Peak Nuisance Period: Third week of July through the First week of August.Common Nuisance Situations:
- Females may roost in colonies in buildings to raise their young. Their guano and urine can damage insulation and household goods and attract other pests.
- Sometimes, a lone bat enters the house and flies around. This usually happens in July and August, when the young are learning to fly.
- During an extreme heat wave, several bats may enter the living quarters, seeking a cooler roost. This is when they’ll show up in places they normally don’t use.
- Big brown bats will hibernate in buildings (little browns don’t seem to.) In the winter, a big brown bat may leave its roost in the attic and fly around in the living spaces. This usually happens when the temperature of the attic roost changes dramatically, disturbing their hibernation—during a thaw, or during the very coldest part of the winter, if the attic is much colder than the rest of the house.
- Disease risks: Rabies, histoplasmosis. In New York, bats are a rabies vector species.
Description: There are two types of bats that are commonly known to roost in buildings in New York and New Jersey, the Little Brown Bat and the Big Brown Bat. Little Brown Bats are approximately 3 to 4 inches long and have a 9 inch wing span. These are the most abundant species of bat found in New York and New Jersey. Big Brown Bats are 4 to 5 inches long and have a 12 inch wing span. They have a brownish nose, long hairs on their toes—hair sticks out beyond the end of their toes, and the Calcor (the bone that juts back from the ankle bone) has no or a weak keel. Bats are nocturnal, with peek feeding times at dusk and dawn. During the winter they hibernate; both species migrate locally.
Diet: Entirely insects.
Habitat: Forests and forest edges, areas with lakes and ponds, parks, orchards, fields, suburbs, cities.
Breeding: Bats mate during the fall, but the females store the sperm in their bodies for months, fertilization does not take place until late winter or early spring. Gestation period id 50 to 60 days. Little Brown Bats have 1 pup; Big Brown Bats have 2 pups.
- All bats have rabies. WRONG. The Department of Health has been tracking Bat populations since 1965 and the number of rabid bats has remained constant at 3% to 4% of the over-all population.
- Bats almost never attack people.
- Bats do not go in your hair. They are excellent fliers and if you stand still they will not hurt you.
- Not all grounded bats are sick. Young pups can become grounded when they are learning to fly.
- The Bats that live in New York and New Jersey eat insects they don’t drink blood.