Listen forMammals
Big brown bats hunting over yards at dusk in eastern Massachusetts
When: May to September
Big brown bats, the most common bat in Massachusetts suburbs, leave their roosts in the evening to hunt insects over yards, ponds and field edges.
Why this time of year
Young big brown bats usually leave their nursery colonies in late July and August, so an August evening sky over eastern Massachusetts can hold newly flying juveniles alongside the adults.
How to notice it
- Pick a warm, calm evening and face the open sky above a pond, field edge or streetlight just after sunset.
- Watch for fluttery, quick-turning flight; follow one bat with your eyes as long as you can.
- Stay clear of roosts and never touch a bat.
Try this with kids: How is a bat's flight different from a bird's?
white-nose syndrome: a fungal disease of cave-hibernating bats
Safety
- Never touch a bat, indoors or out.
- If a bat is found in a room where someone was sleeping, alert your local health officials.
- Do not approach or disturb roosts.
Sources
- mass.govBig brown bats are the most common and widespread bat in Massachusetts and the most common bat in suburban neighborhoods; they are insectivores that leave the roost in the evening to hunt; young are born May-June and usually leave the nursery colony in late July and August; the species is a habitat generalist and was the least affected by white-nose syndrome.
- mass.govNine bat species live in Massachusetts; after white-nose syndrome arrived, all four cave-wintering species were listed as Endangered in 2012, and the little brown bat declined by more than 99 percent, which is why the bat a family sees now is most likely a big brown bat.
- massaudubon.orgAll Massachusetts bats are insectivores hunting in a wide variety of habitats; nursery colonies break up in late summer; migration occurs in autumn; do not hit or throw things at a bat, and alert health officials if a bat is found with a sleeping person.
In the guide for May, June, July, August, September