Sexual differences in the foraging ecology of 19th century beluga whales ( Delphinapterus leucas) from the Canadian High Arctic

• Published in: Marine Mammal Science
• Main Authors: Szpak, Paul, Julien, Marie‐Hélène, Royle, Thomas C. A., Savelle, James M., Yang, Dongya Y., Richards, Michael P.
• Other Authors: Canada Foundation for Innovation, Canada Research Chairs, Natural Sciences and Engineering Research Council of Canada, Social Sciences and Humanities Research Council of Canada
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2019
• Subjects: Arctic cod; Beluga; Beluga*; Delphinapterus leucas
• Online Access: http://dx.doi.org/10.1111/mms.12655; https://onlinelibrary.wiley.com/doi/pdf/10.1111/mms.12655; https://onlinelibrary.wiley.com/doi/full-xml/10.1111/mms.12655

Abstract Marine mammals often exhibit significant sexual segregation in their diet and habitat use but these differences have not been studied systematically in historic or ancient populations due to the difficulties associated with determining the sex of skeletal elements based on gross morphology. Using a combined ancient DNA and stable isotope approach, we document a sexual difference in the foraging ecology of late 19th century beluga whales ( Delphinapterus leucas ) from the Canadian High Arctic. Using two PCR assays that coamplify fragments of the Y‐linked SRY and X‐linked ZFX genes, we assigned reproducible sex identities to 35 beluga specimens. This provided a basis for investigating sex‐specific differences in foraging ecology using stable carbon and nitrogen isotope analyses of bone collagen. These isotopic data demonstrate that although both males and females primarily consumed Arctic cod, males utilized a wider range of prey than females, feeding on high trophic level benthic prey (sculpins) to a greater extent. Because bone collagen integrates prey isotopic compositions over the course of several years these sex‐based differences in beluga bone collagen isotopic compositions reflect long‐term and sustained sexual differences in foraging.