ImportanceThe Cascade Red Fox is a Washington Candidate Species for protection and Natural Heritage Critically Imperiled Species. It is endemic to Washington where it is restricted to the upper mountain forest, subalpine parkland, and alpine meadows of the Cascade Range. The ancestors of this subspecies of red fox migrated across the Bering Landbridge into North America during the Illinoian glaciation over 300,000 years ago. During the most recent (Wisconsin) glaciation, the foxes were pushed south of the icesheets into ice-free forest refuges in what is now North America’s midwest. There, they presumably adapted to the colder, glacial climate, which lasted for approximately 100,000 years and they became genetically and morphologically distinct. When the Wisconsin icesheets receded, the foxes migrated into the mountains where conditions were similar to the glacial period. These foxes prey on small mammals and birds unique to the mountains and thus have an ecology distinct from lowland red foxes. The volcanoes of the Cascade Range appear to act as islands of habitat in the sky for small and isolated Cascade Red Fox populations. The low-elevation forest may as well be the ocean and it is unknown whether the foxes move between these sky islands. Recent surveys for the Cascade red fox and other carnivores suggest a precipitous loss of population abundance and distribution of this unique carnivore.
This decline may be caused by changes to their mountain home including habitat loss and alteration due to climate change, widespread mid-elevation timber removal, and increased winter recreation that provides pathways into alpine areas for less snow- adapted predators and competitors such as the coyote and non-native, lowland red foxes. Many species that live at high elevation in the Pacific Northwest, such as the Wolverine and Pika, are of particular conservation concern due to their unique evolutionary histories and their sensitivity to climate change. They serve as indicators of future changes that will eventually affect more tolerant species and as such, make good models for conservation under changing climatic conditions. The Cascade red fox is such species.