POPULATION OF THE MACARONI PENGUIN EUDYPTES CHRYSOLOPHUS AT MARION ISLAND, 1994/95–2002/03, WITH INFORMATION ON BREEDING AND DIET
There is indication that numbers of macaroni penguins Eudyptes chrysolophus at subantarctic Marion Island have decreased since the early 1980s. Estimates of the population at the island fell from about 405 000 pairs in 1983/84 and 434 000 pairs in 1994/95 to about 356 000 pairs in 2002/03. Two large...
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ftjafricanj:oai:ojs.ajol.info:article/33159 2023-05-15T16:08:22+02:00 POPULATION OF THE MACARONI PENGUIN EUDYPTES CHRYSOLOPHUS AT MARION ISLAND, 1994/95–2002/03, WITH INFORMATION ON BREEDING AND DIET CRAWFORD, R JM COOPER, J. DYER, B M 2005-05-12 application/pdf http://www.ajol.info/index.php/ajms/article/view/33159 eng eng NISC http://www.ajol.info/index.php/ajms/article/view/33159/24151 http://www.ajol.info/index.php/ajms/article/view/33159 Copyright for articles published in this journal is retained by the publisher. African Journal of Marine Science; Vol 25 (2003); 475-486 1814-232X breeding diet Eudyptes chrysolophus macaroni penguin Marion Island population Subantarctic info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Peer-reviewed Article 2005 ftjafricanj 2017-03-05T06:44:53Z There is indication that numbers of macaroni penguins Eudyptes chrysolophus at subantarctic Marion Island have decreased since the early 1980s. Estimates of the population at the island fell from about 405 000 pairs in 1983/84 and 434 000 pairs in 1994/95 to about 356 000 pairs in 2002/03. Two large colonies, at Bullard Beach and Kildalkey Bay, account for about 85% of the overall population. At both these colonies, the area occupied by breeders showed no trend between 1983/84 and 2002/03, but the mean density of nests decreased. However, error on estimates of abundance at these colonies precludes demonstration of a significant decrease in the overall population. Numbers of occupied nests at other colonies decreased from 79 000 in 1994/95 to 31 000 in 2002/03. At three small colonies there was a significant decrease of 88% between 1982/83 and 2002/03. At Marion Island, macaroni penguins usually breed for the first time when aged about three years. From 1994/95 to 2002/03, pairs fledged an average of 0.46 chicks per year, a number considered insufficient to maintain the population. However, during that period there was a significant increase in reproductive success with time. In the same period, the masses of males and females on arrival at breeding colonies were significantly correlated. Both showed a marked decrease in 1998/99, after the El Niño of 1997/98. In most seasons from 1994/95 to 2001/02 crustaceans dominated the food, but the mass of chicks at fledging was significantly related to the contribution of fish to the diet.Afr. J. mar. Sci. 25: 475–486 Article in Journal/Newspaper Eudyptes chrysolophus Macaroni penguin Marion Island AJOL - African Journals Online |
institution |
Open Polar |
collection |
AJOL - African Journals Online |
op_collection_id |
ftjafricanj |
language |
English |
topic |
breeding diet Eudyptes chrysolophus macaroni penguin Marion Island population Subantarctic |
spellingShingle |
breeding diet Eudyptes chrysolophus macaroni penguin Marion Island population Subantarctic CRAWFORD, R JM COOPER, J. DYER, B M POPULATION OF THE MACARONI PENGUIN EUDYPTES CHRYSOLOPHUS AT MARION ISLAND, 1994/95–2002/03, WITH INFORMATION ON BREEDING AND DIET |
topic_facet |
breeding diet Eudyptes chrysolophus macaroni penguin Marion Island population Subantarctic |
description |
There is indication that numbers of macaroni penguins Eudyptes chrysolophus at subantarctic Marion Island have decreased since the early 1980s. Estimates of the population at the island fell from about 405 000 pairs in 1983/84 and 434 000 pairs in 1994/95 to about 356 000 pairs in 2002/03. Two large colonies, at Bullard Beach and Kildalkey Bay, account for about 85% of the overall population. At both these colonies, the area occupied by breeders showed no trend between 1983/84 and 2002/03, but the mean density of nests decreased. However, error on estimates of abundance at these colonies precludes demonstration of a significant decrease in the overall population. Numbers of occupied nests at other colonies decreased from 79 000 in 1994/95 to 31 000 in 2002/03. At three small colonies there was a significant decrease of 88% between 1982/83 and 2002/03. At Marion Island, macaroni penguins usually breed for the first time when aged about three years. From 1994/95 to 2002/03, pairs fledged an average of 0.46 chicks per year, a number considered insufficient to maintain the population. However, during that period there was a significant increase in reproductive success with time. In the same period, the masses of males and females on arrival at breeding colonies were significantly correlated. Both showed a marked decrease in 1998/99, after the El Niño of 1997/98. In most seasons from 1994/95 to 2001/02 crustaceans dominated the food, but the mass of chicks at fledging was significantly related to the contribution of fish to the diet.Afr. J. mar. Sci. 25: 475–486 |
format |
Article in Journal/Newspaper |
author |
CRAWFORD, R JM COOPER, J. DYER, B M |
author_facet |
CRAWFORD, R JM COOPER, J. DYER, B M |
author_sort |
CRAWFORD, R JM |
title |
POPULATION OF THE MACARONI PENGUIN EUDYPTES CHRYSOLOPHUS AT MARION ISLAND, 1994/95–2002/03, WITH INFORMATION ON BREEDING AND DIET |
title_short |
POPULATION OF THE MACARONI PENGUIN EUDYPTES CHRYSOLOPHUS AT MARION ISLAND, 1994/95–2002/03, WITH INFORMATION ON BREEDING AND DIET |
title_full |
POPULATION OF THE MACARONI PENGUIN EUDYPTES CHRYSOLOPHUS AT MARION ISLAND, 1994/95–2002/03, WITH INFORMATION ON BREEDING AND DIET |
title_fullStr |
POPULATION OF THE MACARONI PENGUIN EUDYPTES CHRYSOLOPHUS AT MARION ISLAND, 1994/95–2002/03, WITH INFORMATION ON BREEDING AND DIET |
title_full_unstemmed |
POPULATION OF THE MACARONI PENGUIN EUDYPTES CHRYSOLOPHUS AT MARION ISLAND, 1994/95–2002/03, WITH INFORMATION ON BREEDING AND DIET |
title_sort |
population of the macaroni penguin eudyptes chrysolophus at marion island, 1994/95–2002/03, with information on breeding and diet |
publisher |
NISC |
publishDate |
2005 |
url |
http://www.ajol.info/index.php/ajms/article/view/33159 |
genre |
Eudyptes chrysolophus Macaroni penguin Marion Island |
genre_facet |
Eudyptes chrysolophus Macaroni penguin Marion Island |
op_source |
African Journal of Marine Science; Vol 25 (2003); 475-486 1814-232X |
op_relation |
http://www.ajol.info/index.php/ajms/article/view/33159/24151 http://www.ajol.info/index.php/ajms/article/view/33159 |
op_rights |
Copyright for articles published in this journal is retained by the publisher. |
_version_ |
1766404417874034688 |