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Little Brown Bat

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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