DNA metabarcoding of feces to infer summer diet of Pacific walruses

Marine Mammal Science
By: , and 



Environmental conditions in the Chukchi Sea are changing rapidly and may alter the abundance and distribution of marine species and their benthic prey. We used a metabarcoding approach to identify potentially important prey taxa from Pacific walrus (Odobenus rosmarus divergens) fecal samples (n = 87). Bivalvia was the most dominant class of prey (66% of all normalized counts) and occurred in 98% of the samples. Polychaeta and Gastropoda occurred in 70% and 62% of the samples, respectively. The remaining nine invertebrate classes comprised <21% of all normalized counts. The common occurrence of these three prey classes is consistent with examinations of walrus stomach contents. Despite these consistencies, biases in the metabarcoding approach to determine diet from feces have been highlighted in other studies and require further study, in addition to biases that may have arisen from our opportunistic sampling. However, this noninvasive approach provides accurate identification of prey taxa from degraded samples and could yield much‐needed information on shifts in walrus diet in a rapidly changing Arctic.

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Publication type Article
Publication Subtype Journal Article
Title DNA metabarcoding of feces to infer summer diet of Pacific walruses
Series title Marine Mammal Science
DOI 10.1111/mms.12717
Volume 36
Issue 4
Year Published 2020
Language English
Publisher Wiley
Contributing office(s) Alaska Science Center Biology WTEB
Description 6 p.
First page 1196
Last page 1211
Country United States
State Alaska
Other Geospatial Bering Sea, Chukchi Sea
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