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Fire effects on the Point Reyes Mountain Beaver ( Aplodontia rufa phaea ) at Point Reyes National Seashore, 10 years after the Vision Fire

Gary M. Fellers·Michael Osbourn
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Abstract

The 1995 Vision Fire burned 5000 ha and destroyed 40% of the habitat of the Point Reyes Mountain Beaver ( Aplodontia rufa phaea ). Surveys immediately post-fire and in 2000 showed that only 0.4 to 1.7% of Mountain Beavers within the burn area survived. In 2000, dense, ground-hugging Blue-blossom Ceanothus ( Ceanothus thrysiflorus ) appeared to make coastal scrub thickets much less suitable for Mountain Beavers even though the number of burrows at our 11 study sites had returned to 88% of pre-fire numbers. In 2005 (10 y post-fire), the habitat appeared to be better for Mountain Beavers; Blue-blossom Ceanothus had diminished and vegetation more typical of northern coastal scrub, such as Coyote Brush ( Baccharis pilularis ) overstory with a lower layer of herbaceous vegetation, had greatly increased; but the number of Mountain Beaver burrows had declined to 52% of pre-fire numbers and there was little change in the number of sites occupied between our 2000 and 2005 surveys. With the expected successional changes in thicket structure, Mountain Beaver populations are likely to recover further, but there will probably be considerable variation in how each population stabilizes.

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Gary M. Fellers, Michael Osbourn. 2009. Fire effects on the Point Reyes Mountain Beaver ( Aplodontia rufa phaea ) at Point Reyes National Seashore, 10 years after the Vision Fire. https://doi.org/10.1898/nwn08-08.1

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