CALORIC CONTENT OF BERING AND CHUKCHI SEA BENTHIC INVERTEBRATES

Abstract

Extensive seasonal sea ice reduction has highlighted the need to evaluate the status and potential long term changes of highly productive benthic communities in the Pacific Arctic Region. Walrus that use sea ice to access offshore feeding areas are now being forced to haul out on land for part of the year, requiring them to forage for benthic prey from closer to shore. To explore this energetic problem, I conducted a caloric survey of benthic invertebrates, and evaluated relationships between caloric content and environmental variables. Latitude was the strongest non-taxonomic dependency for caloric content (ANOVA p=0.003 with taxon dependencies, p<0.001 without). Cluster analysis revealed caloric densities were higher in offshore, high nutrient Bering Sea Anadyr Water, and lower in nearshore, low nutrient Alaska Coastal Water. An evaluation of preservation techniques indicated formalin fixation increased infaunal caloric content (p<0.001), suggesting caution while converting traditional benthic population studies to caloric values.