Silver-haired bat
{{Short description|Species of bat}}
{{speciesbox
| image = Silver-haired bat.JPG
| image_caption = Male captured in the Ozark National Scenic Riverways in 2010.
| status = LC
| status_system = IUCN3.1
| display_parents = 3
| genus = Lasionycteris
| parent_authority = Peters, 1866
| species = noctivagans
| authority = (Le Conte, 1831)
| synonyms =
| range_map = Distribution of Lasionycteris noctivagans.png
| range_map_caption = Distribution of the silver-haired bat (2009)
}}
The silver-haired bat (Lasionycteris noctivagans) is a solitary migratory species of vesper bat in the family Vespertilionidae and the only member of the genus Lasionycteris.{{MSW3 Chiroptera | id = 13802336 | page = 499}}
Etymology
The species name translates as night-wandering, referring to the nocturnal behavior of bats.
Description
This medium-sized bat is predominantly black (including the wings, ears, interfemoral membrane, and fur) with white-tipped hairs. The basal upper half of its tail membrane is densely furred. This gives the bat a frosted appearance and its common namesake. This species has a flattened skull with a broad rostrum.Kunz, T. 1982. Lasionycteris noctivagans. American Society of Mammalogists. No 172 pp. 1-5. {{doi|10.2307/3504029}} {{JSTOR|3504029}} This species weighs around 8–12 g, has a total length of ~100 mm, a tail length of 40 mm, and a forearm length of 37–44 mm.{{cite web |url=http://www.nsrl.ttu.edu/tmot1/lasinoct.htm |title=Silver-haired Bat |publisher=The Mammals of Texas – Online Edition}}
Distribution and habitat
Lasionycteris noctivagans is found in Bermuda, Canada, Mexico, and the United States. This forest inhabitant is known to occur from southeastern Alaska in summer to northeastern Mexico in winter Cryan, P.M. 2003. Seasonal distribution of migratory tree bats (Lasiurus and Lasionycteris) in North America. Journal of Mammalogy 84(2): 579-593. and is found in arid habitats at low elevations during seasonal migrations. In Missouri, reproduction occurs in the northern dissected plains region, but reproductive females are believed to be absent from the southern Ozark highlands in the summer.
They often roost in tree cavities or in bark crevices on tree trunks, especially during migration. Their unique coloration makes them blend in with their roosting environment.
[https://www.cdc.gov/rabies/bats/contact/index.html Coming in Contact with Bats]. Centers for Disease Control and Prevention National Center for Emerging and Zoonotic Infectious Diseases (NCEZID) Division of High-Consequence Pathogens and Pathology (DHCPP). However, some individuals seem to overwinter in buildings, which may allow them to spend the winter in places that would otherwise be too cold for them.{{Cite journal|last1=Kurta|first1=Allen|last2=Auteri|first2=Giorgia G.|last3=Hofmann|first3=Joyce E.|last4=Mengelkoch|first4=Jean M.|last5=White|first5=J. Paul|last6=Whitaker|first6=John O.|last7=Cooley|first7=Thomas|last8=Melotti|first8=Julie|date=2018-04-17|title=Influence of a Large Lake on the Winter Range of a Small Mammal: Lake Michigan and the Silver-Haired Bat (Lasionycteris noctivagans)|journal=Diversity|language=en|volume=10|issue=2|pages=24|doi=10.3390/d10020024|doi-access=free|url=http://pdfs.semanticscholar.org/54bd/fa828629233f3c08002cf4d257f18d1c7a31.pdf}}
Life history
Copulation of tree bats is likely initiated during flight. After mating, tree bats hibernate alone in tree cavities, bark crevices, beneath leaf litter, or in the twilight zone of caves. Gestation typically takes 50–60 days, so that parturition of pups occurs in early summer when insect availability is high.Hayssen, V., A. van Tienhoven, and A. van Tienhoven. 1993. Asdell’s patterns of mammalian reproduction. Comstock Publ. Assoc., Ithaca, NY. Pups are born breech by presentation, and the mother consumes the placenta Kurta, A.D, and T.H. Kunz. 1987. Size of bats at birth and maternal investment during pregnancy. Symposia of the Zoological Society of London 57:79–106. Females typically give birth to two offspring, with an even sex ratio.
Diet and foraging behavior
Silver-haired bats consume primarily soft-bodied insects, such as moths, but will also take spiders and harvestmen. This species will forage low, over both still and running water, and also in forest openings. Silver-haired bats are slow but maneuverable flyers that typically detect prey a short distance away.Barclay, R.M.R. 1985. Long-versus short-range foraging strategies of hoary (Lasiurus cinereus) and silver-haired (Lasionycteris noctivagans) bats and the consequences for prey selection. Canadian Journal of Zoology. 63(11):2507–2515. {{doi|10.1139/z85-371}}
Conservation threats
In addition to the hoary bat (Lasiurus cinereus) and eastern red bat (Lasiurus borealis), the silver-haired bat is one of the three tree bat species most commonly killed at wind energy facilities (over 75% of the mortalities).{{cite journal|vauthors=Arnett EB, Brown WK, Erickson WP, Fiedler JK, Hamilton BL, Henry TH, Jain A, Johnson GD, Kerns J, Koford RR, Nicholson CP, O'Connell TJ, Piorkowski MD, Tankersley RD|year=2008|display-authors=6|title=Patterns of fatality of bats at wind energy facilities in North America|journal=Journal of Wildlife Management|volume=72|issue=1|pages=61–78|doi=10.2193/2007-221}}
The causative agent of white-nose syndrome, Pseudogymnoascus destructans, has been detected on a silver-haired bat in Delaware, although this species does not suffer the same mass mortalities observed in smaller-bodied hibernating North American cave bats.{{cite web |url=http://batcon.org/index.php/what-we-do/white-nose-syndrome/subcategory/466.html |title=White-nose Syndrome |access-date=2014-03-03 |url-status=dead |archive-url=https://web.archive.org/web/20140310134521/http://batcon.org/index.php/what-we-do/white-nose-syndrome/subcategory/466.html |archive-date=2014-03-10 }}
Like all bats, silver-haired bats are vulnerable to population threats because of their inherently low reproductive rate.Barclay, R.M.R., J. Ulmer, C.J.A. MacKenzee, M.S. Thompson, L. Olson, J. McCool, E.E. Cropey, and G. Poll. 2004. Variation in the reproductive rate of bats. Canadian Journal of Zoology. 82, 688–693. {{doi|10.1139/z04-057}}
Rabies
Most bats do not have rabies; however, most recent human rabies deaths have been due to a strain of rabies associated with this species. In 2015, a Wyoming woman woke up to a bat on her shoulder later to be identified as a silver-haired bat. She presented to the emergency department several weeks later with ataxia, dysphagia, and weakness. After over a week of diagnostic workup, she was determined to have the rabies virus, which was traced to the bat incident. She died several days later.{{cite web |last1=Harrist |first1=A |last2=Styczynski |first2=A |last3=Wynn |first3=D |title=Human Rabies — Wyoming and Utah |url=https://www.cdc.gov/mmwr/volumes/65/wr/mm6521a1.htm |website=CDC |publisher=MMWR Morb Mortal Wkly |access-date=25 June 2021 }}