Effects of duckling body condition on hunting vulnerability in juvenile and immature common eiders Somateria mollissima
Condition related pre‐breeding hunting vulnerability in the common eider Somateria mollissima, i.e. the relationship between body condition attained as a duckling and the probability of being shot, was analysed from recoveries of hunter‐retrieved birds ringed in the Stavns Fjord colony in Denmark du...
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Online Access: | http://dx.doi.org/10.2981/wlb.2001.013 https://onlinelibrary.wiley.com/doi/full-xml/10.2981/wlb.2001.013 https://onlinelibrary.wiley.com/doi/pdf/10.2981/wlb.2001.013 |
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crwiley:10.2981/wlb.2001.013 2024-09-09T19:36:52+00:00 Effects of duckling body condition on hunting vulnerability in juvenile and immature common eiders Somateria mollissima Christensen, Thomas Kjær 2001 http://dx.doi.org/10.2981/wlb.2001.013 https://onlinelibrary.wiley.com/doi/full-xml/10.2981/wlb.2001.013 https://onlinelibrary.wiley.com/doi/pdf/10.2981/wlb.2001.013 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Wildlife Biology volume 7, issue 2, page 97-104 ISSN 1903-220X 1903-220X journal-article 2001 crwiley https://doi.org/10.2981/wlb.2001.013 2024-07-09T04:12:57Z Condition related pre‐breeding hunting vulnerability in the common eider Somateria mollissima, i.e. the relationship between body condition attained as a duckling and the probability of being shot, was analysed from recoveries of hunter‐retrieved birds ringed in the Stavns Fjord colony in Denmark during 1991–1995. Mean duckling cohort condition showed significant variation between years, but the proportions of birds retrieved during the first three seasons were similar (4.9% ± 1.4 SD). The proportion of birds retrieved by hunters declined from 3.9% in the first year to 0.64% and 0.38% in the second and third year, respectively. A condition bias was found in first‐year retrieved birds in the cohorts with the highest and poorest mean condition, but not in the cohorts of intermediate condition. In accordance with a priori predictions regarding condition related non‐hunting mortality during the period between marking and the opening of the hunting season, the direction of the bias was negative (hunters retrieved poor individuals compared to cohort mean) in the cohort of high mean condition, and positive (hunters retrieved good individuals compared to cohort mean) in the cohort of poor mean condition. Despite significant variation in cohort condition, the duckling condition of individuals retrieved during their first season from the cohorts of high and poor mean condition was comparable. The condition of first‐year retrieved birds was not significantly different from the condition of birds retrieved during their second and third year, when all years were pooled. As there is a significant positive relationship within cohorts between duckling condition and recruitment of (female) eiders, the present results suggest, 1) that hunting vulnerability in the eider is related to a specific (poor) level of body condition attained prior to fledging, and 2) that hunting tends to remove the poorest individuals present at the time when the hunting season opens. Article in Journal/Newspaper Common Eider Somateria mollissima Wiley Online Library Wildlife Biology 7 2 97 104 |
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Open Polar |
collection |
Wiley Online Library |
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crwiley |
language |
English |
description |
Condition related pre‐breeding hunting vulnerability in the common eider Somateria mollissima, i.e. the relationship between body condition attained as a duckling and the probability of being shot, was analysed from recoveries of hunter‐retrieved birds ringed in the Stavns Fjord colony in Denmark during 1991–1995. Mean duckling cohort condition showed significant variation between years, but the proportions of birds retrieved during the first three seasons were similar (4.9% ± 1.4 SD). The proportion of birds retrieved by hunters declined from 3.9% in the first year to 0.64% and 0.38% in the second and third year, respectively. A condition bias was found in first‐year retrieved birds in the cohorts with the highest and poorest mean condition, but not in the cohorts of intermediate condition. In accordance with a priori predictions regarding condition related non‐hunting mortality during the period between marking and the opening of the hunting season, the direction of the bias was negative (hunters retrieved poor individuals compared to cohort mean) in the cohort of high mean condition, and positive (hunters retrieved good individuals compared to cohort mean) in the cohort of poor mean condition. Despite significant variation in cohort condition, the duckling condition of individuals retrieved during their first season from the cohorts of high and poor mean condition was comparable. The condition of first‐year retrieved birds was not significantly different from the condition of birds retrieved during their second and third year, when all years were pooled. As there is a significant positive relationship within cohorts between duckling condition and recruitment of (female) eiders, the present results suggest, 1) that hunting vulnerability in the eider is related to a specific (poor) level of body condition attained prior to fledging, and 2) that hunting tends to remove the poorest individuals present at the time when the hunting season opens. |
format |
Article in Journal/Newspaper |
author |
Christensen, Thomas Kjær |
spellingShingle |
Christensen, Thomas Kjær Effects of duckling body condition on hunting vulnerability in juvenile and immature common eiders Somateria mollissima |
author_facet |
Christensen, Thomas Kjær |
author_sort |
Christensen, Thomas Kjær |
title |
Effects of duckling body condition on hunting vulnerability in juvenile and immature common eiders Somateria mollissima |
title_short |
Effects of duckling body condition on hunting vulnerability in juvenile and immature common eiders Somateria mollissima |
title_full |
Effects of duckling body condition on hunting vulnerability in juvenile and immature common eiders Somateria mollissima |
title_fullStr |
Effects of duckling body condition on hunting vulnerability in juvenile and immature common eiders Somateria mollissima |
title_full_unstemmed |
Effects of duckling body condition on hunting vulnerability in juvenile and immature common eiders Somateria mollissima |
title_sort |
effects of duckling body condition on hunting vulnerability in juvenile and immature common eiders somateria mollissima |
publisher |
Wiley |
publishDate |
2001 |
url |
http://dx.doi.org/10.2981/wlb.2001.013 https://onlinelibrary.wiley.com/doi/full-xml/10.2981/wlb.2001.013 https://onlinelibrary.wiley.com/doi/pdf/10.2981/wlb.2001.013 |
genre |
Common Eider Somateria mollissima |
genre_facet |
Common Eider Somateria mollissima |
op_source |
Wildlife Biology volume 7, issue 2, page 97-104 ISSN 1903-220X 1903-220X |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.2981/wlb.2001.013 |
container_title |
Wildlife Biology |
container_volume |
7 |
container_issue |
2 |
container_start_page |
97 |
op_container_end_page |
104 |
_version_ |
1809906001503059968 |