Foraging by murres (Uria spp.) at tidal fronts surrounding the Pribilof Islands, Alaska, USA

• Published in: Marine ecology. Progress series (Halstenbek) Vol. 139; no. 1/3; pp. 1 - 10
• Main Authors: Decker, Mary Beth, Hunt, George L.
• Format: Journal Article
• Language: English
• Published: Inter-Research 29-08-1996
• Subjects: Aggregation; Biomass; Birds; Diet; Foraging; Marine; Musical intervals; Predators; Random allocation; Sea birds; Seas; Uria aalge; Uria lomvia; USA, Alaska; INE, Bering Sea
• ISSN: 0171-8630; 1616-1599
• DOI: 10.3354/meps139001

We investigated the foraging distribution of 2 species of murres (Uiia lomvia and U. aalge) in relation to Acoustically Determined Biomass (ADB) and hydrographie structure surrounding the Pribilof Islands, Bering Sea, Alaska, USA. The distribution and abundance of both murre species were similar; therefore, we combined data for thick-billed and common murres in the analysis. We found that murre densities were higher in frontal regions than in non-frontal regions. Maximum ADB was also found to be elevated in the frontal zone. Within frontal regions, high densities of murres were associated with regions containing relatively high levels of ADB. In contrast, we did not find significant correlations between murre density and ADB in the study area as a whole. We postulate that murres restrict their foraging to the frontal region because prey can be located more predictably within this zone than in other areas in the vicinity of the Pribilof Islands.