House mouse records follow California’s human landscape: ports, farms, suburbs, warehouses, and city parks. Coastal population centers and the Central Valley’s agricultural belt are therefore better represented than remote mountains and deserts.
August contains an extreme spike in the monthly series, unlike the much lower totals in every other month. That shape is more consistent with a concentrated survey or imported batch of records than a sudden statewide increase. Most reports also come from museum and survey sources, so the curve can’t measure California’s mouse population.
Full species profile
