Thermal Characteristics of Pacific Marten Habitat and Rest Structures

$730 Awarded to Marie Martin, University of Wisconsin-Madison in 2017 to study Pacific martens.

Many carnivores have suffered pervasive and significant declines in distribution and abundance.  Additionally, the weight of climate change and associated habitat alterations appears to fall disproportionately on montane regions.  This has led to relatively greater impacts on montane carnivores and associated prey communities, as they are sensitive to declining snowpack and changing temperatures.  One such carnivore, the Pacific marten (Martes caurina) may be particularly sensitive due to its long, slender body, short coat, and relatively little body fat.  Previous research has shown that forest management and disturbance change the way martens perceive their surroundings, causing them to move more quickly and erratically.  With conservation grant funding by Sequoia Park Zoo, Marie Martin, a Master’s degree candidate at the University of Wisconsin-Madison, showed that increasing speed of movement and shifting climatic conditions increased the energetic expenditures of martens.  She also found that ambient temperature was significantly more stable in complex forest patches and tree cavities.  Further, tree cavities appeared to have significant insulative properties – when it was very warm, cavities stayed cooler than ambient temperature and when it was very cold, cavities stayed warmer than ambient temperature.  These results suggested that martens may be able to offset the costs of extreme temperatures by moving through complex, densely vegetated forest patches or by resting in tree cavities.