Eastern small-footed myotis

Appearance

In most individuals, the ears, wings and interfemoral membrane (the membrane between the legs and tail) are dark and contrast starkly with the lighter colored fur on the rest of the body. The fur on the dorsal side of their body is dark at the roots, and fades to a light brown at the tips, that gives the bats a signature shiny, chestnut-brown appearance. It is among the smallest bats in eastern North America and is known for its small feet and black face-mask.

The eastern small footed bat is between 65 and 95 millimeters in length, has a wingspan of 210 to 250 millimeters, and weighs between 4 and 8 grams (with 4.0 to 5.25 grams being typical). The keeled calcar combined with their small forearms (less than 34 mm in length) can be used to distinguish them from all other Myotis in eastern North America.

Range and habitat

The range of this species includes northern Arkansas and southern Missouri, east to the Appalachian Mountains and Ohio River basin, south into northern Georgia, and north into New England, southern Ontario and Quebec. Distribution is spotty within their entire range, and they are considered to be uncommon. Most observations have been from mountainous areas from 240 to 1125 meters in elevation, where exposed rock formations are more common.

Once awake bats begin to expend energy and deplete critical fat reserves needed to survive winter.

Pins are Wikidata “endemic to” fields. Orange dots, when present, are GBIF occurrence tiles — survey bias included.

Diet and breeding

Eastern small-footed bats are believed to feed primarily on flying insects such as beetles, moths, and flies and are capable of filling their stomachs within an hour of eating. Moths compose nearly half of their diet, and they forage primarily on soft-bodied prey.

It is believed that the avoidance of hard prey is due to their small, delicate skulls. During the time of breeding, large number of bats come together in a behavior called "swarming". All bats of this genus are polyandrous, meaning they mate with multiple partners throughout the mating period.

In crisis

The western population is now considered to be a separate species, Myotis ciliolabrum. Studies suggest white-nose syndrome has caused declines in their populations. Even so, most occurrences of this species have only been counted within the past decade or two and are not revisited regularly, making their population status difficult to assess.

Additionally, most bat populations in the eastern U.S. Have been monitored using surveys conducted in caves and mines in the winter, but eastern small-footed bats hibernate in places that make them unlikely to be encountered during these surveys. Many biologists believe the species is stable, having declined little in recent times, but that it is vulnerable due to its relatively restricted geographic range and habitat needs.

Eastern small-footed myotis is Endangered on this catalog because that is the IUCN category stored on Wikidata. Confirm the official criteria and any later count on iucnredlist.org.

Sources

Written for this catalog from the English Wikipedia article on Eastern small-footed myotis, Wikidata item Q1832366. Family and order context is original field-guide writing about the group, not a copied assessment of this one species. Wikipedia text is CC BY-SA. Not an IUCN assessment. Counts, when quoted, can change — confirm them on the recovery programme and on iucnredlist.org.