During the summer months, individuals may disperse into nearby woods and fields in search of prey. Although normally active during the daylight hours, massasaugas may resort to evening and nighttime activity to escape the mid-summer heat. The massasauga feeds primarily on small rodents, but may also take a variety of small animals including other snake species, shrews, and an occasional frog or nesting bird. Massasauga rattlesnakes range from central New York and southern Ontario west to the prairies of Iowa and Missouri. The eastern massasauga is strongly associated with wetlands across most of its range.
Wet prairie is the preferred habitat in the west, bogs and swamps in the east.
The northern populations in Ontario, Canada, around Georgian Bay are found in rock outcrop areas that are more similar to the habitat where we find timber rattlesnakes. Massasaugas frequent other wet, lowland habitats, including marshes and floodplains. Locations that provide open sunny areas with elevated hummocks for basking as well as shaded areas for retreat are ideal. The hummocks are also used as a place for bearing young and, most importantly, for hibernation during winter months. In the summer, the massasauga often moves to drier, upland areas.