Species Composition and Abundance of Juvenile Groundfishes Around Steller Sea Lion Eumetopias jubatus Rookeries in the Gulf of Alaska
Mueter FJ and Norcross BL. 2000. Species Composition and Abundance of Juvenile Groundfishes Around Steller Sea Lion Eumetopias jubatus Rookeries in the Gulf of Alaska. Alaska Fishery Research Bulletin. 7:32-43
We conducted bottom trawl surveys to determine species composition and abundance of juvenile groundfish communities around 6 Steller sea lion rookeries in the western Gulf of Alaska from 1994 to 1996. Overall, the most abundant species in our collections were rock sole Pleuronectes bilineatus, walleye pollock Theragra chalcogramma, Pacific halibut Hippoglossus stenolepis, northern sculpin Icelinus borealis, Triglops spp., Gymnocanthus spp., Pacific cod Gadus macrocephalus, slim sculpin Radulinus asprellus, and arrowtooth flounder Atheresthes stomias. Our results showed significant differences in species composition among rookeries within each of 3 depth strata and a greater abundance of juvenile groundfishes in the western part of the study area. Gadid and flatfish species were more abundant and had a higher probability of occurrence in the vicinity of sea lion rookeries on Akun, Ugamak, Atkins, and Chowiet Islands, compared to rookeries on Marmot and Sugarloaf Islands. The observed differences in species composition coincided with differences in topography, substrate composition, temperature, and salinity. A potential relationship between the abundance of juvenile groundfishes and sea lion survival is discussed.
- Type
- Journal Article
- Authors
- Mueter, F; Norcross, B
- Units
- GLBA , SITK
- Keywords
- Coastal/Marine Systems, Fisheries Management, Forage Fish, Groundfish, Gulf Of Alaska, Marine Ecology, Marine Mammal, population decline (sea lion), Population Declines, prey abundance (sea lion), sea lion