American ermine hunts well above its weight class, killing rats and hares several times its own size before hauling the kill through tunnels barely wider than its skull. Pennsylvania’s 19 records come entirely from GBIF rather than iNaturalist, the kind of split you’d expect for a small, fast weasel that’s rarely caught on camera and more often turns up in trapping or specimen data.
Reports peak from May through July. That may reflect when ermines are easier to detect rather than a true population swell. With no NatureServe rank in this overlay for Pennsylvania, its state-level status isn’t formally assessed here. Pymatuning, Presque Isle, and Delaware Water Gap are useful places to start looking, but the records don’t establish that ermines are most abundant there.
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