thumbnail

Seasonal and distributional patterns of seabirds along the Aleutian Archipelago

Marine Ecology Progress Series

By:
, , ,
DOI: 10.3354/meps07325

Links

Abstract

The Aleutian Archipelago is of global importance to seabirds during the northern summer, but little is known about seabird use of these waters during winter. We compare summer and winter abundances of seabirds around 3 islands: Buldir in the western, Kasatochi in the central, and Aiktak in the eastern Aleutians. The density of combined seabird biomass in nearshore marine waters was higher in summer than in winter at Buldir and Kasatochi, but was higher in winter at Aiktak, despite the departure of abundant migratory species. Comparing foraging guilds, we found that only piscivores increased at the western and central sites in winter, whereas at the eastern site several planktivorous species increased as well. The only planktivore remaining in winter at the central and western sites in densities comparable to summer densities was whiskered auklet Aethia pygmaea. Crested auklet Aethia cristatella and thick-billed murre Uria lomvia showed the greatest proportional winter increase at the eastern site. The seasonal patterns of the seabird communities suggest a winter breakdown of the copepod-based food web in the central and western parts of the archipelago, and a system that remains rich in euphausiids in the eastern Aleutians. We suggest that in winter crested auklets take the trophic role that short-tailed shearwaters Puffinus tenuirostris occupy during summer. We hypothesize that advection of euphausiids in the Aleutian North Slope Current is important for supporting the high biomass of planktivores that occupy the Unimak Pass region on a year-round basis. ?? Inter-Research 2008.

Additional Publication Details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Seasonal and distributional patterns of seabirds along the Aleutian Archipelago
Series title:
Marine Ecology Progress Series
DOI:
10.3354/meps07325
Volume
357
Year Published:
2008
Language:
English
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
First page:
301
Last page:
311
Number of Pages:
11