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Posts tagged “Eptesicus fuscus

Female Big Brown Bats Forming Maternity Roosts

5-7-15  big brown bat 022Big Brown Bats have emerged from hibernation and have been active for several weeks. It is in the spring that a female Big Brown Bat becomes fertilized with sperm she has stored in her uterus over the winter. Reproductive female Big Brown Bats collectively form a maternity roost at this time of year and each bat typically gives birth to a single pup in June, after about a 60-day gestation period.

While both Little and Big Brown Bats were affected by the fungus causing White Nose Syndrome, the Big Brown Bat population has not been decimated like the Little Brown Bat population. In some locations, Big Brown Bats have even thrived, taking over summer roosting spots formerly occupied by Little Brown Bats.

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Big Brown Bat

New England is home to both the Little Brown Bat and the Big Brown Bat. While the Big Brown Bat’s wingspan is a bit larger than the Little Brown Bat’s, the physical differences between the two species are quite subtle. If you can get a close look at the face of either one, you stand a good chance of being able to identify it by the shape of its nose and the presence or absence of fur on its face. The nose of the Little Brown Bat is short (and looks as if it has been squished) and it is almost entirely covered with fur, while the Big Brown Bat’s nose is relatively long and there is very little fur between its ear lobes and the tip of its nose.