{{Short description|Species of bat}} {{Speciesbox | name = Southern yellow bat | status = LC | status_system = IUCN3.1 | status_ref= <ref>{{cite iucn |author=Barquez, R. |author2=Diaz, M. |date=2016 |title=''Lasiurus ega'' |article-number=e.T11350A22119259 |doi=10.2305/IUCN.UK.2016-3.RLTS.T11350A22119259.en |access-date=27 December 2022}}</ref> | genus = Lasiurus | species = ega | authority = Gervais, 1856 | range_map = Lasiurus ega map.svg | image = Naturalis Biodiversity Center - RMNH.MAM.17371.b ven - lasiurus Ega Ega - skin.jpeg }}

The '''southern yellow bat''' ('''''Lasiurus ega''''') is a species of vesper bat that belongs to suborder microchiroptera (microbat) in the family Vespertilionidae. It is native to South, North and Central America, from the Rio Grande Valley of Texas in the United States to Argentina.

==Description== The southern yellow bat is a small bat covered with yellow fur as its name indicates. Generally, females are larger than males. Forearm length of female averages 4% (1.83&nbsp;mm) greater than that of males.<ref name="kurta1995">Kurta, A., & Lehr, G. C. (1995). Lasiurus ega. Mammalian Species, 1–7.</ref>

==Ecology==

===Range and habitat=== Southern yellow bats occur in the southwestern United States to northern Argentina and Uruguay, with the most austral record being Buenos Aires province, Argentina, at 40° S.<ref name="Esbérard2006">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.</ref> They reside in wooded area such as forest, foliage, and palms.<ref name=Barquez1990>Barquez, R. M., & Lougheed, S. C. (1990). New distributional records of some Argentine bat species. Journal of Mammalogy, 261–263.</ref> They occasionally occupy other sites that resemble large dead leaves, such as dried corn stalks and thatched roofing <ref name=Lacki2007>Lacki, M. J., Hayes, J. P., & Kurta, A. (Eds.). (2007). Bats in forests: conservation and management. JHU Press.</ref> This species roosts in trees and vegetation.<ref>{{cite web |url=https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.104929/Lasiurus_ega |title=''Lasiurus ega'' – Southern Yellow Bat |work=InfoNatura |publisher=NatureServe |access-date=2009-07-04}}</ref> In Texas, their preferred roosting sites are the frond "skirts" of both wild and ornamental palm trees, such as ''Sabal mexicana'' and ''Washingtonia robusta''. 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.<ref>{{cite web |url=http://www.fhwa.dot.gov/environment/wildlifeprotection/index.cfm?fuseaction=home.viewArticle&articleID=55 |archive-url=https://web.archive.org/web/20030625165616/http://www.fhwa.dot.gov/environment/wildlifeprotection/index.cfm?fuseaction=home.viewArticle&articleID=55 |archive-date=June 25, 2003 |first=Juan |last=Alcazar |title=Not trimming palm fronds saves baby bats |work=Keeping It Simple: Easy Ways to Help Wildlife Along Roads |publisher=Federal Highway Administration, United States Department of Transportation |date=2003-04-25 |access-date=2009-07-04}}</ref>

===Diet=== The southern yellow bat is a nocturnal insectivore. They forage for one to two hours after sunset on small to medium-sized flying insects. 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 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).<ref name=Crichton2000>. Crichton, E. G. (2000). Sperm storage and fertilization. Reproductive biology of bats, 295–320.</ref> Gestation is continued for 3-3.5 months, and young are born in late. This species is monoestrous.<ref name="kurta1995"/>

===Flight=== The southern yellow bat flies far out to sea and seasonally migrates southward from extreme northern portions of its range.<ref name="kurta1995"/>

===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.<ref name="kurta1995"/> ''L. ega'' shows a tendency to migrate toward the Equator, as described for other species of the genus.<ref name="kurta1995"/> 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.<ref name=CONSTANTINE2003>CONSTANTINE, D. G., 2003, Geographic translocation of bats: known and potential problems. Emerging Infectious Diseases, 9: 17–21.</ref> 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.<ref name="Esbérard2006"/>

==See also== *Bats of the United States

== References == {{Reflist}}

{{Vespertilionidae|V.|L.}} {{Taxonbar|from=Q305707}}

Southern yellow Southern Yellow Southern Yellow Southern Yellow Southern Yellow Southern Yellow Category:Mammals of Argentina Category:Mammals of Bolivia Category:Mammals of Colombia Category:Mammals of Ecuador Category:Mammals of French Guiana Category:Mammals of Guyana Category:Mammals of Peru Category:Mammals of Paraguay Category:Mammals of Suriname Category:Mammals of Trinidad and Tobago Category:Mammals of Uruguay Category:Mammals of Venezuela Category:Fauna of the Rio Grande valleys Category:Mammals described in 1856 Category:Lasiurus