Using auklets to monitor the effects of global warming on the Bering Sea ecosystem : Detecting change in auklet food supply, productivity, and populations
Global warming is progressing more rapidly in polar-regions, and its effects are more pronounced at high latitudes than in other parts of the globe. Changing ocean conditions due to climate change are predicted to have dramatic impacts on marine foodwebs. Seabirds, as upper trophic-level consumers,...
| Main Author: | |
|---|---|
| Other Authors: | , , , , |
| Format: | Master Thesis |
| Language: | English unknown |
| Published: |
Oregon State University
|
| Subjects: | |
| Online Access: | https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/xg94hs90w |
| Summary: | Global warming is progressing more rapidly in polar-regions, and its effects are more pronounced at high latitudes than in other parts of the globe. Changing ocean conditions due to climate change are predicted to have dramatic impacts on marine foodwebs. Seabirds, as upper trophic-level consumers, provide a highly visible and easily studied component of marine food-webs. I studied two species of planktivorous seabirds, Least and Crested aukiets (Aethiapusilla and A. cristatella), which nest abundantly in rock crevices on talus slopes along the coastline of St. Lawrence Island, Alaska in the northern Bering Sea. My objectives were to (1) determine how indices of aukiet abundance based on counts of individuals on the surface of the breeding colony compare with population estimates from mark-resight techniques, and which method is more promising for detecting changes in breeding populations, (2) determine how density of nesting auklets varies within a breeding colony, (3) examine relationships among the taxonomic composition of aukiet diets, provisioning rates of food to young aukiets by their parents, and auklet reproductive success, and (4) test predictions from a previous study by Gall et al. (in press) regarding the effects on nesting success of the prevalence of certain prey types in the diet of Least and Crested aukiets. I conducted this research at two large, mixed-species aukiet colonies near the village of Savoonga during the 2003 and 2004 nesting seasons. |
|---|