Cave myotis | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Chiroptera |
Family: | Vespertilionidae |
Genus: | Myotis |
Species: | M. velifer |
Binomial name | |
Myotis velifer (J.A.Allen, 1890) | |
The cave myotis (Myotis velifer) is a species of vesper bat (Vespertilionidae) in the genus Myotis .
It is larger than most other bats in the Myotis group, with a forearm of 37 to 44 millimetres (1.5 to 1.7 in). The bat is brown with short ears, and can be distinguished from other large Myotis by a bare patch of skin on its back. Male bats are smaller than females.
It is usually found in caves, although it has been known to inhabit mines and buildings. The largest populations are in southwest Kansas and in Mexico. Groups of over a thousand have been recorded on the ceilings of caves during winter hibernation. [2]
The cave myotis is insectivorous, primarily feeding on moths. To capture prey it uses echolocation, typically hunting one or two hours after sunset. Due to their larger size and well-adapted wings, the cave myotis may forage further from their roost than other "myotis" bats. When insect populations are low in spring and autumn, they decrease their food consumption. Since caves tend to have consistently cooler temperatures which impose energetic strain from maintaining thermoregulation, it is believed that they likely exhibit a combination of behaviors in response, such as consuming greater quantities of food and clustering in order to minimize heat loss. [3] Adult females consume more food than males due to their size. Females also consume more food during lactation and gestation periods. Juveniles are efficient at foraging; they join their adult counterparts aged as young as four weeks. By six to eight weeks, their daily consumption of insects matches that of an adult. Colonies hibernate from mid October until April. Individuals have lifespan of around thirteen years. [4]
Most bat species have a good homing ability, the mechanisms of which are still unknown. Unusually for bats, the cave myotis does not have a good homing instinct. Speculation is that bat species' homing ability relies heavily on olfactory sense and vision. [5]
The gray bat is a species of microbat endemic to North America. It once flourished in caves all over the southeastern United States, but due to human disturbance, gray bat populations declined severely during the early and mid portion of the 20th century. 95% of gray bats now hibernate in only 15 caves. M. grisescens has been listed as federally endangered by the U.S. Fish and Wildlife Service since 1976, and is protected under the Endangered Species Act. Gray bat populations were estimated at approximately 2 million bats around the time they were placed on the Endangered Species list. By the early 1980s populations of gray bats dropped to 1.6 million. With conservation efforts in place, in 2004, gray bat populations were estimated to have reached 3.4 million.
The big brown bat is a species of vesper bat distributed widely throughout North America, the Caribbean, and the northern portion of South America. It was first described as a species in 1796. Compared to other microbats, the big brown bat is relatively large, weighing 15–26 g (0.53–0.92 oz) and possessing a wingspan of 32.5–35 cm (12.8–13.8 in).
The Indiana bat is a medium-sized mouse-eared bat native to North America. It lives primarily in Southern and Midwestern U.S. states and is listed as an endangered species. The Indiana bat is grey, black, or chestnut in color and is 1.2–2.0 in long and weighs 4.5–9.5 g (0.16–0.34 oz). It is similar in appearance to the more common little brown bat, but is distinguished by its feet size, toe hair length, pink lips, and a keel on the calcar.
The pallid bat is a species of bat that ranges from western Canada to central Mexico. It is the sole species of its genus and is closely related to Van Gelder's bat, which is sometimes included in Antrozous. Although it has in the past been placed in its own subfamily (Antrozoinae) or even family (Antrozoidae), it is now considered part of the subfamily Vespertilioninae and the tribe Antrozoini.
The silver-tipped myotis is a species of mouse-eared bat found in a range of lowland habitats in the Americas.
Hodgson's bat, also called the copper-winged bat or black-and-orange myotis, is a species of vesper bat in the genus Myotis, the mouse-eared bats. Favouring mountain forests, it is found throughout Central, Southeast, and East Asia, from Afghanistan to Taiwan. It is about 5 centimetres (2.0 in) long and is distinguished from most other species of bat in this range by its yellowish colouration.
The southeastern myotis is a small bat found throughout the Gulf Coastal Plain and the Lower Mississippi Alluvial Plain of the southeastern United States.
The western mastiff bat, also known as the western bonneted bat, the greater mastiff bat, or the greater bonneted bat, is a member of the free-tailed bat family, Molossidae. It is found in the Western United States, Mexico and South America. This species is the largest bat native to North America, and some of its distinguishing characteristics are its large ears, wings, and forearms. The subspecies Eumops perotis californicus is a species of concern as identified by the U.S. Fish and Wildlife Service. The range of this subspecies is principally southwest desert regions of the United States, along the border with Mexico; however, the range extends as far north on the Pacific coast as Alameda County, California.
The evening bat is a species of bat in the vesper bat family that is native to North America. Hunting at night, they eat beetles, moths, and other flying insects.
The common noctule is a species of insectivorous bat common throughout Europe, Asia, and North Africa.
The eastern small-footed bat is a species of vesper bat. It can be found in southern Ontario and Quebec in Canada and in mountainous portions of the eastern United States from New England to northern Georgia, and westward to northern Arkansas. It is among the smallest bats in eastern North America and is known for its small feet and black face-mask. Until recently, all North American small-footed Myotis were considered to be "Myotis leibii". The western population is now considered to be a separate species, Myotis ciliolabrum. The eastern small-footed bat is rare throughout its range, although the species may be locally abundant where suitable habitat exists. Studies suggest white-nose syndrome has caused declines in their populations. However, 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. Perhaps as a result, the numbers of eastern small-footed bats counted in winter tend to be low and they are relatively variable compared to other species of bats. 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.
The fringed myotis is a species of vesper bat that is found in British Columbia, Mexico, and the western United States.
The long-legged myotis is a species of vesper bat that can be found in western Canada, Mexico, and the western United States.
The Yuma myotis is a species of vesper bat native to western North America.
The California leaf-nosed bat is a species of bat in the family Phyllostomidae. It is found in Mexico and the United States. Its natural habitat is hot deserts.
The little brown bat or little brown myotis is an endangered species of mouse-eared microbat found in North America. It has a small body size and glossy brown fur. It is similar in appearance to several other mouse-eared bats, including the Indiana bat, northern long-eared bat, and Arizona myotis, to which it is closely related. Despite its name, the little brown bat is not closely related to the big brown bat, which belongs to a different genus.
The Virginia big-eared bat is one of two endangered subspecies of the Townsend's big-eared bat. It is found in Virginia, West Virginia, North Carolina, and Kentucky. In 1979, the US Fish and Wildlife Service categorized this as an endangered species. There are about 20,000 left and most of them can be found in West Virginia. The Virginia big-eared bat is the state bat of Virginia.
Myotis septentrionalis, known as the northern long-eared bat or northern myotis, is a species of bat native to North America. There are no recognized subspecies. The northern long-eared bat is about 3–3.7 inches in length, with a wingspan of 9–10 inches. It is distinguishable by its long ears when comparing it to other bats in its genus. This species is commonly found in the northern United States and Southern Canada east of British Columbia. The geographic range includes 37 states.
The California myotis is a species of vesper bat. It is found in British Columbia in Canada, Guatemala, Mexico, and in the western United States, including California.
A maternity colony refers to a temporary association of reproductive female bats for giving birth to, nursing, and weaning their pups. The colonies are initiated by pregnant bats. After giving birth, the colony consists of the lactating females and their offspring. After weaning, juveniles will leave the maternity colony, and the colony itself will break apart. The size of a maternity colony is highly variable by species, with some species forming colonies consisting of ten or fewer individuals, while the largest maternity colony in the world in Bracken Cave is estimated to have over 15 million bats.