Bats are small, winged mammals, with wingspans of 25 to 63 cm, depending on the species. The head and body are covered with fur, and the membraned wings connect the hind legs, body, and forelimbs. Another membrane connects the small hind legs to the tail.
These nocturnal animals feed on insects, primarily those active at night.
Bats are common in the Northwest. In spring, females roost in buildings, bridges, caves, and tree cavities to birth and rear young. Adults leave roosts at night to forage for insects. In late summer or fall, males join the colony for breeding, after which the bats sometimes might migrate to warmer areas or hibernation roosts.
Bats prefer to roost on dark, hard surfaces, such as cement duct work and chimneys. They can cause problems with noise, structural damage, and loss of ventilation; in addition, droppings and urine can accumulate, creating odors and attracting insects; and they can transmit diseases, such as rabies.