Insight into the diet history of ice seals using isotopic signatures of muscle tissue and claws
Thesis (M.S.) University of Alaska Fairbanks, 2012 Climate change and sea ice reduction in the Arctic may impact foraging of ice-associated predators. The goal of my thesis work was to examine interannual differences in the diet of ringed, bearded, spotted, and ribbon seals as described by stable ni...
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ftunivalaska:oai:scholarworks.alaska.edu:11122/8440 2023-05-15T14:54:51+02:00 Insight into the diet history of ice seals using isotopic signatures of muscle tissue and claws Carroll, Sara Shanae Norcross, Brenda Horstmann-Dehn, Larissa Quakenbush, Lori Wooller, Matthew 2012-05 http://hdl.handle.net/11122/8440 en_US eng http://hdl.handle.net/11122/8440 Program in Marine Science and Limnology Ringed seal Food Arctic regions Bearded seal Phoca largha Ribbon seal Thesis ms 2012 ftunivalaska 2023-02-23T21:37:02Z Thesis (M.S.) University of Alaska Fairbanks, 2012 Climate change and sea ice reduction in the Arctic may impact foraging of ice-associated predators. The goal of my thesis work was to examine interannual differences in the diet of ringed, bearded, spotted, and ribbon seals as described by stable nitrogen and carbon isotope ratios of muscle tissue and claws to assess foraging plasticity. Isotopic mixing models from muscle data were used to describe the proportional contribution of prey groups during 2003, 2008-2010. Results showed a higher proportional contribution of smelt (Osmeridae) and benthic prey to ringed and bearded seal diets in 2003 compared to 2008-2010. Seasonal keratin layers deposited in claws can document trophic history up to about 10 years. During 2007 (record ice minimum), proportionally more ringed seals fed at a lower trophic level, while spotted seal adults and young-of-the-year fed at a lower trophic level during 2006. Bearded seals may have been foraging more pelagically from 2008 to 2010. Ice seals may be taking advantage of more abundant pelagic crustaceans as the Arctic ecosystem changes to a pelagic-dominated food web. Interannual variations and high variability among species and individual diets illustrate the opportunistic nature and flexibility of ice seals to changes in prey composition. 1. General introduction -- 2. Interannual variations in the diet of ice seals assessed by isotopic mixing models -- 3. Diet history of ice seals using stable isotope ratios in claw growth bands -- 4. General discussion. Thesis Arctic bearded seal Climate change ringed seal Sea ice Alaska University of Alaska: ScholarWorks@UA Arctic Fairbanks |
institution |
Open Polar |
collection |
University of Alaska: ScholarWorks@UA |
op_collection_id |
ftunivalaska |
language |
English |
topic |
Ringed seal Food Arctic regions Bearded seal Phoca largha Ribbon seal |
spellingShingle |
Ringed seal Food Arctic regions Bearded seal Phoca largha Ribbon seal Carroll, Sara Shanae Insight into the diet history of ice seals using isotopic signatures of muscle tissue and claws |
topic_facet |
Ringed seal Food Arctic regions Bearded seal Phoca largha Ribbon seal |
description |
Thesis (M.S.) University of Alaska Fairbanks, 2012 Climate change and sea ice reduction in the Arctic may impact foraging of ice-associated predators. The goal of my thesis work was to examine interannual differences in the diet of ringed, bearded, spotted, and ribbon seals as described by stable nitrogen and carbon isotope ratios of muscle tissue and claws to assess foraging plasticity. Isotopic mixing models from muscle data were used to describe the proportional contribution of prey groups during 2003, 2008-2010. Results showed a higher proportional contribution of smelt (Osmeridae) and benthic prey to ringed and bearded seal diets in 2003 compared to 2008-2010. Seasonal keratin layers deposited in claws can document trophic history up to about 10 years. During 2007 (record ice minimum), proportionally more ringed seals fed at a lower trophic level, while spotted seal adults and young-of-the-year fed at a lower trophic level during 2006. Bearded seals may have been foraging more pelagically from 2008 to 2010. Ice seals may be taking advantage of more abundant pelagic crustaceans as the Arctic ecosystem changes to a pelagic-dominated food web. Interannual variations and high variability among species and individual diets illustrate the opportunistic nature and flexibility of ice seals to changes in prey composition. 1. General introduction -- 2. Interannual variations in the diet of ice seals assessed by isotopic mixing models -- 3. Diet history of ice seals using stable isotope ratios in claw growth bands -- 4. General discussion. |
author2 |
Norcross, Brenda Horstmann-Dehn, Larissa Quakenbush, Lori Wooller, Matthew |
format |
Thesis |
author |
Carroll, Sara Shanae |
author_facet |
Carroll, Sara Shanae |
author_sort |
Carroll, Sara Shanae |
title |
Insight into the diet history of ice seals using isotopic signatures of muscle tissue and claws |
title_short |
Insight into the diet history of ice seals using isotopic signatures of muscle tissue and claws |
title_full |
Insight into the diet history of ice seals using isotopic signatures of muscle tissue and claws |
title_fullStr |
Insight into the diet history of ice seals using isotopic signatures of muscle tissue and claws |
title_full_unstemmed |
Insight into the diet history of ice seals using isotopic signatures of muscle tissue and claws |
title_sort |
insight into the diet history of ice seals using isotopic signatures of muscle tissue and claws |
publishDate |
2012 |
url |
http://hdl.handle.net/11122/8440 |
geographic |
Arctic Fairbanks |
geographic_facet |
Arctic Fairbanks |
genre |
Arctic bearded seal Climate change ringed seal Sea ice Alaska |
genre_facet |
Arctic bearded seal Climate change ringed seal Sea ice Alaska |
op_relation |
http://hdl.handle.net/11122/8440 Program in Marine Science and Limnology |
_version_ |
1766326607238135808 |