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Rapidly changing climate at high latitudes has triggered a search for bellwethers of ecological change there. If the initial signs of change can be identified, perhaps we can predict where these changes will lead. Large-bodied, terrestrial herbivores are potential candidates for bellwether taxa because of the key roles they play in some ecological communities. Here, we assembled historical, archaeological, and paleontological records of moose ( Alces alces (Linnaeus, 1758)) from the western Arctic and subarctic. The results showed that rather than having recently invaded tundra regions in response to post Little Ice Age warming, moose have inhabited river corridors several hundred kilometres north of the closed, boreal forest since they first colonized North America across the Bering Land Bridge ca. 14 000 years ago. The combination of high mobility, fluctuation-prone metapopulations, and reliance on early successional vegetation makes changes in the northern range limits of moose undependable bellwethers for other biotic responses to changing climate. The history of moose at high latitudes illustrates how understanding what happened in prehistory is useful for correctly assigning significance and cause to present-day ecological changes.
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Enhanced shrub growth in the Arctic increases habitat connectivity for browsing herbivores
Abstract Habitat connectivity is a key factor influencing species range dynamics. Rapid warming in the Arctic is leading to widespread heterogeneous shrub expansion, but impacts of these habitat changes on range dynamics for large herbivores are not well understood. We use the climate–shrub–moose system of northern Alaska as a case study to examine how shrub habitat will respond to predicted future warming, and how these changes may impact habitat connectivity and the distribution of moose (Alces alces). We used a 19 year moose location dataset, a 568 km transect of field shrub sampling, and forecasted warming scenarios with regional downscaling to map current and projected shrub habitat for moose on the North Slope of Alaska. The tall‐shrub habitat for moose exhibited a dendritic spatial configuration correlated with river corridor networks and mean July temperature. Warming scenarios predict that moose habitat will more than double by 2099. Forecasted warming is predicted to increase the spatial cohesion of the habitat network that diminishes effects of fragmentation, which improves overall habitat quality and likely expands the range of moose. These findings demonstrate how climate change may increase habitat connectivity and alter the distributions of shrub herbivores in the Arctic, including creation of novel communities and ecosystems.
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- PAR ID:
- 10452121
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Global Change Biology
- Volume:
- 26
- Issue:
- 7
- ISSN:
- 1354-1013
- Format(s):
- Medium: X Size: p. 3809-3820
- Size(s):
- p. 3809-3820
- Sponsoring Org:
- National Science Foundation
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