Eptesicus fuscus
Big Brown Bats are one of
the most common bats in Northern Virginia, as well as the
largest. Their bodies are about five inches long, not
counting the tail, and they have a wingspan of up to 13
inches. Big Brown Bats have brown
fur above, and paler fur below. Their wings are black and
have no fur. They only weigh about half of an
ounce. Big Brown Bats can be
found all over. They live in forests,
cities, parks, and farms. Copyright, James F. Parnell Copyright, Bull Snook Big Brown Bats roost in
hollow trees, buildings, caves, storm sewers, and under
bridges. In Winter, they hibernate,
often in buildings and usually alone. Big Brown Bats breed from
November to March. After breeding
season, they form maternity colonies (mothers and babies) of
up to 600 bats. Female bats give birth to one or two young
(usually twins). Young bats can fly in three to four
weeks. Mothers communicate to
their babies with high-pitched squeaks. Males do not
participate in raising young. Big Brown Bats often live
over 10 years. Copyright, Patrick Coin, used with permission Big Brown Bats eat
insects, especially flying beetles. They also eat moths,
wasps, flies, stinkbugs, dragonflies, flying ants,
mosquitos, lacewings, planthoppers, and
leafhoppers. These bats catch their
prey
while flying. They do not see their prey. To hunt, they use
echolocation. This means they send out high-frequency sounds
(humans can't hear them) which bounce of objects, big and
small. Then they can listen to the echoes and tell where
things are, what size they are, and how they're
moving. Big Brown Bats catch
insects in their wings.
Copyright, J. Scott Altenbach