Evening Bat

Nycticeius humeralis

A female evening bat (Nycticeius humeralis) named ‘Io’ at the WildCare Foundation.

At-a-Glance

• Mating: Polygamous

• Peak Breeding Activity: fall

• Young are Born: May and June

• Feeding Periods: One hour or two after sunset and before sunrise.

• Typical Foods: Insects, especially beetles, flies and moths.

Description

This medium-sized brown bat looks like a smaller version of the big brown bat. The hair on its back is a bronze-brown, whereas the hair on its underside is slightly lighter. The muzzle is hairless and black.

Habitat and Habits

The evening bat can be found in mid- and southern Ohio, although it is rarely encountered. They roost in buildings and tree hollows in summer. It is not exactly known where they roost in the winter; they probably migrate south.

Reproduction and Care of the Young

Little is known about exactly when and where evening bats mate. In most Midwestern bats, mating takes place in the fall. Although sperm is transferred to the female during copulation, ovulation and fertilization of the egg are delayed until following spring. They usually have two pups in a litter. At four to six weeks, the pups are weaned and learn to fly.