The range extends from southern Ontario and adjacent Quebec west to southeastern Minnesota and south to northwestern Pennsylvania, central Illinois and north-central Nebraska.There are a number of disjunct (cut off) populations east of Illinois. The most disjunct population is the one in Nova Scotia.
This population probably colonized Nova Scotia during a warm period after the last glaciation, about 5,000 years ago. Then about 3,000 years ago, the land bridge connecting Nova Scotia to New Brunswick was flooded and became salt marsh, preventing further colonization. Then the climate cooled, restricting the Blanding's Turtles to a small area in south central Nova Scotia where mean annual temperature is higher than in any other region in the Maritimes.
Nova Scotia Blanding's turtles hibernate underwater; elsewhere, these turtles are known to also hibernate in leaf litter at the edge of water habitats.
Nests are dug by females in sand and gravel beaches or gravelly soil, usually during late afternoon and evening from early June to early July.
Females produce from 10 to 12 eggs each year. Hatchlings emerge during September and October.
Raccoons are a major predator on the eggs. They find and dig up nests. Raccoon populations have been increasing in Kejimkujik, and so was predation. Since 1987, known turtle nest sites have been caged to try to protect the eggs.
Blanding's turtles are believed to live to be more than 75 years old, and to start reproducing at 15 years old.