HOARY BAT
Lasiurus cinereus
(Palisot de Beauvois, 1796)


laz-E-ur-us sin-ar-E-us




Color photos by Robert M. Timm.
Color photos by Robert M. Timm.
Image © by Greg Sievert.
Image © by Greg Sievert.
Image © by Greg Sievert.
Image © by Greg Sievert.

Description:
The hoary bat is large (by North American bat standards) and has a heavily furred tail membrane. It has short, rounded ears edged with black. The pelage is "hoary" (frosted) in appearance, resulting from individual hairs being black at their base, followed by a yellow band, a brown band, and a white tip. The wings are long and pointed. The dental formula is incisors 1/3, canine 1/1, premolars 2/2, molars 3/3.
Lasiurus cinereus is not apt to be confused with any other bat in Kansas because of its large size and distinctive appearance.

Distribution:
The three subspecies of Hoary Bat have disjunct distributions. One subspecies occurs in North America from northern Canada to Guatemala. Another subspecies occurs in South America. The third subspecies occurs only on the Hawaiian islands, where it is the only native terrestrial mammal. Hoary bats are migratory, spending the winter in Mexico. In spring, they return northward in a gender-segregated manner, most males into the western United States and Canada and most females into the eastern United States and Canada. Kansas, located centrally, has both genders but females are said to be about twice as abundant as males. Collection data indicate that the earliest individuals arrive in Kansas in March and the latest individuals leave Kansas in October.
Fossils of this species have been found in Pleistocene deposits in Kansas, New Mexico, Texas, and Mexico.

(, Museum Voucher) (, Observation) (, Literature Record)
Open icons are questionable records; Click on a marker to view details.
  • Occurrence Summary:  
  • 134 Total Records 
  • 126 Museum Vouchers 
  • 8 Other Observations 
Some county occurrences indicated below may be too imprecise to map above.
County Breakdown: County Name (# occurrences):
Anderson (1); Barber (3); Barton (1); Bourbon (1); Cheyenne (1); Crawford (1); Dickinson (1); Douglas (58); Ellis (12); Finney (1); Franklin (1); Graham (1); Greenwood (1); Jackson (1); Jewell (3); Leavenworth (1); Lyon (10); Marshall (2); Meade (3); Miami (1); Mitchell (1); Morton (4); Ness (1); Pawnee (1); Phillips (1); Pottawatomie (2); Pratt (3); Reno (1); Riley (2); Rooks (3); Sedgwick (1); Shawnee (1); Stanton (6); Sumner (1); Woodson (1);

Natural History:
Like the related red bat, the hoary bat is solitary and roosts in trees. Roosts are in either coniferous or deciduous trees, generally from 5 to 7 m above the ground, and visible only from directly below the roost. Hoary bats must fall from the roost to obtain enough airspeed to support flight. They leave the roost when it is completely dark and fly birdlike with alternating wing flaps and glides. They often fly higher than other species. They are protective of their foraging areas and may drive other bats away.
Adults may attain the following dimensions: total length 133-150 mm; length of tail 46-65 mm; length of hind foot 11-14 mm; length of ear 17-20 mm; weight 19.5-34.5 g. Numerous authors have speculated what longevity for this species is, but there do not seem to be any conclusive data.
Hoary bats eat more moths than other insects, including beetles, flies, grasshoppers, termites, dragonflies, and wasps.
Because of its strong flight, the hoary bat is capable of avoiding predation by all but the fastest raptors. There is one report of predation by an American kestral. On the other hand, roosting in trees facilitates predation by many predators, including snakes. Moreover, females with young may be blown from their roosts during storms and face predation by cats and dogs before they can return to the roost. This species has the reputation of becoming snagged on barbed wire, possibly because it flies too fast to avoid fences. Finally, this is one of the three species (the others being the eastern red bat and the silver-haired bat) that are killed most often by wind turbines in wind farms.
Like the related red bat, the hoary bat is solitary and roosts in trees. Roosts are in either coniferous or deciduous trees, generally from 5 to 7 m above the ground, and visible only from directly below the roost. Hoary bats must fall from the roost to obtain enough airspeed to support flight. They leave the roost when it is completely dark and fly birdlike with alternating wing flaps and glides. They often fly higher than other species. They are protective of their foraging areas and may drive other bats away.
Adults may attain the following dimensions: total length 133-150 mm; length of tail 46-65 mm; length of hind foot 11-14 mm; length of ear 17-20 mm; weight 19.5-34.5 g. Numerous authors have speculated what longevity for this species is, but there do not seem to be any conclusive data.
Hoary bats eat more moths than other insects, including beetles, flies, grasshoppers, termites, dragonflies, and wasps.
Because of its strong flight, the hoary bat is capable of avoiding predation by all but the fastest raptors. There is one report of predation by an American kestral. On the other hand, roosting in trees facilitates predation by many predators, including snakes. Moreover, females with young may be blown from their roosts during storms and face predation by cats and dogs before they can return to the roost. This species has the reputation of becoming snagged on barbed wire, possibly because it flies too fast to avoid fences. Finally, this is one of the three species (the others being the eastern red bat and the silver-haired bat) that are killed most often by wind turbines in wind farms.
Hoary bats probably breed during winter. The sperm remain dormant in the female until ovulation in the spring. After a gestation period of uncertain length, two young (rarely three or four even though four nipples are present in the female) are born blind and hairless. The young remain with the female after they are able to fly at the age of 4 or 5 weeks.

Occurrence Activity:
Remarks:
The subspecies that occurs in Kansas (and throughout North America) is Lasiurus cinereus cinereus.

Bibliography:
1952 Cockrum, E. L. Mammals of Kansas. Univ. Kansas Publ. Mus. Nat. Hist. 7:1-303. ():
1954 Baker, R. H. A hoary bat from northwestern Kansas. Trans. Kansas Acad. Sci., 57:196. ():
1967 Jones, J. K. Jr., E. D. Fleharty, and P. B. Dunnigan The distributional status of bats in Kansas. Univ. Kansas Mus. Nat. Hist. Misc. Publ., 46:1-33. ():
1983 Jones, J. K., Jr., D. M. Armstrong, R. S. Hoffmann, and C. Jones University of Nebraska Press, Lincoln, NE. 1-379pp.
2000 Sparks, D. W., and J. R. Choate Distribution, natural history, conservation status, and biogeography of bats in Kansas Pages 173-228 in Reflections of a Naturalist: Papers Honoring Professor Eugene D. Fleharty Fort Hays State University, Hays, KS. pp.
2003 Cryan, P. M. Seasonal distribution of migratory tree bats (Lasiurus and Lasionycteris) in North America ():
2008 Timm, R. M., G. R. Pisani, J. R. Choate, N. A. Slade, G. A. Kaufman, and D. W. Kaufman http://www.ku.edu/~mammals, . pp.
Account Last Updated:
8/21/2018 7:54:31 PM


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