Are There Still Wolverines in California?

Wolverines are present in California, though they are exceptionally rare and their continued presence is a focus of scientific observation. While historically found throughout the state’s mountainous regions, these animals experienced a decline. California currently lacks an established breeding population of wolverines. Recent detections have provided insights, prompting ongoing efforts to understand and support this elusive species. In California, wolverines are classified as a threatened species.

Past Presence in California

Wolverines once roamed across the mountainous terrain of California. Their historical range extended from Mount Shasta in the north down to Monache Meadows in Tulare County. However, their population experienced a rapid decline, leading to their near disappearance from the state by 1922. This reduction was primarily a result of trapping, hunting, and other human activities. One of the last documented historical sightings occurred in February 1922 in Mono County; genetic analysis of historical wolverine specimens from California indicates that these animals were genetically distinct and isolated from other North American populations for an extended period.

Current Sightings and Habitats

Following their historical decline, a wolverine was detected in California between 2008 and 2018, first appearing in the Tahoe National Forest; this individual was identified through DNA analysis as having likely traveled from Idaho’s Sawtooth Range. More recently, in May 2023, multiple sightings of a single wolverine were confirmed in the Eastern Sierra Nevada mountains; these observations occurred across Inyo National Forest, spanning Inyo and Mono counties, and within Yosemite National Park in Tuolumne County. The California Department of Fish and Wildlife, in collaboration with U.S. Forest Service experts, confirmed the animal’s identity by analyzing images and videos that showcased its size, coloration, and movement patterns. Given the typical wolverine lifespan of 12 to 13 years, the wolverine sighted in 2023 is believed to be a different individual from the one observed between 2008 and 2018. While wolverines are widely distributed in Canada and Alaska, smaller populations exist in the Rocky and Cascade mountains, suggesting potential dispersal routes into California.

Factors Contributing to Their Rarity

Wolverines are naturally solitary animals that require expansive, undisturbed high-alpine habitats; they exist at inherently low population densities, which makes sightings uncommon. A male wolverine’s home range can exceed 620 square kilometers (240 square miles), often overlapping with the smaller ranges of several females; they typically favor high-elevation coniferous forests and alpine tundra. Female wolverines create their dens by burrowing into deep snow, using these sites until mid-May for raising their young. The ongoing rarity of wolverines in California is influenced by climate change, which leads to reduced and earlier melting snowpack, directly impacting these vital denning areas. Habitat loss and fragmentation, resulting from human development, also restrict their available range.