The Humboldt marten, a rare, ferret-sized carnivore, is currently listed as threatened under the Endangered Species Act. Weighing about two pounds, the subspecies of the Pacific marten was nearly wiped out by the fur trade and old-growth logging. It was thought to be extinct until it was rediscovered during a wildlife survey in the mid-1990s.
Innovative population tracking
Sean Matthews, wildlife ecologist at Oregon State University, is leading efforts to determine whether the small, isolated marten populations are stable or declining. His team collects hair samples for genetic analysis, placing PVC baited with chicken and fitted with glue strips in the forest.
DNA analysis allows researchers to identify individual martens, which Matthews calls "adorable," and determine their sex, providing a baseline for long-term population monitoring. Matthews said the work moves beyond simply mapping where martens live to estimating how many remain.
Martens are closely associated with high-elevation forested ridgetops and lower-elevation coastal ravines. They depend on forests with a complex, layered structure — including large trees, downed logs and dense vegetation — to survive and evade predators such as bobcats.
Skilled climbers, they move through the canopy and can descend trees headfirst to escape danger.
Clearer lens
During a three-month study in 2022, researchers used the hair snares and remote cameras to survey about 150 square miles east of Klamath, California. Genetic analysis identified 46 martens, 28 males and 18 females.
Martens were most abundant along high-elevation forested ridgetops with consistent winter snowpack and in lower-elevation ravines and riparian areas within coastal forests.
The findings help inform conservation and land-use decisions affecting the coastal marten, a member of the weasel family. Remaining populations in Northern California and Southern Oregon continue to face threats from habitat loss, rodenticides, vehicles and disease.
Land managers, including the Yurok Tribe and public and private landowners, are using the findings to identify areas with higher marten densities and apply lighter-touch wildfire fuel treatments.
Researchers said this approach reduces fire risk while preserving critical habitat and supporting climate-resilient forests, helping the Humboldt marten expand its narrow coastal range.
Guest
- Sean Matthews
