RodentHow to Identify ItWhere It Enters in SpringfieldPeak Season
House MouseSmall (3 in. body), grey-brown, pointed snout, tiny rice-grain droppingsPencil-width gaps at utility lines, garage thresholds, weep ventsYear-round; spikes Oct–Feb
Roof RatSlender, dark, long tail longer than body, agile climberRoofline, soffit, and gable gaps reached via tree canopyFall through winter
Norway RatLarge (heavy body), brown, blunt nose, tail shorter than bodyGround-level burrows, slab cracks, sewer and drain linesYear-round; rises after wet springs