Summary ²

Long-tailed weasels, Mustela frenata, are found in southern Canada, the United States, Mexico, Central America, and into parts of northern South America (1). They are present throughout California, excluding the southeastern portion of the state. While long-tailed weasels have the widest range of all mustelids, their population has declined by about 90% in North America in the last 60 years (2). They have been observed in open forest, woodland, shrub, grassland, and agricultural habitats (3).

Long-tailed weasels have slender bodies with long, bushy tails and short legs. Their fur is dark brown on the back and white or yellow on the belly. While the females are smaller than males, the adult body length is between 28 and 42 cm (11–16 in), and the tail length is between 11 and 29 cm (4–11 in) (1). Long-tailed weasels are not social and tend to be aggressive towards intruders, as well as members of their own species in their territory. While long-tailed weasels are mostly nocturnal, they are also known to be active during the day. Their diet mainly consists of small rodents but also includes reptiles, birds, and fruits. Mating occurs in the summer and litters are raised in nests often located in the burrows of other mammals (3).

Coal Oil Point Reserve ²

At Coal Oil Point Reserve, long-tailed weasels occupy grassland, coastal scrub, and woodland habitats. Long-tailed weasels are uncommon at the reserve. They are rarely seen by the passer-by but are present on the reserve year-round.

References ²

1. Newell, T.L. (2002). Mustela frenata. Animal Diversity Web. https://animaldiversity.org/accounts/Mustela_frenata/
2. Jachowski, Kays, R., Butler, A., Hoylman, A. M., & Gompper, M. E. (2021). Tracking the decline of weasels in North America. PloS One, 16(7), e0254387–.
3. California Wildlife Habitat Relationships System. (1988-1990). Life history account for Long-tailed weasel. California Department of Fish and Wildlife. https://wildlife.ca.gov/Data/CWHR/Life-History-and-Range

Sources and Credits

1. (c) davidcooksy, some rights reserved (CC BY-NC)
2. (c) copr, some rights reserved (CC BY-SA)

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