Critical summer foraging tradeoffs in a subarctic ungulate
Abstract Summer diets are crucial for large herbivores in the subarctic and are affected by weather, harassment from insects and a variety of environmental changes linked to climate. Yet, understanding foraging behavior and diet of large herbivores is challenging in the subarctic because of their re...
Published in: | Ecology and Evolution |
---|---|
Main Authors: | , , , , , , |
Other Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Wiley
2021
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1002/ece3.8349 https://onlinelibrary.wiley.com/doi/pdf/10.1002/ece3.8349 https://onlinelibrary.wiley.com/doi/full-xml/10.1002/ece3.8349 |
id |
crwiley:10.1002/ece3.8349 |
---|---|
record_format |
openpolar |
spelling |
crwiley:10.1002/ece3.8349 2024-10-13T14:10:25+00:00 Critical summer foraging tradeoffs in a subarctic ungulate Ehlers, Libby Coulombe, Gabrielle Herriges, Jim Bentzen, Torsten Suitor, Michael Joly, Kyle Hebblewhite, Mark National Park Service University of Montana Alaska Department of Fish and Game U.S. Bureau of Land Management 2021 http://dx.doi.org/10.1002/ece3.8349 https://onlinelibrary.wiley.com/doi/pdf/10.1002/ece3.8349 https://onlinelibrary.wiley.com/doi/full-xml/10.1002/ece3.8349 en eng Wiley http://creativecommons.org/licenses/by/4.0/ Ecology and Evolution volume 11, issue 24, page 17835-17872 ISSN 2045-7758 2045-7758 journal-article 2021 crwiley https://doi.org/10.1002/ece3.8349 2024-09-17T04:45:40Z Abstract Summer diets are crucial for large herbivores in the subarctic and are affected by weather, harassment from insects and a variety of environmental changes linked to climate. Yet, understanding foraging behavior and diet of large herbivores is challenging in the subarctic because of their remote ranges. We used GPS video‐camera collars to observe behaviors and summer diets of the migratory Fortymile Caribou Herd ( Rangifer tarandus granti ) across Alaska, USA and the Yukon, Canada. First, we characterized caribou behavior. Second, we tested if videos could be used to quantify changes in the probability of eating events. Third, we estimated summer diets at the finest taxonomic resolution possible through videos. Finally, we compared summer diet estimates from video collars to microhistological analysis of fecal pellets. We classified 18,134 videos from 30 female caribou over two summers (2018 and 2019). Caribou behaviors included eating (mean = 43.5%), ruminating (25.6%), travelling (14.0%), stationary awake (11.3%) and napping (5.1%). Eating was restricted by insect harassment. We classified forage(s) consumed in 5,549 videos where diet composition (monthly) highlighted a strong tradeoff between lichens and shrubs; shrubs dominated diets in June and July when lichen use declined. We identified 63 species, 70 genus and 33 family groups of summer forages from videos. After adjusting for digestibility, monthly estimates of diet composition were strongly correlated at the scale of the forage functional type (i.e., forage groups composed of forbs, graminoids, mosses, shrubs and lichens; r = 0.79, p < .01). Using video collars, we identified (1) a pronounced tradeoff in summer foraging between lichens and shrubs and (2) the costs of insect harassment on eating. Understanding caribou foraging ecology is needed to plan for their long‐term conservation across the circumpolar north, and video collars can provide a powerful approach across remote regions. Article in Journal/Newspaper Rangifer tarandus Subarctic Alaska Yukon Wiley Online Library Yukon Canada Ecology and Evolution 11 24 17835 17872 |
institution |
Open Polar |
collection |
Wiley Online Library |
op_collection_id |
crwiley |
language |
English |
description |
Abstract Summer diets are crucial for large herbivores in the subarctic and are affected by weather, harassment from insects and a variety of environmental changes linked to climate. Yet, understanding foraging behavior and diet of large herbivores is challenging in the subarctic because of their remote ranges. We used GPS video‐camera collars to observe behaviors and summer diets of the migratory Fortymile Caribou Herd ( Rangifer tarandus granti ) across Alaska, USA and the Yukon, Canada. First, we characterized caribou behavior. Second, we tested if videos could be used to quantify changes in the probability of eating events. Third, we estimated summer diets at the finest taxonomic resolution possible through videos. Finally, we compared summer diet estimates from video collars to microhistological analysis of fecal pellets. We classified 18,134 videos from 30 female caribou over two summers (2018 and 2019). Caribou behaviors included eating (mean = 43.5%), ruminating (25.6%), travelling (14.0%), stationary awake (11.3%) and napping (5.1%). Eating was restricted by insect harassment. We classified forage(s) consumed in 5,549 videos where diet composition (monthly) highlighted a strong tradeoff between lichens and shrubs; shrubs dominated diets in June and July when lichen use declined. We identified 63 species, 70 genus and 33 family groups of summer forages from videos. After adjusting for digestibility, monthly estimates of diet composition were strongly correlated at the scale of the forage functional type (i.e., forage groups composed of forbs, graminoids, mosses, shrubs and lichens; r = 0.79, p < .01). Using video collars, we identified (1) a pronounced tradeoff in summer foraging between lichens and shrubs and (2) the costs of insect harassment on eating. Understanding caribou foraging ecology is needed to plan for their long‐term conservation across the circumpolar north, and video collars can provide a powerful approach across remote regions. |
author2 |
National Park Service University of Montana Alaska Department of Fish and Game U.S. Bureau of Land Management |
format |
Article in Journal/Newspaper |
author |
Ehlers, Libby Coulombe, Gabrielle Herriges, Jim Bentzen, Torsten Suitor, Michael Joly, Kyle Hebblewhite, Mark |
spellingShingle |
Ehlers, Libby Coulombe, Gabrielle Herriges, Jim Bentzen, Torsten Suitor, Michael Joly, Kyle Hebblewhite, Mark Critical summer foraging tradeoffs in a subarctic ungulate |
author_facet |
Ehlers, Libby Coulombe, Gabrielle Herriges, Jim Bentzen, Torsten Suitor, Michael Joly, Kyle Hebblewhite, Mark |
author_sort |
Ehlers, Libby |
title |
Critical summer foraging tradeoffs in a subarctic ungulate |
title_short |
Critical summer foraging tradeoffs in a subarctic ungulate |
title_full |
Critical summer foraging tradeoffs in a subarctic ungulate |
title_fullStr |
Critical summer foraging tradeoffs in a subarctic ungulate |
title_full_unstemmed |
Critical summer foraging tradeoffs in a subarctic ungulate |
title_sort |
critical summer foraging tradeoffs in a subarctic ungulate |
publisher |
Wiley |
publishDate |
2021 |
url |
http://dx.doi.org/10.1002/ece3.8349 https://onlinelibrary.wiley.com/doi/pdf/10.1002/ece3.8349 https://onlinelibrary.wiley.com/doi/full-xml/10.1002/ece3.8349 |
geographic |
Yukon Canada |
geographic_facet |
Yukon Canada |
genre |
Rangifer tarandus Subarctic Alaska Yukon |
genre_facet |
Rangifer tarandus Subarctic Alaska Yukon |
op_source |
Ecology and Evolution volume 11, issue 24, page 17835-17872 ISSN 2045-7758 2045-7758 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1002/ece3.8349 |
container_title |
Ecology and Evolution |
container_volume |
11 |
container_issue |
24 |
container_start_page |
17835 |
op_container_end_page |
17872 |
_version_ |
1812817684592590848 |