Premium
DNA metabarcoding of feces to infer summer diet of Pacific walruses
Author(s) -
Sonsthagen Sarah A.,
Jay Chadwick V.,
Cornman Robert S.,
Fischbach Anthony S.,
Grebmeier Jacqueline M.,
Talbot Sandra L.
Publication year - 2020
Publication title -
marine mammal science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.723
H-Index - 78
eISSN - 1748-7692
pISSN - 0824-0469
DOI - 10.1111/mms.12717
Subject(s) - predation , biology , invertebrate , benthic zone , feces , taxon , zoology , ecology , abundance (ecology) , gastropoda , mollusca , environmental dna , arctic , biodiversity
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.