The little forest bat (''Vespadelus vulturnus'') is a species of vesper bat in the family Vespertilionidae. It is found only in south-eastern

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

, including Tasmania. It is a tiny bat often weighing less than (males in some areas weigh as little as ). It is sometimes referred to as Australia's smallest mammal, although the Northern or Koopmans Pipistrelle, ''

Pipistrellus westralis The northern pipistrelle (''Pipistrellus westralis''), also known as Koopman's or the mangrove pipistrelle, is a species of vesper bat found only in Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, s ...

'', is possibly smaller, weighing on average around . It is the smallest bat in Tasmania

Biology and ecology

The little forest bat is one of the most commonly observed bats in south-eastern Australia, it is found in a variety of habitats including Eucalypt woodlands and forests as well as in rural, semi-rural and some urban areas. It is an

insectivore A robber fly eating a hoverfly An insectivore is a carnivorous animal or plant that eats insects. An alternative term is entomophage, which can also refer to the human practice of eating insects. The first vertebrate insectivores wer ...

and roosts in

tree hollows A tree hollow or tree hole is a semi-enclosed cavity which has naturally formed in the trunk or branch of a tree. They are found mainly in old trees, whether living or not. Hollows form in many species of trees, and are a prominent feature of nat ...

. Females become sexually mature in their first year and males in their second year. It is assumed the males wake from torpor and mate with the females during winter. A single pup is born in spring (October–November).

Identification

The little forest bat is very small with pale grey or brownish fur. The tragus is usually white and the skin on the face, feet and forearm is usually pinkish. Adults usually weigh between and the forearm is usually less than (mean =). The wingspan can range up to and the body length is up to . Females are slightly larger than males. The little forest bat is very similar in appearance and often confused with a number of other bats that it co-occurs with (

sympatric In biology, two related species or populations are considered sympatric when they exist in the same geographic area and thus frequently encounter one another. An initially interbreeding population that splits into two or more distinct species sh ...

) including

Vespadelus regulus The southern forest bat (''Vespadelus regulus'') is a vesper bat found in Australia. Taxonomy A species of '' Vespadelus'', of the diverse and common micro-bats, bats assigned as either suborder Yangochiroptera or Microchiroptera. The descrip ...

Vespadelus darlingtoni The large forest bat (''Vespadelus darlingtoni'') is a common vesper bat found in southeast Australia, Tasmania, and Lord Howe Island. Taxonomy The first description was published by G. M. Allen in 1933. The specimen described was obtained by ...

, Vespadelus baverstocki,

Vespadelus troughtoni The eastern cave bat or Troughton's forest bat (''Vespadelus troughtoni'') is a species of vesper bat Vespertilionidae is a family of microbats, of the order Chiroptera, flying, insect-eating mammals variously described as the common, vesper, ...

Vespadelus pumilus The eastern forest bat (''Vespadelus pumilus'') is a species of vesper bat Vespertilionidae is a family of microbats, of the order Chiroptera, flying, insect-eating mammals variously described as the common, vesper, or simple nosed bats. The ...

and

Scotorepens greyii The little broad-nosed bat (''Scotorepens greyii'') (pronounced skoh’-toh-rep’-enz grey’-ee-ee’) translates to "Grey’s darkness creeper". Sometimes called Grey’s broad-nosed after the third governor of South Australia, Sir John Edward ...

. Live bats can be differentiated from these species using a combination of size, relative finger bone lengths and, in males, penis shape. Males have a distinctly shaped

baculum The baculum (also penis bone, penile bone, or ''os penis'', ''os genitale'' or ''os priapi'') is a bone found in the penis of many placental mammals. It is absent from the human penis, but present in the penises of some primates, such as the ...

. There is some variation in the morphology of this species across its range, with some taxonomists suggesting there may be

cryptic species In biology, a species complex is a group of closely related organisms that are so similar in appearance and other features that the boundaries between them are often unclear. The taxa in the complex may be able to hybridize readily with each oth ...

that have not yet been identified within the species.

Echolocation call

The echolocation call of the little forest bat is regionally variable, in New South Wales the characteristic frequency of search phase calls is between 42.5 and 53

kilohertz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one h ...

depending on the region where it is found. This is more than double the maximum frequency of the human hearing range and cannot be heard without the assistance of a bat detector.

References

{{Taxonbar, from=Q305691 Bats of Australia Vespadelus Mammals of Tasmania Mammals of South Australia Mammals of New South Wales Mammals of Victoria (Australia) Mammals described in 1914 Taxa named by Oldfield Thomas Taxonomy articles created by Polbot Vertebrates of Tasmania