The southern yellow bat (''Dasypterus ega'') 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 vespertilionid family is the most diverse and widely distributed of bat famili ...

that belongs to suborder microchiroptera (microbat) in the family Vespertilionidae. It is native to South,

North North is one of the four compass points or cardinal directions. It is the opposite of south and is perpendicular to east and west. ''North'' is a noun, adjective, or adverb indicating direction or geography. Etymology The word ''no ...

and

Central America Central America ( es, América Central or ) is a subregion of the Americas. Its boundaries are defined as bordering the United States to the north, Colombia to the south, the Caribbean Sea to the east, and the Pacific Ocean to the west. ...

, from the

Rio Grande Valley The Lower Rio Grande Valley ( es, Valle del Río Grande), commonly known as the Rio Grande Valley or locally as the Valley or RGV, is a region spanning the border of Texas and Mexico located in a floodplain of the Rio Grande near its mouth. The ...

Texas Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2 ...

in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, t ...

Description

The southern yellow bat is a small bat covered with yellow fur as its name. Generally, females are larger than males. Forearm length of female averages 4% (1.83 mm) greater than that of males.Kurta, A., & Lehr, G. C. (1995). Lasiurus ega. Mammalian Species, 1–7.

Ecology

Range and habitat

Southern yellow bats occur in the southwestern

to northern

and

Uruguay Uruguay (; ), officially the Oriental Republic of Uruguay ( es, República Oriental del Uruguay), is a country in South America. It shares borders with Argentina to its west and southwest and Brazil to its north and northeast; while bordering ...

, with the most austral record being

Buenos Aires Buenos Aires ( or ; ), officially the Autonomous City of Buenos Aires ( es, link=no, Ciudad Autónoma de Buenos Aires), is the Capital city, capital and primate city of Argentina. The city is located on the western shore of the Río de la Plata ...

province,

, at 40° S.Esbérard, C. E. L., & Moreira, S. C. (2006). Second record of Lasiurus ega (Gervais)(Mammalia, Chiroptera, Vespertilionidae) over the south atlantic. Brazilian Journal of Biology, 66(1A), 185–186. They reside in wooded area such as forest, foliage, and palms.Barquez, R. M., & Lougheed, S. C. (1990). New distributional records of some Argentine bat species. Journal of Mammalogy, 261–263. They occasionally occupy other sites that resemble large dead leaves, such as dried corn stalks and thatched roofing Lacki, M. J., Hayes, J. P., & Kurta, A. (Eds.). (2007). Bats in forests: conservation and management. JHU Press. This species roosts in trees and vegetation. In Texas, their preferred roosting sites are the frond "skirts" of both wild and ornamental

palm trees Palm most commonly refers to: * Palm of the hand, the central region of the front of the hand * Palm plants, of family Arecaceae ** List of Arecaceae genera * Several other plants known as "palm" Palm or Palms may also refer to: Music * Palm (b ...

, such as '' Sabal mexicana'' and ''

Washingtonia robusta ''Washingtonia robusta'', known by common name as the Mexican fan palm, Mexican washingtonia, or skyduster is a palm tree native to the Baja California peninsula and a small part of Sonora in northwestern Mexico. Despite its limited native dis ...

''. These are collections of dead fronds against the trunk and provide a favored dark habitat for the bats. Palms are also home to insects, which the bats eat.

Diet

The southern yellow bat is a

nocturnal Nocturnality is an ethology, animal behavior characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite. Nocturnal creatures generally have ...

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 ...

. They forage for one to two hours after sunset on small to medium-sized flying

insect Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (head, thorax and abdomen), three pairs ...

s. They usually feed near their roost, and go no farther than necessary for water.

Behavior

Reproduction

''Lasiurus ega'' copulates before the end of hibernation, but a female ''L. ega'' delays its

ovulation Ovulation is the release of eggs from the ovaries. In women, this event occurs when the ovarian follicles rupture and release the secondary oocyte ovarian cells. After ovulation, during the luteal phase, the egg will be available to be fertilize ...

and stores the sperm for 6 months and fertilizes it later. All reproductive organs involuted following mating in July (early winter) and remained inactive until the following April (autumn).. Crichton, E. G. (2000). Sperm storage and fertilization. Reproductive biology of bats, 295–320. Gestation is continued for 3-3.5 months, and young are born in late. This species is

monoestrous The estrous cycle (, originally ) is the set of recurring physiological changes that are induced by reproductive hormones in most mammalian therian females. Estrous cycles start after sexual maturity in females and are interrupted by anestrous p ...

Flight

The southern yellow bat flies far out to sea and seasonally migrates southward from extreme northern portions of its range.

Migration

In the northern hemisphere, males of ''L. ega'' become scarce between April and June, while females are present year-round, suggesting a migratory strategy. ''L. ega'' shows a tendency to migrate toward the Equator, as described for other species of the genus. Southern yellow bats that migrate along coastlines take shortcuts over water. Many North American migrant bats can be found at a distance of several kilometers from their normal destination during fall and spring migrations, probably having been blown there by wind.CONSTANTINE, D. G., 2003, Geographic translocation of bats: known and potential problems. Emerging Infectious Diseases, 9: 17–21. Both records of ''L. ega'' in the Southern Hemisphere indicate movements at the end of summer and beginning of fall, supporting the theory that at least some animals migrate to avoid cold temperatures. With this second sighting, the probability that both records of this species over the South Atlantic were the result of wind has become less likely.

References

{{Taxonbar, from=Q305707 Southern yellow Southern Yellow Southern Yellow Southern Yellow Southern Yellow Southern Yellow Mammals of Argentina Mammals of Bolivia Mammals of Colombia Mammals of Ecuador Mammals of French Guiana Mammals of Guyana Mammals of Peru Mammals of Paraguay Mammals of Suriname Mammals of Trinidad and Tobago Mammals of Uruguay Mammals of Venezuela Fauna of the Rio Grande valleys Mammals described in 1856 Lasiurini Taxobox binomials not recognized by IUCN