Spatial and temporal variation in the diet of Steller sea lions in the Kodiak Archipelago, 1999 to 2005

Abstract

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 360:265-283 (2008) - DOI: https://doi.org/10.3354/meps07383 Spatial and temporal variation in the diet of Steller sea lions in the Kodiak Archipelago, 1999 to 2005 Jane McKenzie*, Kate M. Wynne University of Alaska Fairbanks, School of Fisheries and Ocean Science, 118 Trident Way, Kodiak, Alaska 99615, USA *Email: janemckenzie@malpage.com ABSTRACT: Spatial and temporal variation in the diet of Steller sea lions Eumetopias jubatus was investigated using scat (fecal) samples collected from 4 regions in the Kodiak Archipelago. Over 2700 scats with identifiable prey were collected from the northern, eastern, southern and western sides of Kodiak Island from 1999 to 2005. Of 76 prey types identified using hard remains, the most important species in terms of frequency of occurrence and numerical abundance were Pacific sand lance Ammodytes hexapterus, walleye pollock Theragra chalcogramma, arrowtooth flounder Atheresthes stomias, Pacific cod Gadus macrocephalus, salmon Oncorhynchus spp., and Pacific herring Clupea pallasi. Significant differences in diet composition were found among regions, seasons, and years, suggesting that the diet of sea lions is strongly influenced by local and temporal distributions and abundances of prey. Herring dominated scat collections from the west coast and accounted for most (14 to 30%) of the differences in regional diet in spring and winter. Annual variation in diet was relatively low in winter, whereas spring and fall diets varied from year to year, with regional-specific shifts in dominant prey. Results from our study generally agree with diet studies conducted in the 1990s, but differ markedly in the relative importance of the major prey species. KEY WORDS: Eumetopias jubatus · Prey · Seasonal · Diet overlap · Forage fish · Gulf of Alaska · Theragra chalcogramma · Ammodytes hexapterus Full text in pdf format Supplementary appendix PreviousNextCite this article as: McKenzie J, Wynne KM (2008) Spatial and temporal variation in the diet of Steller sea lions in the Kodiak Archipelago, 1999 to 2005. Mar Ecol Prog Ser 360:265-283. https://doi.org/10.3354/meps07383Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 360. Online publication date: May 22, 2008 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2008 Inter-Research.