CETACEAN ASSESSMENT AND ECOLOGY PROGRAM:
International Whaling Commission Scientific Committee Meeting
Sue Moore (NMML Director), Paul Wade (Cetacean Assessment and Ecology Program
Leader), and reserach biologist Nancy Friday attended the International
Whaling Commission (IWC) Scientific Committee Meeting, 26 May - 6 June
2003, in Berlin, Germany, prior to the 55th Annual Meeting of the IWC.
Cook Inlet Beluga Survey
Sightings of beluga whales in Cook Inlet, Alaska, during the standard aerial surveys conducted in June 2003.
Sighting locations are typical for this time of year as evidenced by similar surveys conducted over the past decade.
(click image to enlarge.)
NMML biologists and the NMFS Alaska Regional Office, Anchorage, conducted
an aerial survey of the beluga population (Delphinapterus leucas) in Cook
Inlet, Alaska, from 31 May to 12 June 2003. The 61-hour survey was flown
in a twin-engine, high-wing aircraft (an Aero Commander) at an altitude
of 244 m (800 ft) and a speed of 185 km/hr (100 kt), consistent with previous
NMFS surveys conducted in Cook Inlet each year since 1993. The flights
included one or more surveys of coastal areas (flown 1.4 km offshore) around
the entire inlet and 1,145 km of transects across the inlet, effectively
searching 25% of all the surface area of Cook Inlet but covering 100% of
the coastal areas. Paired, independent observers searched on the left
(coastal) side of the plane, where virtually all beluga sightings occur,
while a single observer was on the right. A computer operator/data recorder
was also on the left side. After finding beluga groups, two pairs of observers
each made four or more independent counts of each group during a series
of aerial passes. In optimal viewing conditions on six different days,
the median counts were 0-41 belugas in the Susitna Delta (between the Beluga
and Little Susitna Rivers), 30-94 in Knik Arm (there appeared to be exchanges
of whales between the Susitna area and Knik Arm), and 21-65 in Chickaloon
Bay (including the western end of Turnagain Arm). No belugas were seen
elsewhere. This sighting distribution has been consistent in June or July
most years since 1996. The sum of the median aerial estimates (a very
rough but quick index of relative abundance, not corrected for estimates
of missed whales) for June 2003 is 174 belugas. This is below index counts
for years prior to 1998 (305 in 1993, 281 in 1994, 324 in 1995, 307 in
1996, and 264 in 1997), but it is essentially the same as counts during
the past 4 years (193 in 1998, 217 in 1999, 184 in 2000, 211 in 2001, and 192 in 2002).
By Dave Rugh.
Bowhead Whale Photography
An adult bowhead whale with its newborn calf during the spring migration past Barrow, Alaska.
(Photo by Dave Rugh.)
As part of NMFS management of the western Arctic stock of bowhead whales
(Balaena mysticetus), surveys were conducted 11 April to 6 June 2003 near
Barrow, Alaska, to collect aerial photographs throughout the stock's spring
migration into the Beaufort Sea. Most of the funding for this study was
provided through a grant to the North Slope Borough (NSB), supplemented
by support from the NMML. Support included participation by John Brandon
(under contract through NMML's Cetacean Assessment and Ecology Program)
for the entire season and by Sue Moore (NMML Director) for 1 week. The
project is a continuation of photographic surveys conducted by NMML between
1985 and 1992.
The 2003 survey was carried out in an Aero Commander, a twin-engine, high-wing
aircraft, generally flown at altitudes of 130-170 m (400-500 ft) and a
speed of 185 km/hr (100 kt). Surveys were flown almost every day, for
a total of 174 hours in 55 days, with very little time lost due to weather.
The nonsystematic search effort was conducted along open water areas north
and east of Point Barrow, avoiding whaling camps to the west. After finding
bowheads, a series of aerial passes was made to obtain vertical photographs
through a port in the floor of the aircraft. A hand-held, medium format
camera was used to collect 1,150 photographs. The whale images will be
studied to identify individual animals.
Reidentification of animals between years will help answer questions about
abundance, survival rates, and calving intervals.
A similar survey, following the same protocol used in 2003, is planned
for spring 2004. The objective is to provide the "recapture" portion of
the "mark-recapture" study, where "marks" refer to animals with identifiable
markings on the dorsal surface. All survey activities are conducted in
cooperation with the NMFS Alaska Regional Office, the Alaska Eskimo Whaling
Commission, and the NSB.
By Dave Rugh.
False Pass Killer Whale Survey
In collaboration with the North Gulf Oceanic Society (NGOS), the NMML participated
in a killer whale survey mid-May through early June 2003 on a 42-ft fishing
vessel, the Lucky Dove. Research effort focused on locating transient
(mammal-eating) killer whales in and around the False Pass area between
the Alaska Peninsula and the Aleutian Islands.
Photo-identification, biopsy, acoustic recording, and prey-sample data
collected during the survey will be used to determine abundance, distribution,
stock structure, ecology, eco-type and what, if any, impact killer whale
predation has on the declining western stock of Steller sea lions. These
data provide some new baseline information about killer whales in the Alaska
Peninsula/Aleutian Island area and are a valuable addition to what is currently
known about killer whales off Alaska, British Columbia, and the west coast
of the United States.
By Lori Mazzuca.
POLAR ECOSYSTEMS PROGRAM:
Harbor Seal Abundance and Distribution in Cook Inlet
Aerial photograph of harbor seals during pupping, Kamishak Bay, Cook Inlet, Alaska.
(Photo by John Jansen.)
The NMML Polar Ecosystems Program has begun a two-part study of harbor
seals in Cook Inlet under an Interagency Agreement between the Department
of the Interior's Minerals Management Service (MMS) and NMFS. The first
part of the study focuses on estimating seal abundance and mapping the
distribution of haul-out sites over a complete annual cycle with an emphasis
on two, key life history events: pupping (June) and molting (August).
The second part of the study focuses on identifying the factors that affect
seal haul-out behavior at different sites in Cook Inlet and to quantify
the relationship between these factors and haul-out patterns. These studies
are needed by the MMS to support environmental risk assessments, environmental
impact statements, and other documents pertaining to potential gas and
oil development in the Cook Inlet planning area. The studies will also
benefit NMFS in support of stock assessments and recovery of protected species.
To estimate harbor seal abundance and distribution, the first of six planned
surveys was conducted 11-19 June 2003 to coincide with pupping. The survey
area covered the east and west coastlines of Cook Inlet, stretching from
the Barren Islands in the south to the East and West Forelands north of
Kalgin Island. Surveys were flown over a 4-hour period centered at low
tide, when the largest number of seals are expected to be hauled-out.
The entire coastline was surveyed twice: at different tidal states (high-low
and low-low) to increase coverage of potential haulouts, since some sites
are not accessible at the lowest tides while others are usable only then.
Coupled with this reconnaissance, site-to-site sampling yielded a total
of 6-8 photo surveys at each haulout. Survey photographs are currently
being counted. The next survey is scheduled for August 2003 to coincide
with the seals' molting season.
To examine seal haul-out behavior, a remote camera system is being developed
to count seals from images recorded at regular intervals under varying
environmental conditions. In preparation for deployments, NMML researchers
evaluated potential camera sites 14-25 June on Augustine Island, where
two accessible and viewable beach haulouts totaling several hundred animals
had been mapped previously.
Several camera sites were identified, and trails were cleared to allow
better access. The researchers conducted hourly counts of seals to gain
preliminary data on haul-out behavior and spatial organization of seals
within the haul-out areas. Field deployment of the camera systems is planned
to begin in October 2003.
By Peter Boveng, John Jansen, and Mike Simpkins.
Quarterly April-June 2003 sidebar
April - June 2003
Auke Bay Lab