The behavioral basis for nonlinear functional responses and optimal foraging in Antarctic fur seals.
This study investigated the degree to which the behavior of a predator in the marine environment can be used to indicate the availability of prey. It examined this in Antarctic fur seals (Arctocephalus gazella) feeding on krill, with a view to understanding how behavioral choices could lead to a non...
Published in: | Ecology |
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Language: | English |
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Online Access: | https://risweb.st-andrews.ac.uk/portal/en/researchoutput/the-behavioral-basis-for-nonlinear-functional-responses-and-optimal-foraging-in-antarctic-fur-seals(2a525b2e-b671-4111-983f-767c5801ab40).html https://doi.org/10.1890/03-4005 http://www.scopus.com/inward/record.url?scp=1542319706&partnerID=8YFLogxK |
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ftunstandrewcris:oai:risweb.st-andrews.ac.uk:publications/2a525b2e-b671-4111-983f-767c5801ab40 2023-05-15T13:47:48+02:00 The behavioral basis for nonlinear functional responses and optimal foraging in Antarctic fur seals. Mori, Y Boyd, Ian Lamont 2004-02 https://risweb.st-andrews.ac.uk/portal/en/researchoutput/the-behavioral-basis-for-nonlinear-functional-responses-and-optimal-foraging-in-antarctic-fur-seals(2a525b2e-b671-4111-983f-767c5801ab40).html https://doi.org/10.1890/03-4005 http://www.scopus.com/inward/record.url?scp=1542319706&partnerID=8YFLogxK eng eng info:eu-repo/semantics/restrictedAccess Mori , Y & Boyd , I L 2004 , ' The behavioral basis for nonlinear functional responses and optimal foraging in Antarctic fur seals. ' , Ecology , vol. 85 , no. 2 , pp. 398 - 410 . https://doi.org/10.1890/03-4005 Antarctic fur seals Arctocephalus gazella behavioral index food availability functional response optimal foraging patch use rate maximization South Georgia MARGINAL VALUE THEOREM EUPHAUSIA-SUPERBA INTERANNUAL VARIABILITY MARINE PREDATORS TEMPORAL SCALE TIME KRILL ABUNDANCE article 2004 ftunstandrewcris https://doi.org/10.1890/03-4005 2021-12-26T14:12:56Z This study investigated the degree to which the behavior of a predator in the marine environment can be used to indicate the availability of prey. It examined this in Antarctic fur seals (Arctocephalus gazella) feeding on krill, with a view to understanding how behavioral choices could lead to a nonlinear functional response. The study showed how fur seals adjusted their time budgets to maximize the mean rate of energy intake in response to varying prey abundance. The behavioral indicator of prey abundance was the amount of time spent by fur seals at the bottom of dives after adjustment for dive depth. This indicator was well correlated with independent measures of prey abundance. The indicator was calibrated in terms of net rate of energy intake from information about energy expenditures in Antarctic fur seals and was used within the framework of optimal foraging theory to examine how female fur seals organized their foraging activity within and between bouts. Foraging in Antarctic fur seals conformed to many of the predictions from energy rate-maximizing behavior. For example, the apparent net rate of energy intake by fur seals declined with time spent in a patch, and the rate of energy intake on leaving a patch declined as apparent food availability in the environment declined. In addition, the time spent in patches increased as apparent food availability declined. Antarctic fur seals were able to adjust their behavior to track highly variable prey distributions and densities. The simple decision about when to leave a patch in relation to current environmental prey availability appears to be responsible for allowing fur seals to maintain saturation of the foraging rate as food density declines. Article in Journal/Newspaper Antarc* Antarctic Antarctic Fur Seals Arctocephalus gazella Euphausia superba University of St Andrews: Research Portal Antarctic Ecology 85 2 398 410 |
institution |
Open Polar |
collection |
University of St Andrews: Research Portal |
op_collection_id |
ftunstandrewcris |
language |
English |
topic |
Antarctic fur seals Arctocephalus gazella behavioral index food availability functional response optimal foraging patch use rate maximization South Georgia MARGINAL VALUE THEOREM EUPHAUSIA-SUPERBA INTERANNUAL VARIABILITY MARINE PREDATORS TEMPORAL SCALE TIME KRILL ABUNDANCE |
spellingShingle |
Antarctic fur seals Arctocephalus gazella behavioral index food availability functional response optimal foraging patch use rate maximization South Georgia MARGINAL VALUE THEOREM EUPHAUSIA-SUPERBA INTERANNUAL VARIABILITY MARINE PREDATORS TEMPORAL SCALE TIME KRILL ABUNDANCE Mori, Y Boyd, Ian Lamont The behavioral basis for nonlinear functional responses and optimal foraging in Antarctic fur seals. |
topic_facet |
Antarctic fur seals Arctocephalus gazella behavioral index food availability functional response optimal foraging patch use rate maximization South Georgia MARGINAL VALUE THEOREM EUPHAUSIA-SUPERBA INTERANNUAL VARIABILITY MARINE PREDATORS TEMPORAL SCALE TIME KRILL ABUNDANCE |
description |
This study investigated the degree to which the behavior of a predator in the marine environment can be used to indicate the availability of prey. It examined this in Antarctic fur seals (Arctocephalus gazella) feeding on krill, with a view to understanding how behavioral choices could lead to a nonlinear functional response. The study showed how fur seals adjusted their time budgets to maximize the mean rate of energy intake in response to varying prey abundance. The behavioral indicator of prey abundance was the amount of time spent by fur seals at the bottom of dives after adjustment for dive depth. This indicator was well correlated with independent measures of prey abundance. The indicator was calibrated in terms of net rate of energy intake from information about energy expenditures in Antarctic fur seals and was used within the framework of optimal foraging theory to examine how female fur seals organized their foraging activity within and between bouts. Foraging in Antarctic fur seals conformed to many of the predictions from energy rate-maximizing behavior. For example, the apparent net rate of energy intake by fur seals declined with time spent in a patch, and the rate of energy intake on leaving a patch declined as apparent food availability in the environment declined. In addition, the time spent in patches increased as apparent food availability declined. Antarctic fur seals were able to adjust their behavior to track highly variable prey distributions and densities. The simple decision about when to leave a patch in relation to current environmental prey availability appears to be responsible for allowing fur seals to maintain saturation of the foraging rate as food density declines. |
format |
Article in Journal/Newspaper |
author |
Mori, Y Boyd, Ian Lamont |
author_facet |
Mori, Y Boyd, Ian Lamont |
author_sort |
Mori, Y |
title |
The behavioral basis for nonlinear functional responses and optimal foraging in Antarctic fur seals. |
title_short |
The behavioral basis for nonlinear functional responses and optimal foraging in Antarctic fur seals. |
title_full |
The behavioral basis for nonlinear functional responses and optimal foraging in Antarctic fur seals. |
title_fullStr |
The behavioral basis for nonlinear functional responses and optimal foraging in Antarctic fur seals. |
title_full_unstemmed |
The behavioral basis for nonlinear functional responses and optimal foraging in Antarctic fur seals. |
title_sort |
behavioral basis for nonlinear functional responses and optimal foraging in antarctic fur seals. |
publishDate |
2004 |
url |
https://risweb.st-andrews.ac.uk/portal/en/researchoutput/the-behavioral-basis-for-nonlinear-functional-responses-and-optimal-foraging-in-antarctic-fur-seals(2a525b2e-b671-4111-983f-767c5801ab40).html https://doi.org/10.1890/03-4005 http://www.scopus.com/inward/record.url?scp=1542319706&partnerID=8YFLogxK |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic Antarctic Fur Seals Arctocephalus gazella Euphausia superba |
genre_facet |
Antarc* Antarctic Antarctic Fur Seals Arctocephalus gazella Euphausia superba |
op_source |
Mori , Y & Boyd , I L 2004 , ' The behavioral basis for nonlinear functional responses and optimal foraging in Antarctic fur seals. ' , Ecology , vol. 85 , no. 2 , pp. 398 - 410 . https://doi.org/10.1890/03-4005 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1890/03-4005 |
container_title |
Ecology |
container_volume |
85 |
container_issue |
2 |
container_start_page |
398 |
op_container_end_page |
410 |
_version_ |
1766247896047419392 |