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Qualitative studies have suggested that forest changes following a wildfire can challenge a hunter's ability to harvest big game, such as moose (Alces alces). Quantitative effects have not been estimated. Given the increasing prevalence of wildfires, the strong linkages between wildfire and moose habitat, and the importance of moose to the people of the boreal region of North America, our goal was to assess if and how moose harvest patterns changed immediately following a wildfire. To address that goal, we used 36 years (1984-2019) of spatially-explicit wildfire and moose harvest data in Alaska to compare moose harvest variables the year before and year after a wildfire occurred. With a few exceptions, the number of hunters, kills, and success rates were similar (p > 0.05, Effect size < 0.3) between pre- and post-wildfire years. We estimated a weak to moderate effect on change in moose hunter numbers, kills, and success rate in only a small percentage (1.5%) of wildfires that burned a very large proportion (>38%) of a moose harvest reporting unit. Our findings suggest that wildfire has not caused a clear and functional quantitative effect on hunters’ ability to harvest moose in Alaska.
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AVAILABILITY AND USE OF MOOSE BROWSE IN RESPONSE TO POST-FIRE SUCCESSION ON KANUTI NATIONAL WILDLIFE REFUGE, ALASKA
Wildfire is a prominent landscape-level disturbance in interior Alaska and associated vegetation changes affect quantity and quality of moose (Alces alces) habitat. These changes are important to land and wildlife managers responsible for managing habitat and ensuring sustained yield of game species such as moose. Considering the changing fire regime related to climate change, we explored post-fire dynamics of moose habitat to broaden understanding of local habitat characteristics associated with wildfire on the Kanuti National Wildlife Refuge in interior Alaska. We studied 34 sites in different aged stands (2005 burn, 1990 burn, 1972 burn, and unburned in the last 80 years) in August 2012 and 2013 to estimate summer browse density, biomass production, and browse use, and revisited each site the following March to estimate winter browse availability and offtake. We also used location data from 51 radio-collared moose to quantify use of burns on the Kanuti National Wildlife Refuge. We found that summer density and biomass of preferred browse was highest at sites in the 1990 burn, although use of burns varied seasonally. Despite high biomass in the most recent 2005 burn, radio-collared moose avoided burns <11 years old in summer and had preference for older stands (>30 years old). Winter browse offtake was highest in the 1990 and 1972 burns despite relatively high biomass available in the 2005 burn. The disparate use of burns, particularly low use of the 2005 burn, likely reflected a combination of influences including species composition and preference, predator avoidance strategies, a low density moose population, and historic moose distribution patterns.
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- Award ID(s):
- 1636476
- PAR ID:
- 10212891
- Date Published:
- Journal Name:
- Alces
- Volume:
- 55
- ISSN:
- 2293-6629
- Page Range / eLocation ID:
- 67-89
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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