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Abstract Beavers were not previously recognized as an Arctic species, and their engineering in the tundra is considered negligible. Recent findings suggest that beavers have moved into Arctic tundra regions and are controlling surface water dynamics, which strongly influence permafrost and landscape stability. Here we use 70 years of satellite images and aerial photography to show the scale and magnitude of northwestward beaver expansion in Alaska, indicated by the construction of over 10,000 beaver ponds in the Arctic tundra. The number of beaver ponds doubled in most areas between ~ 2003 and ~ 2017. Earlier stages of beaver engineering are evident in ~ 1980 imagery, and there is no evidence of beaver engineering in ~ 1952 imagery, consistent with observations from Indigenous communities describing the influx of beavers over the period. Rapidly expanding beaver engineering has created a tundra disturbance regime that appears to be thawing permafrost and exacerbating the effects of climate change.
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Beaver Pond Locations in Arctic Alaska, 1949 to 2020.
Beavers were not previously recognized as an Arctic species, and their engineering in the tundra is considered negligible. Recent findings suggest that beavers have moved into arctic tundra regions and are controlling surface water dynamics, which strongly influence permafrost and landscape stability. These data show beaver pond locations in the Alaska Arctic identified in aerial photography and satellite imagery. Black and white aerial photography is from 1949-55, color infrared aerial photography (AHAP) is from 1976-84, and high-resolution satellite imagery is from 2000-2020. The number of beaver ponds doubled in most areas of ~2003 and ~2017 images. Earlier stages of beaver engineering are evident in ~1980 imagery, and there is no evidence of beaver engineering in ~1952 imagery, consistent with observations from Indigenous communities describing the influx of beavers over the period.
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- Award ID(s):
- 1850578
- PAR ID:
- 10473924
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- beaver pond arctic tundra ecosystem engineer
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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