06/17/2026
Don't seal the attic this month.
If you've been meaning to seal up the gap where a bat slips into your attic, your soffit, or behind a shutter, please put it off. June and July are the one stretch of the year when sealing that gap doesn't evict a bat — it kills a family.
This is bat maternity season. Female bats gather in warm, hidden roosts to give birth and raise their pups, and a few of those roosts are in our buildings. Right now, behind that gap, there are very likely tiny pups that cannot fly. A bat is born helpless and stays grounded for roughly three to four weeks while its wings and muscles develop, clinging to the roost while its mother hunts all night and returns to nurse.
If you seal the entrance now, the adults are shut out and the flightless pups are sealed in. They don't move on — they can't. They starve in the walls, and what follows is the smell, the mess, and the heartbreak of having caused it without meaning to. It's one of the most common, avoidable wildlife tragedies of summer. In many places, it's against the law to do an exclusion during maternity season for exactly this reason.
So the rule for June and July is simple: leave the gap alone. The bats are temporary tenants, and they're paying enormous rent — a single little brown bat can eat its body weight in insects in a night, mosquitoes very much included.
When the pups can fly, usually by late summer, the colony naturally moves on — and that, in the fall after they've gone, is the time to seal the gap and keep them out for next year. Do it then, with a one-way excluder that lets bats leave but not return, and everyone wins: the bats live, and your attic is closed for next season.
A few more weeks of patience is all it takes. Seal it in the fall, never in June.