Based on 1,490 research-grade iNaturalist observations in Connecticut, Eastern Chipmunk is most often recorded in May; in Connecticut it behaves like a summer visitor / breeder. It ranks #5 among mammals recorded in the state in our data.
Tamias striatus
Eastern Chipmunk in Connecticut by month
Bars show research-grade observations per month. They mix true seasonality with how often people are outdoors, so treat small numbers with caution.
Also seen in Connecticut in May

Eastern Cottontail

Eastern Gray Squirrel

White-tailed Deer

Groundhog
Red Fox

Common Raccoon

Bobcat
American Black Bear
Places to look in Connecticut
Connecticut College Arboretum
Marsh Botanical Garden
Gillette Castle State Park
Hammonasset Beach State Park
Bigelow Hollow State Park
Dinosaur State Park and Arboretum
FAQ
When does Eastern Chipmunk appear in Connecticut?
Mainly April–October, with the most records in May.
How common is Eastern Chipmunk in Connecticut?
It ranks #5 by number of iNaturalist observations among mammals in Connecticut (1,490 records in our sample).