Iowa’s occurrence data includes more records for this mouse than for any other small mammal covered in this set, 785 in all, evidence of how easily it turns up in survey traps set along the state’s countless farm edges and fencerows.
Built for Iowa’s fragmented, edge-heavy landscape
This mouse doesn’t need a big, unbroken block of forest the way some woodland species do. It uses exactly the scattered cover that row-crop farming has left across most of Iowa: hedgerows between fields, brushy fencerows, small farm woodlots, and the timbered stream corridors that survived because they sat too close to water or too steep to plow. Northeastern Iowa’s Mississippi River corridor, with its wooded bluffs and floodplain forest, adds a denser block of that same kind of cover.
The mouse behind a real Iowa health concern
Beyond its own natural history, this species carries outsized ecological weight as the main host that ticks pick up Lyme disease bacteria from before they ever bite anything else. Iowa has recorded a real rise in Lyme disease cases in recent years, concentrated in the state’s more wooded northeast, and this mouse’s role in that tick life cycle is a documented part of the reason.
Status in Iowa
NatureServe ranks the species S5, secure, in Iowa. It’s not listed as nonindigenous by USGS NAS, so it’s native to its Iowa range, and records here run year-round, with activity timing that the data shows varying by habitat across the state.
Full species profile
