Mass-mortality of guillemots (Uria aalge) in the Gulf of Alaska in 1993
Piatt JF and Van Pelt TI. 1997. Mass-mortality of guillemots (Uria aalge) in the Gulf of Alaska in 1993. Marine Pollution Bulletin. 34(8):656-662
During the first six months of 1993, about 3500 dead and morbund guillemots (Uria aalge) were observed through-out the northern Gulf of Alaska Coast. Mortality peaked during March. Highest numbers were observed in western Prince William Sound and along the south coast of the Kenai Peninsula. Large flocks of live guillemots gathered in nearshore waters, in contrast to most winters when guillemots reside offshore. Most guillemots recovered were extremely emaciated and sub-adult. Based on carcas deposition and persistence experiments, we calculated that about 10900 birds eventually came ashore on beaches that were surveyed. Even if most birds killed made it to shore, only a fraction of beaches in the Gulf of Alaska were Surveyed and we estimate that a minimum total of 120000 guillemonts died. Results of other investigations on potential causes of mortality (biotoxins, pathogens, parasites, metals, etc.) were either negative or inconclusive, and necropsies lead us to believe that starvation was the proximate cause of death. Reduced food availability could have been realted to anomalous sea condistions found during the prolonged 1990-1995 El Nino-Southern Oscillation event.
- Type
- Journal Article
- Authors
- Piatt, John; Van Pelt, Thomas
- Units
- GLBA , KEFJ , KLGO , SEAN , SITK
- Keywords
- auks, Birds, Guillemots, Gulf Of Alaska, Seabirds, Uria Aalge