Changing distribution of flocking sea ducks as non-regenerating food resources are depleted
Sutherland & Anderson (1993; J Theor Biol 160:223–230) considered how the distribution of consumers should change as prey resources fixed at the start of a period of exploitation are depleted by foraging activities. Their model predicts that consumers initially aggregate on a single or a few pat...
Published in: | Marine Ecology Progress Series |
---|---|
Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2013
|
Subjects: | |
Online Access: | https://research.wur.nl/en/publications/changing-distribution-of-flocking-sea-ducks-as-non-regenerating-f https://doi.org/10.3354/meps10339 |
id |
ftunivwagenin:oai:library.wur.nl:wurpubs/443933 |
---|---|
record_format |
openpolar |
spelling |
ftunivwagenin:oai:library.wur.nl:wurpubs/443933 2024-02-04T10:00:59+01:00 Changing distribution of flocking sea ducks as non-regenerating food resources are depleted Bustnes, J.O. Systad, G.H. Ydenberg, R.C. 2013 application/pdf https://research.wur.nl/en/publications/changing-distribution-of-flocking-sea-ducks-as-non-regenerating-f https://doi.org/10.3354/meps10339 en eng https://edepot.wur.nl/280007 https://research.wur.nl/en/publications/changing-distribution-of-flocking-sea-ducks-as-non-regenerating-f doi:10.3354/meps10339 info:eu-repo/semantics/restrictedAccess Wageningen University & Research Marine Ecology Progress Series 484 (2013) ISSN: 0171-8630 eagle haliaeetus-albicilla eiders somateria-mollissima habitat selection mytilus-edulis northern norway polysticta-stelleri prey depletion size surf scoters wintering common-eiders info:eu-repo/semantics/article Article/Letter to editor info:eu-repo/semantics/publishedVersion 2013 ftunivwagenin https://doi.org/10.3354/meps10339 2024-01-10T23:20:42Z Sutherland & Anderson (1993; J Theor Biol 160:223–230) considered how the distribution of consumers should change as prey resources fixed at the start of a period of exploitation are depleted by foraging activities. Their model predicts that consumers initially aggregate on a single or a few patches offering the highest feeding rate. As the prey density in those patches is reduced, the feeding rate declines to the level attainable at the next best patches, which are then also exploited. Therefore, an increase in the number of flocks and a decline in flock size should be observed as individuals spread out over the available feeding opportunities. Further, once occupied, a patch is exploited for the remainder of the winter. We tested these predictions with winter survey data on the number, size and location of flocks of common eiders Somateria mollissima and king eiders S. spectabilis wintering in Kvalsundet, a sound in northern Norway. Both species are benthivorous, and there is little or no growth or recruitment of their prey in winter at high-latitude sites. The green sea urchin Strongylocentrotus droebachiensis was the dominant prey of both species in Kvalsundet, and the density of this prey species declined over the winter in kelp beds, the preferred winter habitat of common eiders. Our data showed that both common and king eiders began their winter periods in Kvalsundet aggregated into a few large flocks. As the winter progressed, the distribution changed and birds gathered into more and smaller flocks. In the case of common eiders, flock locations remained fixed once a foraging location began to be exploited. King eiders formed a few large flocks early in the season which drifted in heavy tidal currents, but when these split up into smaller flocks in February, they started to exploit fixed locations. We interpret these results as consistent with the Sutherland & Anderson model. Article in Journal/Newspaper Haliaeetus albicilla Kvalsundet Northern Norway Polysticta stelleri Somateria mollissima Wageningen UR (University & Research Centre): Digital Library Norway Sutherland ENVELOPE(168.467,168.467,-77.500,-77.500) Marine Ecology Progress Series 484 249 257 |
institution |
Open Polar |
collection |
Wageningen UR (University & Research Centre): Digital Library |
op_collection_id |
ftunivwagenin |
language |
English |
topic |
eagle haliaeetus-albicilla eiders somateria-mollissima habitat selection mytilus-edulis northern norway polysticta-stelleri prey depletion size surf scoters wintering common-eiders |
spellingShingle |
eagle haliaeetus-albicilla eiders somateria-mollissima habitat selection mytilus-edulis northern norway polysticta-stelleri prey depletion size surf scoters wintering common-eiders Bustnes, J.O. Systad, G.H. Ydenberg, R.C. Changing distribution of flocking sea ducks as non-regenerating food resources are depleted |
topic_facet |
eagle haliaeetus-albicilla eiders somateria-mollissima habitat selection mytilus-edulis northern norway polysticta-stelleri prey depletion size surf scoters wintering common-eiders |
description |
Sutherland & Anderson (1993; J Theor Biol 160:223–230) considered how the distribution of consumers should change as prey resources fixed at the start of a period of exploitation are depleted by foraging activities. Their model predicts that consumers initially aggregate on a single or a few patches offering the highest feeding rate. As the prey density in those patches is reduced, the feeding rate declines to the level attainable at the next best patches, which are then also exploited. Therefore, an increase in the number of flocks and a decline in flock size should be observed as individuals spread out over the available feeding opportunities. Further, once occupied, a patch is exploited for the remainder of the winter. We tested these predictions with winter survey data on the number, size and location of flocks of common eiders Somateria mollissima and king eiders S. spectabilis wintering in Kvalsundet, a sound in northern Norway. Both species are benthivorous, and there is little or no growth or recruitment of their prey in winter at high-latitude sites. The green sea urchin Strongylocentrotus droebachiensis was the dominant prey of both species in Kvalsundet, and the density of this prey species declined over the winter in kelp beds, the preferred winter habitat of common eiders. Our data showed that both common and king eiders began their winter periods in Kvalsundet aggregated into a few large flocks. As the winter progressed, the distribution changed and birds gathered into more and smaller flocks. In the case of common eiders, flock locations remained fixed once a foraging location began to be exploited. King eiders formed a few large flocks early in the season which drifted in heavy tidal currents, but when these split up into smaller flocks in February, they started to exploit fixed locations. We interpret these results as consistent with the Sutherland & Anderson model. |
format |
Article in Journal/Newspaper |
author |
Bustnes, J.O. Systad, G.H. Ydenberg, R.C. |
author_facet |
Bustnes, J.O. Systad, G.H. Ydenberg, R.C. |
author_sort |
Bustnes, J.O. |
title |
Changing distribution of flocking sea ducks as non-regenerating food resources are depleted |
title_short |
Changing distribution of flocking sea ducks as non-regenerating food resources are depleted |
title_full |
Changing distribution of flocking sea ducks as non-regenerating food resources are depleted |
title_fullStr |
Changing distribution of flocking sea ducks as non-regenerating food resources are depleted |
title_full_unstemmed |
Changing distribution of flocking sea ducks as non-regenerating food resources are depleted |
title_sort |
changing distribution of flocking sea ducks as non-regenerating food resources are depleted |
publishDate |
2013 |
url |
https://research.wur.nl/en/publications/changing-distribution-of-flocking-sea-ducks-as-non-regenerating-f https://doi.org/10.3354/meps10339 |
long_lat |
ENVELOPE(168.467,168.467,-77.500,-77.500) |
geographic |
Norway Sutherland |
geographic_facet |
Norway Sutherland |
genre |
Haliaeetus albicilla Kvalsundet Northern Norway Polysticta stelleri Somateria mollissima |
genre_facet |
Haliaeetus albicilla Kvalsundet Northern Norway Polysticta stelleri Somateria mollissima |
op_source |
Marine Ecology Progress Series 484 (2013) ISSN: 0171-8630 |
op_relation |
https://edepot.wur.nl/280007 https://research.wur.nl/en/publications/changing-distribution-of-flocking-sea-ducks-as-non-regenerating-f doi:10.3354/meps10339 |
op_rights |
info:eu-repo/semantics/restrictedAccess Wageningen University & Research |
op_doi |
https://doi.org/10.3354/meps10339 |
container_title |
Marine Ecology Progress Series |
container_volume |
484 |
container_start_page |
249 |
op_container_end_page |
257 |
_version_ |
1789966570778263552 |