| Latin Name
| Conservation Status
||Western North America
||90 - 113 mm (3.5 - 4.4 inches)
||40 - 50 mm (1.6 - 2 inches)
||Approx. 280 mm (11 inches)
||5 - 14 g (0.2 - 0.5 oz)
| Life Expectancy
||Up to 10 Yrs
Townsend's Big-Eared Bats are medium sized bats. Their length is between 90 and 113 mm (3.5 - 4.4 inches, their tail length is between 40 and 50 mm (1.6 - 2 inches), their wingspan is approximately 280 mm (11 inches) and they weigh between 5 and 14 g (0.2 - 0.5 inches).
Their upper side is coloured brown and their underside is slightly paler. Between their hind legs the membrane is full, wide and hairless. They have extremely large ears that measure between 30 and 39 mm (1.2 - 1.5 inches) and on each side of their snout they have a small glandular outgrowth.
Townsend's Big-Eared Bats are found in western North America. They inhabit mines, caves and old buildings during the summer but during the winter months they hibernate in tight clusters.
During the summer months males and females inhabit separate colonies. Males tend to be solitary while females and their young gather in large maternity colonies that contain 20 - 200 individuals.
Townsend's Big-Eared Bat feeds on various nocturnal flying insects, but mainly small moths. Their diet also includes lacewings, true flies, beetles and wasps. They often catch their prey in the air near the foliage of trees and shrubs.
After a gestation period of 50 - 60 days, 1 young bat is born in mid June. When they are born they are blind and hairless. By the time they are 3 days old they are covered in light grey fur and after 1 week their eyes are open and their ears are erect.
They are able to fly by the time they are 3 weeks old and they are weaned when they reach 6 - 8 weeks old.
Young males do not breed in their first year, but females are capable of breeding at any time.
The main predators of Townsend's Big-Eared Bats are likely to be raccoons, snakes, hawks and owls.
Townsend's Big-Eared Bats are also known as:
Mexican Big-Eared Bat
Rafinesque's Big-Eared Bat