Biochemistry, Biophysics, and Structural Biology Commons^™

Latitudinal Variation In Ecological Opportunity And Intraspecific Competition Indicates Differences In Niche Variability And Diet Specialization Of Arctic Marine Predators, David J. Yurkowski, Steven Ferguson, Emily S. Choy, Lisa L. Loseto, Tanya M. Brown, Derek Cg Muir, Christina Ad Semeniuk, Aaron T. Fisk

Great Lakes Institute for Environmental Research Publications

Individual specialization (IS), where individuals within populations irrespective of age, sex, and body size are either specialized or generalized in terms of resource use, has implications on ecological niches and food web structure. Niche size and degree of IS of near-top trophic-level marine predators have been little studied in polar regions or with latitude. We quantified the largescale latitudinal variation of population- and individual-level niche size and IS in ringed seals (Pusa hispida) and beluga whales (Delphinapterus leucas) using stable carbon and nitrogen isotope analysis on 379 paired ringed seal liver and muscle samples and 124 paired beluga skin and …