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

• Published in: Marine Ecology Progress Series
• Main Authors: Decker, MB, Hunt, GL
• Format: Article in Journal/Newspaper
• Language: English
• Published: eScholarship, University of California 1996
• Subjects: seabird distribution; tidal fronts; Uria lomvia; Uria aalge; murres; Bering Sea; Alaska; uria
• Online Access: http://www.escholarship.org/uc/item/2r4974ff

We investigated the foraging distribution of 2 species of murres (Uria lomvia and U. aalge) in relation to Acoustically Determined Biomass (ADB) and hydrographic 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.