Variability In Population Trends, Life History Characteristics, and Milk Composition Of Northern Fur Seals In Alaska
Thesis (M.S.) University of Alaska Fairbanks, 2012 The northern fur seal population on the Pribilof Islands has been declining since the 1960s and is now less than 30% of its former size. Chapter 1 examines factors that might cause a population to decrease to such an extent and concludes that only n...
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ftunivalaska:oai:scholarworks.alaska.edu:11122/8586 2023-05-15T18:48:46+02:00 Variability In Population Trends, Life History Characteristics, and Milk Composition Of Northern Fur Seals In Alaska Hayden, Alison Banks Springer, Alan Iverson, Sara Castellini, Michael 2012 http://hdl.handle.net/11122/8586 unknown http://hdl.handle.net/11122/8586 Program in Marine Science and Limnology Ecology Evolution & development Thesis ms 2012 ftunivalaska 2023-02-23T21:37:05Z Thesis (M.S.) University of Alaska Fairbanks, 2012 The northern fur seal population on the Pribilof Islands has been declining since the 1960s and is now less than 30% of its former size. Chapter 1 examines factors that might cause a population to decrease to such an extent and concludes that only nutritional limitation caused by climate change or commercial fisheries, predation by killer whales, or a combination of factors that includes conditions in the North Pacific during the winter were possible explanations. Chapter 2 reports the seasonal patterns in proximate composition of fur seal milk between St. Paul Island (one of the Pribilof Islands) and Bogoslof Island (an increasing population) to understand the energy requirements of lactation and the energetics of pup growth and body condition at weaning. Factors that caused variability in milk composition included days postpartum, time ashore, individual phenotype, island and preceding trip duration. Average milk lipid increased from 45.5+/-0.7% to 53.8+/-1.0% at St. Paul and from 45.8+/-0.7% to 57.3+/-0.8% at Bogoslof between July and October, while average milk protein remained relatively stable ranging between 10.0% and 10.5%. The lipid content of northern fur seal milk near peak lactation is the highest reported among otariid seals and among the highest known for all mammals. Thesis Alaska Northern fur seal University of Alaska: ScholarWorks@UA Fairbanks Pacific |
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Open Polar |
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University of Alaska: ScholarWorks@UA |
op_collection_id |
ftunivalaska |
language |
unknown |
topic |
Ecology Evolution & development |
spellingShingle |
Ecology Evolution & development Hayden, Alison Banks Variability In Population Trends, Life History Characteristics, and Milk Composition Of Northern Fur Seals In Alaska |
topic_facet |
Ecology Evolution & development |
description |
Thesis (M.S.) University of Alaska Fairbanks, 2012 The northern fur seal population on the Pribilof Islands has been declining since the 1960s and is now less than 30% of its former size. Chapter 1 examines factors that might cause a population to decrease to such an extent and concludes that only nutritional limitation caused by climate change or commercial fisheries, predation by killer whales, or a combination of factors that includes conditions in the North Pacific during the winter were possible explanations. Chapter 2 reports the seasonal patterns in proximate composition of fur seal milk between St. Paul Island (one of the Pribilof Islands) and Bogoslof Island (an increasing population) to understand the energy requirements of lactation and the energetics of pup growth and body condition at weaning. Factors that caused variability in milk composition included days postpartum, time ashore, individual phenotype, island and preceding trip duration. Average milk lipid increased from 45.5+/-0.7% to 53.8+/-1.0% at St. Paul and from 45.8+/-0.7% to 57.3+/-0.8% at Bogoslof between July and October, while average milk protein remained relatively stable ranging between 10.0% and 10.5%. The lipid content of northern fur seal milk near peak lactation is the highest reported among otariid seals and among the highest known for all mammals. |
author2 |
Springer, Alan Iverson, Sara Castellini, Michael |
format |
Thesis |
author |
Hayden, Alison Banks |
author_facet |
Hayden, Alison Banks |
author_sort |
Hayden, Alison Banks |
title |
Variability In Population Trends, Life History Characteristics, and Milk Composition Of Northern Fur Seals In Alaska |
title_short |
Variability In Population Trends, Life History Characteristics, and Milk Composition Of Northern Fur Seals In Alaska |
title_full |
Variability In Population Trends, Life History Characteristics, and Milk Composition Of Northern Fur Seals In Alaska |
title_fullStr |
Variability In Population Trends, Life History Characteristics, and Milk Composition Of Northern Fur Seals In Alaska |
title_full_unstemmed |
Variability In Population Trends, Life History Characteristics, and Milk Composition Of Northern Fur Seals In Alaska |
title_sort |
variability in population trends, life history characteristics, and milk composition of northern fur seals in alaska |
publishDate |
2012 |
url |
http://hdl.handle.net/11122/8586 |
geographic |
Fairbanks Pacific |
geographic_facet |
Fairbanks Pacific |
genre |
Alaska Northern fur seal |
genre_facet |
Alaska Northern fur seal |
op_relation |
http://hdl.handle.net/11122/8586 Program in Marine Science and Limnology |
_version_ |
1766242051032088576 |