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Project Information

Title: Assessment of Injuries to Killer Whales in PWS

Project Year and Number: 1992: MM02

Other Fiscal Years and Numbers for this Project: 1991: MM02, 1990: MM02, 1989: MM02

Principal Investigator (PI): Marilyn Dahlheim, NOAA

Assisting Personnel: Craig Matkin

Research Location: PWS/KAP

Restoration Category: Damage Assessment

Injured Resources Addressed: Killer Whales

Abstract: Photo-identification studies of individual killer whales inhabiting Prince William Sound were collected from 1989-91 to determine the impact of the spill on whale abundance and distribution. Concurrent photo-identification studies were also conducted in Southeast Alaska to determine if PWS killer whales were displaced to other areas. Despite increased effort, the number of encounters with PWS killer whales appears to be decreasing. Analysis of photographic data revealed 14 animals missing from AB pod over the three-year period. Mortality rates for AB pod ranged from 3.1% in 1988 to 19.4% in 1989, 20.7% in 1990, and 4.3% in 1991. Mortality rates on the order of 20% are unprecedented for North pacific Ma whales. No new calves were born into AB pod in 1989 or 1990. There was one calf born in 1991 and two born in 1992. AB pod size in 1988 was 36; in late 1992 the pod had 25 members. The cause(s) of the disappearance of 14 killer whales from AB pod is unknown. We assume, that the whales are dead from natural causes, a result of interactions with fisheries, from the spill, or a combination of these causes.


Geographic Regions Prince William Sound
Species Marine Mammals - Cetaceans (whales, dolphin, porpoises)
Fields of Expertise Ecology

Proposal: View PDF (18 KB)

Funding Recommendations: View

Funding Detail For: 1992

Quarterly Project Tasks For: 1992

Annual Report: 1992: Not Applicable

Final Report: View

Publications from this Project: None Available

More information may be available for this project under other years:

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Project Number Proposal Annual Reports Final Report Data
1991: MM02 Not Available 1991: Not Applicable
View See Project MM02
1990: MM02 Not Available 1990: Not Applicable
See Project MM02 See Project MM02
1989: MM02 Not Available 1989: Not Applicable
See Project MM02 See Project MM02