Hoary Bat: Lasiurus Cinereus

Photo of hoary bat wings

The Hoary Bat is the southeastern United States’ largest tree bat, ranging in total length from 13-15 cm. This tree bat species will roost in the forest and migrate based on weather patterns.

This bat is well known for its silvery-white frosted coat and its relentless appetite for insects. Typically living alone (unless mating), it’s not common to see groups of these bats.

Learn More: American Bats

Physical Characteristics

Lasiurus cinereus (Hoary Bat), with long narrow wings, is a large and distinctly marked bat. Its fur is long and soft, dark brown to black at the base, followed by a wide, cream-colored band, followed by a slightly narrower, white-tipped, mahogany brown band.

From the surface, the outer three colors are visible, giving a hoary appearance to the fur. Under its chin, the bat has a distinctive yellowish-brown neck and yellowish ears outlined in black.

Dense fur extends along the wings’ underside to the tip of its tail and just beyond the wrists.

The forearm measures 50-57 mm, and this bat weighs in at 20-38 g. This bat species is distinguishable by its unique colors and size. 1Go To Source tpwd.texas.gov -“Hoary Bat (Lasiurus cinereus)”

Hoary Bat Behavior

Hoary bats can fly as quickly as 13 miles per hour and as high as 8,000 feet, stopping at night to hunt for moths, mosquitoes, and occasionally other bats.

This bat species is not very social, preferring to lead mostly solitary lives tucked away in the tree foliage. Females move to the northern, eastern, and central United States after mating in autumn to give birth, often to twin pups (not common in bat species) in mid-May to early July. Males will remain in the western United States’ mountainous areas. 2Go To Source batcon.org -“SPECIES SPOTLIGHT: HOARY BAT”

Hoary Bat Reproduction Habits

In North America, hoary bats breed in Kansas, Kentucky, Arkansas, Louisiana, Georgia.

Around the time of the autumn migration, hoary bats are thought to mate. Before, during, or after the southward migration, researchers are uncertain when exactly mating occurs. Courtship is believed to happen during the day while the bats are flying.

Mating is followed by delayed fertilization, a method in which the sperm is stored throughout the winter in the female reproductive tract and does not fertilize the egg until the following spring. Little is known about the duration of pregnancy in these bats.

From the middle of May to early July, births tend to occur. The size of a litter is typically 2-4 baby bats.3Go To Source biokids.umich.edu -“Hoary bat Lasiurus cinereus”

Habitat Of The Hoary Bat

Photo of hoary bat white fur

Hoary bats roost alone, and maternity colonies rarely, if ever, form. In both hardwood and coniferous forests, they roost readily and prefer large, mature trees. For warmth, they roost 10-15 feet above the ground on branches between leaves oriented southward. They can often be mistaken for pinecones at first glance due to their coloring, but Hoary bats are bigger and less maneuverable than other bats and tend to forage at high altitudes or in open areas. 4Go To Source dnr.wi.gov -“Hoary Bat”

Hoary Bat Range

The hoary bat, ranging from northern Canada to Guatemala, is widespread and is likely to occur in all states except Alaska—even in Hawaii, where it is the only native land mammal.

Hoary Bat Diet

Like most bats, the hoary species feeds upon insects. Their favorite meal seems to be large moths and beetles.

There have been recordings of hoary bats attacking eastern pipistrelles (smaller species of bat), but the hoary bat will typically stick to an insectivore diet. 5Go To Source esf.edu -“Hoary Bat (Lasiurus cinereus P. de Beauvois)”

Insects Eaten By The Hoary Bat Species

  • Grasshoppers
  • Mosquitoes
  • Beetles
  • Wasps
  • Dragonflies
  • Moths

Hoary Bat Conservation

Hoary bats and other migratory species are receiving massive hits along their migration routes from wind farms. Recent research estimates that about 500,000 bats (mainly red bats, hoary bats, and silver-haired bats) have been killed in the U.S. by wind turbines every year.

Researchers believe that bats are drawn to the turbines because they see them as a roosting location. Bats are either hit by fast-moving blades or killed by barotrauma.

To tackle this emerging issue, a working group called the Bats and Wind Energy Cooperative (BWEC) was formed in 2003. Solutions include seasonal adjustments to the cut-in speeds of turbines, acoustic/light deterrents, and avoiding the development of turbines in high-risk locations. 6Go To Source conservewildlifenj.org -“New Jersey Endangered and Threatened Species Field Guide”

 

 

Sources:

  1. “Hoary Bat (Lasiurus Cinereus).” Texas Parks & Wildlife, tpwd.texas.gov/huntwild/wild/species/hoary. Accessed 10 Dec. 2020.
  2. Nunn, John. “Species Spotlight: Hoary Bat.” Bat Conservation International, 23 Feb. 2017, www.batcon.org/species-spotlight-hoary-bat/#:%7E:text=Hoary%20bats%20may%20fly%20as,mosquitoes%20and%20occasionally%20other%20bats.&text=These%20solitary%20bats%20seldom%20enter,concealed%20in%20the%20tree%20foliage.
  3. Wisconsin DNR. “Hoary Bat (Lasiurus Cinereus).” Wisconsin Department of Natural Resources, 8 Oct. 2020, dnr.wi.gov/topic/EndangeredResources/Animals.asp?mode=detail&SpecCode=AMACC05030.
  4. Anderson, S. 2002. “Lasiurus cinereus” (On-line), Animal Diversity Web. Accessed December 10, 2020 at http://www.biokids.umich.edu/accounts/Lasiurus_cinereus/
  5. Saunders, D. A. “Hoary Bat | Adirondack Ecological Center | SUNY ESF | College of Environmental Science and Forestry.” SUNY College of Environmental Science and Forestry, 1988, www.esf.edu/aec/adks/mammals/hoary_bat.htm#:%7E:text=They%20frequently%20eat%20large%20moths,upon%20smaller%20species%20of%20bats.
  6. Kopsco, Heather, and MacKenzie Hall. “Wildlife Field Guide for New Jersey’s Endangered and Threatened Species – Conserve Wildlife Foundation of New Jersey.” Conserve Wildlife Foundation Of New Jersey, 2014, www.conservewildlifenj.org/species/fieldguide/view/Lasiurus%20cinereus.