Distinct gut microbiomes in two polar bear subpopulations inhabiting different sea ice ecoregions

Scientific Reports
By: , and 

Links

Abstract

Gut microbiomes were analyzed by 16S rRNA gene metabarcoding for polar bears (Ursus maritimus) from the southern Beaufort Sea (SB), where sea ice loss has led to increased use of land-based food resources by bears, and from East Greenland (EG), where persistent sea ice has allowed hunting of ice-associated prey nearly year-round. SB polar bears showed a higher number of total (940 vs. 742) and unique (387 vs. 189) amplicon sequence variants and higher inter-individual variation compared to EG polar bears. Gut microbiome composition differed significantly between the two subpopulations and among sex/age classes, likely driven by diet variation and ontogenetic shifts in the gut microbiome. Dietary tracer analysis using fatty acid signatures for SB polar bears showed that diet explained more intrapopulation variation in gut microbiome composition and diversity than other tested variables, i.e., sex/age class, body condition, and capture year. Substantial differences in the SB gut microbiome relative to EG polar bears, and associations between SB gut microbiome and diet, suggest that the shifting foraging habits of SB polar bears tied to sea ice loss may be altering their gut microbiome, with potential consequences for nutrition and physiology.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Distinct gut microbiomes in two polar bear subpopulations inhabiting different sea ice ecoregions
Series title Scientific Reports
DOI 10.1038/s41598-021-04340-2
Volume 12
Year Published 2022
Language English
Publisher Nature Publications
Contributing office(s) Alaska Science Center Biology MFEB
Description 522, 15 p.
Country Greenland, United States
State Alaska
Google Analytic Metrics Metrics page
Additional publication details