Density and productivity of bald eagles in Prince William Sound, Alaska, after the Exxon Valdez oil spill
- Brigham Young Univ., Provo, UT (United States)
- Alaska Biological Research, Inc., Fairbanks, AK (United States)
Helicopter surveys were conducted in Prince William Sound (PWS) to assess the effects of the 1989 Exxon Valdez oil spill on the reproductive success and densities of bald eagles (Haliaeetus leucocephalus) one and two years after the spill (1990 and 1991). Densities of bald eagles were compared between an oiled area in southwestern PWS and an unoiled area in northern PWS. In all surveys (four in 1990, one in 1991) densities of eagles in the oiled areas generally were similar to or higher than those in the unoiled area. Reproductive success was compared between nesting territories that were oiled within 1 km of nests and nesting territories that were unoiled. In 1990, all measures of nest productivity, nest occupancy, and nesting success were similar between oiled and unoiled territories. In 1991, however, the number of young per successful nest was lower in oiled territories. The number of successful nests was slightly lower in 1991 than in 1990 in oiled territories but was significantly lower in 1991 in unoiled territories. Comparisons of nest occupancy and nesting success could not be made in 1991 because early surveys were not conducted. Differences between areas, territories, and years could not be attributed to oil, but rather appeared to be related to natural annual variability. Overall, no demonstrable effects of the oil spill on eagle density or reproduction could be detected in PWS one and two years after the spill. 70 refs., 1 fig., 3 tabs.
- OSTI ID:
- 382773
- Report Number(s):
- CONF-930442-; ISBN 0-8031-1896-1; TRN: 96:025732
- Resource Relation:
- Conference: 3. symposium on environmental toxicology and risk assessment, Atlanta, GA (United States), 25-28 Apr 1993; Other Information: PBD: 1995; Related Information: Is Part Of Exxon Valdez oil spill: Fate and effects in Alaskan waters; Wells, P.G.; Butler, J.N.; Hughes, J.S. [eds.]; PB: 961 p.; ASTM special technical publication, 1219
- Country of Publication:
- United States
- Language:
- English
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