Selection of avian prey by breeding Sparrowhawks Accipiter nisus in southern Norway: The importance of size and foraging behaviour of prey
Prey selection of the Sparrowhawk (Accipiter nisus) was studied in northern Finland during 1982-1993. A total of 540 prey items (all birds) were recorded from the surroundings of 12 nests. For each prey species a vulnerability index was calculated as the ratio between its proportion in the Sparrowha...
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BirdLife Finland
1993
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fttsvojs:oai:journal.fi:article/133376 2023-09-05T13:21:56+02:00 Selection of avian prey by breeding Sparrowhawks Accipiter nisus in southern Norway: The importance of size and foraging behaviour of prey Selås, V. 1993-09-30 application/pdf https://ornisfennica.journal.fi/article/view/133376 eng eng BirdLife Finland https://ornisfennica.journal.fi/article/view/133376/81922 https://ornisfennica.journal.fi/article/view/133376 Ornis Fennica; Vol 70 Nro 3 (1993); 144–154 Ornis Fennica; Vol. 70 No. 3 (1993); 144–154 0030-5685 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Peer-reviewed Article 1993 fttsvojs 2023-08-23T23:02:42Z Prey selection of the Sparrowhawk (Accipiter nisus) was studied in northern Finland during 1982-1993. A total of 540 prey items (all birds) were recorded from the surroundings of 12 nests. For each prey species a vulnerability index was calculated as the ratio between its proportion in the Sparrowhawk's diet and its proportion in the land bird community (data from the whole of the Oulanka National Park, and spruce forests only). The average prey individual weighed 52 g, whereas the average breeding bird weighed 36 g in the spruce forests and 24 gin the whole of the Oulanka National Park area . Prey vulnerability increased with increasing prey body mass. The result could be interpreted in the light of the optimal foraging theory, large prey being the most profitable among the Sparrowhawks' prey-size range. In the whole of Oulanka data, open habitat species were caught relatively more frequently than forest species, and prey vulnerability correlated negatively with prey abundance . Foraging behaviour and the nest site of the prey species were not related to their vulnerability . Phylogenetic analyses revealed a significant correlation between prey vulnerability and plumage brightness, after the effects of body mass and abundance of prey species were controlled for. Higher relative predation risk of bright species give support to the `sexual selection' hypothesis but not to the `unprofitable prey' hypothesis explaining prey vulnerability . Article in Journal/Newspaper Northern Finland Federation of Finnish Learned Societies: Scientific Journals Online Norway Oulanka ENVELOPE(28.986,28.986,66.455,66.455) |
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Open Polar |
collection |
Federation of Finnish Learned Societies: Scientific Journals Online |
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fttsvojs |
language |
English |
description |
Prey selection of the Sparrowhawk (Accipiter nisus) was studied in northern Finland during 1982-1993. A total of 540 prey items (all birds) were recorded from the surroundings of 12 nests. For each prey species a vulnerability index was calculated as the ratio between its proportion in the Sparrowhawk's diet and its proportion in the land bird community (data from the whole of the Oulanka National Park, and spruce forests only). The average prey individual weighed 52 g, whereas the average breeding bird weighed 36 g in the spruce forests and 24 gin the whole of the Oulanka National Park area . Prey vulnerability increased with increasing prey body mass. The result could be interpreted in the light of the optimal foraging theory, large prey being the most profitable among the Sparrowhawks' prey-size range. In the whole of Oulanka data, open habitat species were caught relatively more frequently than forest species, and prey vulnerability correlated negatively with prey abundance . Foraging behaviour and the nest site of the prey species were not related to their vulnerability . Phylogenetic analyses revealed a significant correlation between prey vulnerability and plumage brightness, after the effects of body mass and abundance of prey species were controlled for. Higher relative predation risk of bright species give support to the `sexual selection' hypothesis but not to the `unprofitable prey' hypothesis explaining prey vulnerability . |
format |
Article in Journal/Newspaper |
author |
Selås, V. |
spellingShingle |
Selås, V. Selection of avian prey by breeding Sparrowhawks Accipiter nisus in southern Norway: The importance of size and foraging behaviour of prey |
author_facet |
Selås, V. |
author_sort |
Selås, V. |
title |
Selection of avian prey by breeding Sparrowhawks Accipiter nisus in southern Norway: The importance of size and foraging behaviour of prey |
title_short |
Selection of avian prey by breeding Sparrowhawks Accipiter nisus in southern Norway: The importance of size and foraging behaviour of prey |
title_full |
Selection of avian prey by breeding Sparrowhawks Accipiter nisus in southern Norway: The importance of size and foraging behaviour of prey |
title_fullStr |
Selection of avian prey by breeding Sparrowhawks Accipiter nisus in southern Norway: The importance of size and foraging behaviour of prey |
title_full_unstemmed |
Selection of avian prey by breeding Sparrowhawks Accipiter nisus in southern Norway: The importance of size and foraging behaviour of prey |
title_sort |
selection of avian prey by breeding sparrowhawks accipiter nisus in southern norway: the importance of size and foraging behaviour of prey |
publisher |
BirdLife Finland |
publishDate |
1993 |
url |
https://ornisfennica.journal.fi/article/view/133376 |
long_lat |
ENVELOPE(28.986,28.986,66.455,66.455) |
geographic |
Norway Oulanka |
geographic_facet |
Norway Oulanka |
genre |
Northern Finland |
genre_facet |
Northern Finland |
op_source |
Ornis Fennica; Vol 70 Nro 3 (1993); 144–154 Ornis Fennica; Vol. 70 No. 3 (1993); 144–154 0030-5685 |
op_relation |
https://ornisfennica.journal.fi/article/view/133376/81922 https://ornisfennica.journal.fi/article/view/133376 |
_version_ |
1776202485856206848 |