[1] The mating season for the Townsend's big-eared bat takes place in late fall.

As with many other bat species, the female stores sperm in her reproductive tract after mating, and fertilization occurs in the spring.

[4] One study found the average lifespan of a Townsend's big-eared bat to be 16 years.

[2] During summer, these bats inhabit rocky crevices, caves, and derelict buildings.

Townsend's roost singly during hibernation, forming small clusters only rarely.

Before hibernation, C. townsendii individuals increase their body mass to compensate for the food they do not eat during the winter.