer program have resulted in the
identification of 400 individual whales, to date.
The data collected through the project will
further aid researchers in determining killer whale
stock structure, population size, and contaminant
The first observer to participate in this study was
selected, trained, and completed one cruise during
April-June 2000. During this cruise he
successfully photographed several killer whales and
collected two biopsy samples near Dutch Harbor,
Alaska in June. NMML researchers are presently in
the process of analyzing these new data.
By Anita Lopez.
Search for Harbor Seal Study Site in
NMML staff, along with a representative of the
Alaska Department of Fish and Game (ADF&G), used
N. Cobb during 8-14 June 2000.
The objectives of the trip were to
search for a potential, long-term harbor seal study
site in Southeast Alaska and to determine the stage
of pupping at several selected haul-out sites.
Several sites were identified as potential sites for
long-term camps and observing seals and deploying
remote video monitoring stations. These
included Rookery, Echo, Cedar Shakes, and Beauclerc
Islands, all south of Juneau and within close
proximity to Petersburg or Wrangell for logistics
support. Seal numbers were variable at these sites,
ranging from approximately 50 to 500, and in
all cases the proportion of female-pup pairs was
Both the Tracy and Endicott Arms glacial fjords were
transited, assessed for camp/video potential, and
the harbor seals were counted. In both cases
floating ice that had calved from the glacier slowed
the Cobb’s progress through the fjord. Six
hundred to 1,000 seals were counted in Tracy Arm and
roughly 700 in Endicott Arm. Again the
proportion of female-pup pairs was high. The
Tracy Arm area also showed good potential for a
long-term camp and remote video site.
By Dave Withrow and Jack Cesarone.
Arctic Ecosystems Program Ice Seal Surveys
NMML’s Arctic Ecosystems Program conducted aerial
surveys from 21 May to 1 June 2000 to assess
distribution and abundance of ringed and bearded
seals in northwestern Alaska. These surveys
complemented similar surveys conducted by NMML in
May-June 1999. In both years, the coastline of
the Chukchi Sea was surveyed east of Ikpek Lagoon
(near Shishmaref) and north to Barrow. Survey
lines were flown perpendicular to the coast with
most lines 20 nmi in length, supplemented by a
sample of longer lines (100 nmi) to assess off-shore
seal densities. Ringed seal densities were
highest south of Kivalina and northwest of Kotzebue.
Bearded seals were generally seen at distances
greater than 20 nmi from the coast, although they
were present in relatively high densities within 20
nmi of shore in the area south of Kivalina.
Because the aerial surveys only observed seals on
the ice surface, a correction factor is needed to
account for seals that were in the water at the time
of the survey. To develop this correction
factor, three ringed seals were captured and
instrumented with satellite tags. Data from
these instruments will provide information on the
amount of time the seals spend in the water and will
allow NMML scientists to adjust the aerial survey
numbers to account for seals not hauled out on the
ice when these surveys took place.
By Lisa Hiruki.