The dwarf shrew is one of the tiniest mammals in North America, light enough to be mistaken for an insect skittering through leaf litter, and Montana’s record reflects how rarely anyone documents it. Twenty-nine records since 2000, and 16 of those come from a single place: Carter County, in the state’s far southeast corner.
That lopsided count almost certainly tracks survey effort rather than the shrew itself. One well-worked study area can outproduce the rest of a state put together, and dwarf shrews usually turn up in pitfall traps set for other work. The remaining records scatter across seven more counties, from Golden Valley and Fergus north toward the Hi-Line, with a July and September crest that matches the summer field season.
The scarcity cuts both ways. NatureServe ranks the dwarf shrew Imperiled (S2) in Montana even though it’s Apparently Secure globally, because the state holds a thin northern edge of its range. For an animal this easily overlooked, every record genuinely shifts the picture of where it lives in the state.
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