The Influence of Food Density, Flock Size, and Disturbance on the Functional Response of Bewick’s Swans ( Cygnus columbianus bewickii ) in Wintering Habitats
Perceiving how animals adjust their feeding rate under a variety of environmental conditions and understanding the tradeoffs in their foraging strategies are necessary for conservation. The Holling functional response, which describes the relationship of feeding rate and food density to searching ra...
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ftdoajarticles:oai:doaj.org/article:73a05cd44b864d629e179dc91b6d875d 2023-05-15T15:59:44+02:00 The Influence of Food Density, Flock Size, and Disturbance on the Functional Response of Bewick’s Swans ( Cygnus columbianus bewickii ) in Wintering Habitats Chao Yu Lizhi Zhou Nazia Mahtab Shaojun Fan Yunwei Song 2019-11-01T00:00:00Z https://doi.org/10.3390/ani9110946 https://doaj.org/article/73a05cd44b864d629e179dc91b6d875d EN eng MDPI AG https://www.mdpi.com/2076-2615/9/11/946 https://doaj.org/toc/2076-2615 2076-2615 doi:10.3390/ani9110946 https://doaj.org/article/73a05cd44b864d629e179dc91b6d875d Animals, Vol 9, Iss 11, p 946 (2019) functional response feeding rate handling time searching rate vigilance food item density flock size bewick’s swans Veterinary medicine SF600-1100 Zoology QL1-991 article 2019 ftdoajarticles https://doi.org/10.3390/ani9110946 2022-12-31T07:21:22Z Perceiving how animals adjust their feeding rate under a variety of environmental conditions and understanding the tradeoffs in their foraging strategies are necessary for conservation. The Holling functional response, which describes the relationship of feeding rate and food density to searching rate and handling time, has been applied to a range of waterbirds, especially with regard to Type II functional responses that describe an increasing feeding rate with food density but at a decelerating rate as the curve approaches the asymptote. However, feeding behavior components (feeding rate, searching rate, and handling time) are influenced by factors besides prey density, such as vigilance and flock size. In this study, we aim to elucidate how Bewick’s swans ( Cygnus columbianus bewickii ) adopt flexible foraging strategies and vary their feeding behavior components in response to disturbance, flock size, and food density. We collected focal sampling data on the foraging behavior of swans that foraged rice grains, foxnut seeds, and tubers in paddy field, foxnut pond, and lake habitats, respectively, in Shengjin and Huangpi lakes during winter from 2016 to 2018. The observed feeding rate was not correlated with food density and displayed a positive relationship with searching rate but negative relationships with handling time, flock size, overall vigilance time, and disturbance time. Handling time was negatively correlated with food density and flock size, yet it increased with disturbance, overall vigilance time, and normal vigilance time. Searching rate was negatively correlated with food density, flock size, and disturbance time. Feeding rate was affected by the combined effects of handling time and searching rate, as well as food density and searching rate. The shape of the observed functional response could not be fitted to Holling’s disc equation. However, the disc equation of the predicted feeding rate of wintering swans was found to be driven by food density. This provides insight into how wintering ... Article in Journal/Newspaper Cygnus columbianus Directory of Open Access Journals: DOAJ Articles Animals 9 11 946 |
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topic |
functional response feeding rate handling time searching rate vigilance food item density flock size bewick’s swans Veterinary medicine SF600-1100 Zoology QL1-991 |
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functional response feeding rate handling time searching rate vigilance food item density flock size bewick’s swans Veterinary medicine SF600-1100 Zoology QL1-991 Chao Yu Lizhi Zhou Nazia Mahtab Shaojun Fan Yunwei Song The Influence of Food Density, Flock Size, and Disturbance on the Functional Response of Bewick’s Swans ( Cygnus columbianus bewickii ) in Wintering Habitats |
topic_facet |
functional response feeding rate handling time searching rate vigilance food item density flock size bewick’s swans Veterinary medicine SF600-1100 Zoology QL1-991 |
description |
Perceiving how animals adjust their feeding rate under a variety of environmental conditions and understanding the tradeoffs in their foraging strategies are necessary for conservation. The Holling functional response, which describes the relationship of feeding rate and food density to searching rate and handling time, has been applied to a range of waterbirds, especially with regard to Type II functional responses that describe an increasing feeding rate with food density but at a decelerating rate as the curve approaches the asymptote. However, feeding behavior components (feeding rate, searching rate, and handling time) are influenced by factors besides prey density, such as vigilance and flock size. In this study, we aim to elucidate how Bewick’s swans ( Cygnus columbianus bewickii ) adopt flexible foraging strategies and vary their feeding behavior components in response to disturbance, flock size, and food density. We collected focal sampling data on the foraging behavior of swans that foraged rice grains, foxnut seeds, and tubers in paddy field, foxnut pond, and lake habitats, respectively, in Shengjin and Huangpi lakes during winter from 2016 to 2018. The observed feeding rate was not correlated with food density and displayed a positive relationship with searching rate but negative relationships with handling time, flock size, overall vigilance time, and disturbance time. Handling time was negatively correlated with food density and flock size, yet it increased with disturbance, overall vigilance time, and normal vigilance time. Searching rate was negatively correlated with food density, flock size, and disturbance time. Feeding rate was affected by the combined effects of handling time and searching rate, as well as food density and searching rate. The shape of the observed functional response could not be fitted to Holling’s disc equation. However, the disc equation of the predicted feeding rate of wintering swans was found to be driven by food density. This provides insight into how wintering ... |
format |
Article in Journal/Newspaper |
author |
Chao Yu Lizhi Zhou Nazia Mahtab Shaojun Fan Yunwei Song |
author_facet |
Chao Yu Lizhi Zhou Nazia Mahtab Shaojun Fan Yunwei Song |
author_sort |
Chao Yu |
title |
The Influence of Food Density, Flock Size, and Disturbance on the Functional Response of Bewick’s Swans ( Cygnus columbianus bewickii ) in Wintering Habitats |
title_short |
The Influence of Food Density, Flock Size, and Disturbance on the Functional Response of Bewick’s Swans ( Cygnus columbianus bewickii ) in Wintering Habitats |
title_full |
The Influence of Food Density, Flock Size, and Disturbance on the Functional Response of Bewick’s Swans ( Cygnus columbianus bewickii ) in Wintering Habitats |
title_fullStr |
The Influence of Food Density, Flock Size, and Disturbance on the Functional Response of Bewick’s Swans ( Cygnus columbianus bewickii ) in Wintering Habitats |
title_full_unstemmed |
The Influence of Food Density, Flock Size, and Disturbance on the Functional Response of Bewick’s Swans ( Cygnus columbianus bewickii ) in Wintering Habitats |
title_sort |
influence of food density, flock size, and disturbance on the functional response of bewick’s swans ( cygnus columbianus bewickii ) in wintering habitats |
publisher |
MDPI AG |
publishDate |
2019 |
url |
https://doi.org/10.3390/ani9110946 https://doaj.org/article/73a05cd44b864d629e179dc91b6d875d |
genre |
Cygnus columbianus |
genre_facet |
Cygnus columbianus |
op_source |
Animals, Vol 9, Iss 11, p 946 (2019) |
op_relation |
https://www.mdpi.com/2076-2615/9/11/946 https://doaj.org/toc/2076-2615 2076-2615 doi:10.3390/ani9110946 https://doaj.org/article/73a05cd44b864d629e179dc91b6d875d |
op_doi |
https://doi.org/10.3390/ani9110946 |
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Animals |
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9 |
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11 |
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946 |
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1766395650762604544 |