Trade-offs between sight lines and escape habitat determine spatial strategies of risk management by a keystone herbivore
Prey individuals possess four basic strategies to manage predation risk while foraging: time allocation, space use, apprehension, and foraging tenacity. But there are no direct tests of theory detailing how spatial strategies change and covary from fine to coarse scales of environmental variability....
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
| Published: |
Canadian Science Publishing
2018-03-01
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| Series: | FACETS |
| Subjects: | |
| Online Access: | http://www.facetsjournal.com/doi/10.1139/facets-2016-0062 |
| _version_ | 1818016547032006656 |
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| author | Douglas W. Morris Sundararaj Vijayan |
| author_facet | Douglas W. Morris Sundararaj Vijayan |
| author_sort | Douglas W. Morris |
| collection | DOAJ |
| description | Prey individuals possess four basic strategies to manage predation risk while foraging: time allocation, space use, apprehension, and foraging tenacity. But there are no direct tests of theory detailing how spatial strategies change and covary from fine to coarse scales of environmental variability. We address this shortcoming with experiments that estimated space use and vigilance of snowshoe hares while we measured foraging tenacity in artificial resource patches placed in risky open versus safe alder habitat. Hares employed only two of eight a priori options to manage risk. Hares increased vigilance and reduced foraging in open areas as the distance from cover increased. Hares did not differentiate between open and alder habitats, increase vigilance at the coarse-grained scale, or reduce vigilance and foraging tenacity under supplemental cover. Hares were more vigilant in the putatively safe alder than in the purportedly risky open habitat. These apparently paradoxical results appear to reflect a trade-off between the benefit of alder as escape habitat and the cost of obscured sight lines that reduce predator detection. The trade-off also appears to equalize safety between habitats at small scales and suggests that common-sense predictions detailing how prey reduce risk may make no sense at all. |
| first_indexed | 2024-04-14T07:13:52Z |
| format | Article |
| id | doaj.art-ab804f11f2f944fa96e227b427ed6a2f |
| institution | Directory Open Access Journal |
| issn | 2371-1671 2371-1671 |
| language | English |
| last_indexed | 2024-04-14T07:13:52Z |
| publishDate | 2018-03-01 |
| publisher | Canadian Science Publishing |
| record_format | Article |
| series | FACETS |
| spelling | doaj.art-ab804f11f2f944fa96e227b427ed6a2f2022-12-22T02:06:21ZengCanadian Science PublishingFACETS2371-16712371-16712018-03-01333835710.1139/facets-2016-0062Trade-offs between sight lines and escape habitat determine spatial strategies of risk management by a keystone herbivoreDouglas W. Morris0Sundararaj Vijayan1Department of Biology, Lakehead University, Thunder Bay, ON P7B 5E1, Canada.Department of Biology, Lakehead University, Thunder Bay, ON P7B 5E1, Canada.Prey individuals possess four basic strategies to manage predation risk while foraging: time allocation, space use, apprehension, and foraging tenacity. But there are no direct tests of theory detailing how spatial strategies change and covary from fine to coarse scales of environmental variability. We address this shortcoming with experiments that estimated space use and vigilance of snowshoe hares while we measured foraging tenacity in artificial resource patches placed in risky open versus safe alder habitat. Hares employed only two of eight a priori options to manage risk. Hares increased vigilance and reduced foraging in open areas as the distance from cover increased. Hares did not differentiate between open and alder habitats, increase vigilance at the coarse-grained scale, or reduce vigilance and foraging tenacity under supplemental cover. Hares were more vigilant in the putatively safe alder than in the purportedly risky open habitat. These apparently paradoxical results appear to reflect a trade-off between the benefit of alder as escape habitat and the cost of obscured sight lines that reduce predator detection. The trade-off also appears to equalize safety between habitats at small scales and suggests that common-sense predictions detailing how prey reduce risk may make no sense at all.http://www.facetsjournal.com/doi/10.1139/facets-2016-0062foraginggiving-up densityhabitatkeystone herbivorepredation riskrisk managementspatial scalesnowshoe hare |
| spellingShingle | Douglas W. Morris Sundararaj Vijayan Trade-offs between sight lines and escape habitat determine spatial strategies of risk management by a keystone herbivore FACETS foraging giving-up density habitat keystone herbivore predation risk risk management spatial scale snowshoe hare |
| title | Trade-offs between sight lines and escape habitat determine spatial strategies of risk management by a keystone herbivore |
| title_full | Trade-offs between sight lines and escape habitat determine spatial strategies of risk management by a keystone herbivore |
| title_fullStr | Trade-offs between sight lines and escape habitat determine spatial strategies of risk management by a keystone herbivore |
| title_full_unstemmed | Trade-offs between sight lines and escape habitat determine spatial strategies of risk management by a keystone herbivore |
| title_short | Trade-offs between sight lines and escape habitat determine spatial strategies of risk management by a keystone herbivore |
| title_sort | trade offs between sight lines and escape habitat determine spatial strategies of risk management by a keystone herbivore |
| topic | foraging giving-up density habitat keystone herbivore predation risk risk management spatial scale snowshoe hare |
| url | http://www.facetsjournal.com/doi/10.1139/facets-2016-0062 |
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