Dietary segregation of krill-eating South Georgia seabirds

The diets of six of the main seabird species (two petrels, two albatrosses, two penguins) breeding at Bird Island, South Georgia were studied simultaneously during the chick-rearing period in 1986. For five species, Antarctic krill Euphausia superba was the main food (39–98% by mass); grey-headed al...

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Published in:Journal of Zoology
Main Authors: Croxall, J. P., Prince, P. A., Reid, K.
Format: Article in Journal/Newspaper
Language:unknown
Published: Zoological Society of London 1997
Subjects:
Online Access:http://nora.nerc.ac.uk/id/eprint/514448/
https://doi.org/10.1111/j.1469-7998.1997.tb03854.x
id ftnerc:oai:nora.nerc.ac.uk:514448
record_format openpolar
spelling ftnerc:oai:nora.nerc.ac.uk:514448 2023-05-15T13:49:33+02:00 Dietary segregation of krill-eating South Georgia seabirds Croxall, J. P. Prince, P. A. Reid, K. 1997-07 http://nora.nerc.ac.uk/id/eprint/514448/ https://doi.org/10.1111/j.1469-7998.1997.tb03854.x unknown Zoological Society of London Croxall, J. P.; Prince, P. A.; Reid, K. 1997 Dietary segregation of krill-eating South Georgia seabirds. Journal of Zoology, 242 (3). 531-556. https://doi.org/10.1111/j.1469-7998.1997.tb03854.x <https://doi.org/10.1111/j.1469-7998.1997.tb03854.x> Publication - Article PeerReviewed 1997 ftnerc https://doi.org/10.1111/j.1469-7998.1997.tb03854.x 2023-02-04T19:43:29Z The diets of six of the main seabird species (two petrels, two albatrosses, two penguins) breeding at Bird Island, South Georgia were studied simultaneously during the chick-rearing period in 1986. For five species, Antarctic krill Euphausia superba was the main food (39–98% by mass); grey-headed albatrosses took mainly the ommastrephid squid Martialia hyadesi (71%) and only 16% krill. The size of the krill taken was similar between seabird species, although there were small but significant differences between penguins and the other species. Sex and reproductive status of krill, however, was different between all seabird species, reflecting some combination of differences in foraging ranges, selectivity by predators, or differences in escape responses of krill. For the krill-eating species, the rest of the diet varied substantially between species, comprising Martialia and nototheniid fish (blackbrowed albatross and, along with lanternfish, white-chinned petrel), lanternfish and amphipods (Antarctic prion and macaroni penguin), and icefish (gentoo penguin). Long-term data on breeding success and information on diet in 5–10 other years suggest that in 1986 seabird diet and reproductive performance was indicative of a year of good availability of krill around South Georgia. In such circumstances, ecological segregation between krill-eating species appears to be maintained chiefly by differences in foraging range and feeding methods, which are reviewed. This situation is rather different from the few studies of seabird communities elsewhere, where prey type and size are believed to be the main mechanisms of dietary segregation Article in Journal/Newspaper Antarc* Antarctic Antarctic Krill Antarctic prion Bird Island Euphausia superba Gentoo penguin Icefish Macaroni penguin Natural Environment Research Council: NERC Open Research Archive Antarctic Bird Island ENVELOPE(-38.060,-38.060,-54.004,-54.004) Journal of Zoology 242 3 531 556
institution Open Polar
collection Natural Environment Research Council: NERC Open Research Archive
op_collection_id ftnerc
language unknown
description The diets of six of the main seabird species (two petrels, two albatrosses, two penguins) breeding at Bird Island, South Georgia were studied simultaneously during the chick-rearing period in 1986. For five species, Antarctic krill Euphausia superba was the main food (39–98% by mass); grey-headed albatrosses took mainly the ommastrephid squid Martialia hyadesi (71%) and only 16% krill. The size of the krill taken was similar between seabird species, although there were small but significant differences between penguins and the other species. Sex and reproductive status of krill, however, was different between all seabird species, reflecting some combination of differences in foraging ranges, selectivity by predators, or differences in escape responses of krill. For the krill-eating species, the rest of the diet varied substantially between species, comprising Martialia and nototheniid fish (blackbrowed albatross and, along with lanternfish, white-chinned petrel), lanternfish and amphipods (Antarctic prion and macaroni penguin), and icefish (gentoo penguin). Long-term data on breeding success and information on diet in 5–10 other years suggest that in 1986 seabird diet and reproductive performance was indicative of a year of good availability of krill around South Georgia. In such circumstances, ecological segregation between krill-eating species appears to be maintained chiefly by differences in foraging range and feeding methods, which are reviewed. This situation is rather different from the few studies of seabird communities elsewhere, where prey type and size are believed to be the main mechanisms of dietary segregation
format Article in Journal/Newspaper
author Croxall, J. P.
Prince, P. A.
Reid, K.
spellingShingle Croxall, J. P.
Prince, P. A.
Reid, K.
Dietary segregation of krill-eating South Georgia seabirds
author_facet Croxall, J. P.
Prince, P. A.
Reid, K.
author_sort Croxall, J. P.
title Dietary segregation of krill-eating South Georgia seabirds
title_short Dietary segregation of krill-eating South Georgia seabirds
title_full Dietary segregation of krill-eating South Georgia seabirds
title_fullStr Dietary segregation of krill-eating South Georgia seabirds
title_full_unstemmed Dietary segregation of krill-eating South Georgia seabirds
title_sort dietary segregation of krill-eating south georgia seabirds
publisher Zoological Society of London
publishDate 1997
url http://nora.nerc.ac.uk/id/eprint/514448/
https://doi.org/10.1111/j.1469-7998.1997.tb03854.x
long_lat ENVELOPE(-38.060,-38.060,-54.004,-54.004)
geographic Antarctic
Bird Island
geographic_facet Antarctic
Bird Island
genre Antarc*
Antarctic
Antarctic Krill
Antarctic prion
Bird Island
Euphausia superba
Gentoo penguin
Icefish
Macaroni penguin
genre_facet Antarc*
Antarctic
Antarctic Krill
Antarctic prion
Bird Island
Euphausia superba
Gentoo penguin
Icefish
Macaroni penguin
op_relation Croxall, J. P.; Prince, P. A.; Reid, K. 1997 Dietary segregation of krill-eating South Georgia seabirds. Journal of Zoology, 242 (3). 531-556. https://doi.org/10.1111/j.1469-7998.1997.tb03854.x <https://doi.org/10.1111/j.1469-7998.1997.tb03854.x>
op_doi https://doi.org/10.1111/j.1469-7998.1997.tb03854.x
container_title Journal of Zoology
container_volume 242
container_issue 3
container_start_page 531
op_container_end_page 556
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