Document Type
Article
Journal/Book Title/Conference
Scientific Reports
Author ORCID Identifier
Christian John https://orcid.org/0000-0002-6249-040X
Tal Avgar https://orcid.org/0000-0002-8764-6976
Karl Rittger https://orcid.org/0000-0002-8733-434X
Justine A. Smith https://orcid.org/0000-0001-8753-4061
Thomas Stephenson https://orcid.org/0000-0002-9412-8309
Eric Post https://orcid.org/0000-0002-9471-5351
Volume
14
Publisher
Nature Publishing Group
Publication Date
7-2-2024
Journal Article Version
Version of Record
First Page
1
Last Page
11
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Abstract
Climate change reduces snowpack, advances snowmelt phenology, drives summer warming, alters growing season precipitation regimes, and consequently modifies vegetation phenology in mountain systems. Elevational migrants track spatial variation in seasonal plant growth by moving between ranges at different elevations during spring, so climate-driven vegetation change may disrupt historic benefits of migration. Elevational migrants can furthermore cope with short-term environmental variability by undertaking brief vertical movements to refugia when sudden adverse conditions arise. We uncover drivers of fine-scale vertical movement variation during upland migration in an endangered alpine specialist, Sierra Nevada bighorn sheep (Ovis canadensis sierrae) using a 20-year study of GPS collar data collected from 311 unique individuals. We used integrated step-selection analysis to determine factors that promote vertical movements and drive selection of destinations following vertical movements. Our results reveal that relatively high temperatures consistently drive uphill movements, while precipitation likely drives downhill movements. Furthermore, bighorn select destinations a their peak annual biomass and maximal time since snowmelt. These results indicate that although Sierra Nevada bighorn sheep seek out foraging opportunities related to landscape phenology, they compensate for short-term environmental stressors by undertaking brief up- and downslope vertical movements. Migrants may therefore be impacted by future warming and increased storm frequency or intensity, with shifts in annual migration timing and fine-scale vertical movement
Recommended Citation
John, C., Avgar, T., Rittger, K. et al. Pursuit and escape drive fine-scale movement variation during migration in a temperate alpine ungulate. Sci Rep 14, 15068 (2024). https://doi.org/10.1038/s41598-024-65948-8
