Seeing sunlit owls in a new light: orienting Snowy Owls may not be displaying
Snowy Owls Bubo scandiacus often face the sun when sitting on the ground or when perched. Such sun‐orienting has been suggested to represent a visual display to conspecifics but other explanations have not been thoroughly examined. We observed the orientation of wintering Snowy Owls to both the sun...
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Online Access: | http://dx.doi.org/10.1111/ibi.12533 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fibi.12533 https://onlinelibrary.wiley.com/doi/pdf/10.1111/ibi.12533 |
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crwiley:10.1111/ibi.12533 2024-06-02T08:04:38+00:00 Seeing sunlit owls in a new light: orienting Snowy Owls may not be displaying Wiebe, Karen L. Chang, Alexander M. Kenneth M. Molson Foundation 2017 http://dx.doi.org/10.1111/ibi.12533 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fibi.12533 https://onlinelibrary.wiley.com/doi/pdf/10.1111/ibi.12533 en eng Wiley http://onlinelibrary.wiley.com/termsAndConditions#vor Ibis volume 160, issue 1, page 62-70 ISSN 0019-1019 1474-919X journal-article 2017 crwiley https://doi.org/10.1111/ibi.12533 2024-05-03T10:43:04Z Snowy Owls Bubo scandiacus often face the sun when sitting on the ground or when perched. Such sun‐orienting has been suggested to represent a visual display to conspecifics but other explanations have not been thoroughly examined. We observed the orientation of wintering Snowy Owls to both the sun and the wind, and their perching behaviour during two winters in central Saskatchewan, Canada. We proposed three new explanations for sun orientation in addition to the display hypothesis: thermoregulation, hunting and defence against predators. On sunny days, 44% of 710 Owls faced the sun; this was non‐random because few did so on overcast days. Sun‐ as opposed to wind‐orienting was strongly associated with weather conditions. Logistic regressions indicated that at temperatures below –13 °C and at wind speeds greater than about 18 km/h, Owls tended to orient to the wind rather than to the sun. The likelihood of wind‐orienting increased if the Owl perched above the ground, whereas the likelihood of sun‐orientating increased slightly when the Owl was sitting on the ground. There was no difference between the sexes in orienting behaviour. Snowy Owls seemed to prioritize wind‐orienting for thermoregulation but the results are also consistent with the idea that sun‐orientation can reduce heat loss. Facing into the sun did not support the hunting explanation because the birds would have been blinded and not able to see prey, but was consistent with the protection explanation if it helps to increase vigilance against enemies. Although we cannot completely rule out the display explanation, the spatial context of sunning Owls and a lack of a sex effect makes it unlikely that this is the main function. Instead, Owls seem to trade‐off wind‐ vs. sun‐orienting according to the prevailing weather conditions and do so mainly to thermoregulate and perhaps to maintain vigilance. Article in Journal/Newspaper Bubo scandiacus Wiley Online Library Canada Ibis 160 1 62 70 |
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Open Polar |
collection |
Wiley Online Library |
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crwiley |
language |
English |
description |
Snowy Owls Bubo scandiacus often face the sun when sitting on the ground or when perched. Such sun‐orienting has been suggested to represent a visual display to conspecifics but other explanations have not been thoroughly examined. We observed the orientation of wintering Snowy Owls to both the sun and the wind, and their perching behaviour during two winters in central Saskatchewan, Canada. We proposed three new explanations for sun orientation in addition to the display hypothesis: thermoregulation, hunting and defence against predators. On sunny days, 44% of 710 Owls faced the sun; this was non‐random because few did so on overcast days. Sun‐ as opposed to wind‐orienting was strongly associated with weather conditions. Logistic regressions indicated that at temperatures below –13 °C and at wind speeds greater than about 18 km/h, Owls tended to orient to the wind rather than to the sun. The likelihood of wind‐orienting increased if the Owl perched above the ground, whereas the likelihood of sun‐orientating increased slightly when the Owl was sitting on the ground. There was no difference between the sexes in orienting behaviour. Snowy Owls seemed to prioritize wind‐orienting for thermoregulation but the results are also consistent with the idea that sun‐orientation can reduce heat loss. Facing into the sun did not support the hunting explanation because the birds would have been blinded and not able to see prey, but was consistent with the protection explanation if it helps to increase vigilance against enemies. Although we cannot completely rule out the display explanation, the spatial context of sunning Owls and a lack of a sex effect makes it unlikely that this is the main function. Instead, Owls seem to trade‐off wind‐ vs. sun‐orienting according to the prevailing weather conditions and do so mainly to thermoregulate and perhaps to maintain vigilance. |
author2 |
Kenneth M. Molson Foundation |
format |
Article in Journal/Newspaper |
author |
Wiebe, Karen L. Chang, Alexander M. |
spellingShingle |
Wiebe, Karen L. Chang, Alexander M. Seeing sunlit owls in a new light: orienting Snowy Owls may not be displaying |
author_facet |
Wiebe, Karen L. Chang, Alexander M. |
author_sort |
Wiebe, Karen L. |
title |
Seeing sunlit owls in a new light: orienting Snowy Owls may not be displaying |
title_short |
Seeing sunlit owls in a new light: orienting Snowy Owls may not be displaying |
title_full |
Seeing sunlit owls in a new light: orienting Snowy Owls may not be displaying |
title_fullStr |
Seeing sunlit owls in a new light: orienting Snowy Owls may not be displaying |
title_full_unstemmed |
Seeing sunlit owls in a new light: orienting Snowy Owls may not be displaying |
title_sort |
seeing sunlit owls in a new light: orienting snowy owls may not be displaying |
publisher |
Wiley |
publishDate |
2017 |
url |
http://dx.doi.org/10.1111/ibi.12533 https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fibi.12533 https://onlinelibrary.wiley.com/doi/pdf/10.1111/ibi.12533 |
geographic |
Canada |
geographic_facet |
Canada |
genre |
Bubo scandiacus |
genre_facet |
Bubo scandiacus |
op_source |
Ibis volume 160, issue 1, page 62-70 ISSN 0019-1019 1474-919X |
op_rights |
http://onlinelibrary.wiley.com/termsAndConditions#vor |
op_doi |
https://doi.org/10.1111/ibi.12533 |
container_title |
Ibis |
container_volume |
160 |
container_issue |
1 |
container_start_page |
62 |
op_container_end_page |
70 |
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1800749280430915584 |