California Myotis – State Wildlife Action Plan

California Myotis

California Myotis on tree
A California myotis (Myotis californicus) on the bark of a tree in the Rogue River National Forest, Oregon. Photo Credit: Michael Durham, https://www.flickr.com/photos/oregonwild/

The California myotis is one of the smallest insectivorous bats in the United States; adults weigh 3-5 grams and a have wingspan of 22-23 cm. The hind feet of California myotis are small with a prominently keeled calcar. Their fur is relatively long and dull, ranging in color from dark brown in the Pacific Northwest to a pale yellowish-orange in more arid regions. Although females tend to be larger than males on average, there is no apparent sexual dimorphism. With relatively low wing loading and low aspect ratio, these bats have slow flight yet high maneuverability, which helps them hunt in a wide variety of habitats from forests to semi-deserts. Within these habitats, the California myotis forages along forest edges, over water, and high above ground level in open spaces. California myotis use a variety of broadband (frequency-modulated) echolocation signals, utilizing short, long, steep or shallow calls to detect prey and physical structures.

Overview

  • Species Common Name California Myotis
  • Species Scientific Name Myotis californicus
  • State Listing Status Sensitive

Ecoregions

    Special needs

    This species is generally associated with forests. California myotis use large snags for day roosts. They are occasionally found night-roosting under bridges.

    Limiting factors

    California myotis are patchily distributed and have low reproductive rates. Availability of large snags for roosting may be a limiting factor.

    Conservation actions

    • Maintain and create large snags during forest management activities.
    • Complete bridge replacement and maintenance when bats are absent.
    • Continue white-nose syndrome surveillance.
    • Follow most recent decontamination protocols to prevent spread of the fungus that causes white-nose syndrome, Pseudogymnoascus destructans

    Key reference or plan

    North American Bat Monitoring Program in the Pacific NW. Read here