Marine Mammals Working GroupSummary of Results

Ihor Hlohowskyj

North Aleutian Basin Information Status and Research Planning Meeting

Minerals Management Service

Anchorage, Alaska

November 28—December 1, 2006

2

Approach

Resource Identification focused on stocks (21)

– Listing status (threatened or endangered)

– Stock status (stable or changing)

– Availability of current abundance estimate

– % of stock potentially affected– Does stock provide for

subsistence use

Also examined regulatory linkage– MMPA

• Adversely change stock population trajectory

• Adversely affect subsistence use

– ESA• Result in jeopardy of listed

stock• Adversely modify critical

habitat– NEPA

• Potential for significant impacts

Identified 12 stocks for study

3

Nine Study Profiles Developed

Distribution, abundance, and habitat use of North Pacific right whales.

Seasonal acoustic monitoring of right whales and other endangered cetaceans.

Abundance, distribution and seasonal movements of humpback, fin, and other cetaceans.

Health assessment of stranding marine mammals in the NAB.

Steller sea lion seasonal distribution and diet.

Steller sea lion seasonal habitat use.

Harbor seal and spotted seal seasonal distribution.

Seasonal distribution and abundance of Pacific walrus.

Seasonal distribution and abundance of northern sea otter.

Subgroup did not consider O&G activities outside the NAB, but acknowledges that studies will be needed in appropriate areas.

4

Distribution, Abundance, and Habitat Use of North Pacific Right Whales

Objectives

– Characterize right whale habitat in and around the NAB.

– Characterize foraging behavior and prey distribution.

– Determine use of the NAB area, and movements throughout the Bering Sea and elsewhere.

– Characterize genetics, pollutant load, and diet.

– Establish a prey pollutant baseline.

Methods

– Satellite tagging of up to 15 whales.

– Biopsy samples collected during tagging for genetic, pollutant, and diet analyses.

– Collect copepods during oceanographic operations to establish a baseline for contaminants.

– Coordinate with other programs (e.g. Bering Ecosystem Study [BEST])

5

Seasonal Acoustic Monitoring of Right Whales and Other Endangered Cetaceans in the North Aleutian Basin Area

Objectives

– Monitor occurrence of right whales and other cetaceans year-round in the NAB.

– Assess the vocalization rate relative to the number of whales observed.

– Collect baseline ambient noise data, and assess changes in calling rates during and following seismic surveys.

Methods

– Deploy passive acoustic recorders in the NAB area for acoustic monitoring of whales and environment.

– Compare acoustic data with other planned surveys and satellite tagging studies to assess of the proportion of the local population that is vocalizing.

6

Abundance, Distribution, and Seasonal Movements of Humpback Whales, Fin Whales, and Other Cetaceans in the North Aleutian Basin.

Objectives

– Identify local distribution and occurrence of humpback, fin whales, and other cetaceans in lease area.

– Monitor movements and use of lease sale area and adjacent waters of individual fin and humpback whales.

– Assess the migratory destinations of individual whales and population identity.

– As possible, assess whether distribution and habitat use change in response to seismic survey activities

Methods

– Satellite tagging of individual fin and humpback whales

– Ship-based line-transect sightings surveys of cetaceans

7

Health Assessment of Stranding Marine Mammals in the North Aleutian Basin

Objectives

– Determine the normal spatial distribution and numbers of dead and moribund marine mammals by species, sex, and age along the coast of Bristol Bay and their cause of mortality.

– Evaluate contaminant and pathological conditions of the animals.

Methods

– Compile and evaluate existing survey data to identify stranding rate and “hot spots” where animals often come ashore.

– Monthly aerial surveys of the Bristol Bay shoreline during spring and summer to search for stranded marine mammals.

– If animal is accessible, conduct a necropsy and collect tissue samples.

– Analyze tissues for contaminants and pathogens and compare to data from healthy animals.

8

Monitoring Seasonal Distribution and Diet of Endangered Steller Sea Lions in the Southeastern Bering Sea and Eastern Aleutian Islands

Objectives

– Monitor abundance and pup production of sea lions in summer and winter on terrestrial haul-out and rookery sites in the eastern Aleutian Islands, western Gulf of Alaska, Sea Lion Rock/Amak, and in Bristol Bay.

– Record sightings of marked sea lions on terrestrial haul-out and rookery sites.

– Collect food habits information (scat) to determine sea lion prey species in the eastern Aleutian Islands and southeastern Bering Sea.

Methods

– Aerial survey photogrammetry to monitor terrestrial abundance.

– Summer vessel surveys in the eastern Aleutian Islands and southeastern Bering Sea to record sightings of marked animals and collect food habits information.

9

Seasonal Habitat Use by Endangered Steller Sea Lions of the North Aleutian Basin

Objectives

– Determine seasonal distribution of Steller sea lion in NAB and extent to which regions within the lease sale area are utilized for foraging.

– Characterize foraging depths and location and identify important foraging areas.

– Identify dispersal (migration) through the area to other haulouts surrounding NAB.

– Monitor the health and condition.

– Permanently mark individual animals for future studies.

Methods

– Capture animals and attach satellite telemetry transmitters.

– Measure health and condition of captured animals.

– GIS analysis of movement data.

– Archive collected physiological tissues for future analysis.

10

Seasonal Abundance, Movements and Marine Habitat Use of Harbor Seals and Spotted Seals in the North Aleutian Basin

Objectives

– Document the abundance, movements, foraging behavior, and marine habitat use of harbor and spotted seals in the NAB.

Methods

– Capture and instrument 20 harbor seals and 10 spotted seals in 2 successive years with satellite-linked data recorders.

– Seasonal aerial surveys for seals throughout the NAB to improve estimates of harbor seal and spotted seal seasonal abundance.

– Use study data with existing data in a comprehensive analysis of harbor seal and spotted seal distribution and habitat use in, or adjacent to, the NAB.

– Collect and archive tissue samples for future analyses.

11

Seasonal Distributions, Abundance and Habitat Use Patterns of Pacific Walruses in the North Aleutian Basin Planning Area

Objectives

– Document seasonal use patterns of coastal walrus haulouts in the vicinity of Lease Sale Area 92.

– Investigate haulout attendance, foraging patterns and locations.

– Use haulout attendance data to improve aerial survey design and provide sightability corrections for abundance estimates.

Methods

– Conduct bi-weekly aerial surveys of coastal walrus haulouts along the Alaska Peninsula (April-September).

– 25 satellite telemetry tags on walruses at coastal haulouts.

– GIS and probability-based models to define important foraging habitats.

12

Seasonal Distributions, Abundance and Habitat Use Patterns of Northern Sea Otters in the North Aleutian Basin Planning Area

Objectives

– Document seasonal distribution and abundance of sea otters both within and adjacent to the Lease Sale Area 92.

– Document seasonal habitat use patterns of sea otters both within and adjacent to the Lease Sale Area 92 area.

Methods

– Quarterly aerial surveys of sea otter distribution and abundance in Bristol Bay.

– Monitor individual sea otter movements and survival using implanted radio-telemetry instruments.

13

Study Prioritization

Study profile

Pre-lease exploration seismic (07-08)

Lease Sale/EIS Related Analyses (08-09) Development Production Duration (yr)

Total Cost ($K)

Distribution, abundance, and habitat use of North Pacific right whales

X       4 3,170

Seasonal acoustic monitoring of right whales and other endangered cetaceans

X       4 720

Abundance, distribution and seasonal movements of humpback, fin, and other cetaceans

X

 

    4 825

Health assessment of stranding marine mammals in the NAB X     4 875

Steller sea lion seasonal distribution and diet X     3 450

Steller sea lion seasonal habitat use X     3 940

Harbor seal and spotted seal seasonal distribution X     4 1,355

Seasonal distribution and abundance of Pacific walrus X     1 185

Seasonal distribution and abundance of northern sea otter X   3 1,200

Total 9,720