Few Maryland mammals are recorded as often as the eastern chipmunk. More than 1,300 reports make it one of the most-recorded mammals in the state, and the map runs from the coastal plain clear to Garrett County’s mountains. Read the county leaders carefully, though. Montgomery, Frederick, and Baltimore counties top the list, and those are also where the most people live, hike, and file reports. Records trace observers as much as chipmunks.
The seasonal rhythm is the real signal. Reports surge through May and June, when chipmunks are out in force and newly independent young start showing, then taper through fall before collapsing to near nothing from November through February. Chipmunks don’t truly hibernate, but they spend much of the winter underground, waking now and then to raid their stored caches, and the record shows it.
The named places read like a tour of the state’s wooded parks: Catoctin Mountain, the Appalachian Trail corridor, the C and O Canal, Deep Creek Lake. Wherever mature woods meet stone walls and leaf litter, chipmunks do well, which is why NatureServe ranks them Secure (S5) in Maryland. This is one of the rare cases where heavy records and real-world abundance line up.
