Eastern Small-footed Bat

M leibii J Albert Bauer 2010

Photo Credit: Sandy Dobbyn

Myotis leibii

Status:

  • COSEWIC –n.a
  • COSSARO – Endangered

Description:

  • True to its name, the Eastern Small-footed Bat’s (myotis) feet are only 7-8 mm long, less than 1cm!
  • This bat is one of the smallest and rarest bats in North America, only about 8 cm long and just 4-5 grams (roughly the weight of a nickel).
  • Their wing span is 21-25 cm.
  • Males and females are similar in color and size.
  • This bat’s fur has black roots and shiny light brown tips for an overall yellow-brown appearance. Its face mask, ears and wings are black, and underside is gray-brown.

Food:

  • A nocturnal hunter, the eastern small footed bat hunts for primarily flying insects including beetles, mosquitos, moths, and flies.

Habits & Reproduction:

  • Mating is usually in late summer or fall but occasionally happens in winter.
  • Both males and females have multiple mates.
  • Females give birth once a year between May and July. When they give birth they’re often found in large groups of mostly females called maternity colonies.
  • At birth Eastern Small-footed Bats weigh 20 to 35% of their mother’s weight. This is large for a newborn explaining why the mother has one at a time.
  • Eastern Small-footed Bats can live 6-12 years in the wild.

Habitat:

  • In the spring and summer, Eastern Small-footed Bats roost in various habitats such as rock crevices, rock outcrops, tunnels, buildings, underneath bridges, caves, mines, or tree hollows.
  • In summer, these bats often change their roosting locations every day.
  • In winter, these bats often hibernate in the coldest parts of shallow (less than 150 meters long) caves and mines. They will return to the same hibernation site every year.

Threats:

  • White-nose Syndrome (WNS) has led to catastrophic declines of bat populations in north-eastern North America. WNS is caused by a fungus that likely originated in Europe. It grows in humid, cold environments, typical of caves where bats hibernate.
  • It was first identified in a cave near Albany, New York in 2006. By 2010, WNS was confirmed in Ontario. The mortality rates at infected hibernation sites in Ontario, Quebec and New Brunswick are over 80%.
  • WNS is expanding in Canada at average rate range of 200-400km/yr. If the spread of WNS continues at the current rate, the entire Canadian population would likely be impacted within 11-22 years.
  • For more information: http://www.ontario.ca/environment-and-energy/white-nose-syndrome-bats

Conservation Actions:

  • Please report any unusual bat activity such as flying outside in daytime or deaths to the Ministry of Natural Resources and Forestry at 800-667-1940.
  • You can help reduce the spread. Do not enter non-commercial caves and abandoned mines where bats may be present.

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