What Pests Are Actually Active in June in New Hampshire?

Seven species hit peak simultaneously in June — ants, bats, cockroaches, opossum, raccoons, squirrels and ticks — second only to October's ten. That gap between June and October is worth sitting with: it's the clearest evidence on this whole calendar that the pest year has an actual shape, rather than the flat, same-seven-species-every-month picture the old calendar drew. June honestly is busy. March honestly isn't. The old calendar treated them identically, which was the whole problem.

Most of what's driving the count is simple warmth: full summer foraging for ants, accelerated breeding for cockroaches, and a second wave of activity for squirrels distinct from their winter peak.

The single most important fact in this month's changelog isn't a species turning up, it's a legal window closing. June sits in the middle of little brown bat maternity season, and New Hampshire's exclusion moratorium — running roughly mid-May to mid-August — exists specifically because flightless pups are present in a den during these months. Excluding adult bats now would trap pups inside, which is both illegal and needlessly inhumane.

If bats are already in a structure, June is a month to document and wait, not to act. The legal exclusion window reopens in late summer, once pups can fly.

Raccoons and squirrels both peak this month, for different reasons that land in the same place: an attic. Raccoon kits from April's birthing peak are now old enough to be genuinely destructive — this is when displaced insulation, chewed wiring and soiled areas typically get noticed. Squirrels, meanwhile, are having their second litters of the year, a distinct summer breeding peak separate from the winter one, which means a fresh wave of attic nesting activity even in a structure that seemed to have settled down in April.

Only birds turned down this month, as April and May's peak nesting intensity settles with early broods fledging — still active, just past its highest point. Everything else holding steady is the floor: fleas, mice, moths, rats and ticks, all present in June for the same reason they were present in January. Ticks deserve one honest caveat — June is the state's highest Lyme-transmission month, but that risk is a continuation of May's peak, not a new spike, which is exactly what the floor band is built to say plainly.