Blanding's turtles, Emydoidea blandingii (Emydidae), live in south-central Canada and north-central
United States. They are found in and around shallow weedy ponds, marshes, swamps, and lake inlets and coves most of the year.
This species, as many other long-lived vertebrates, is characterized by high adult survival rates and delayed sexual maturity. These two characteristics severely constrain the ability of turtle populations to cope with additive mortality associated with environmental disturbance such as predation, car accidents etc.
The females postpone maturity from 14 to 21 years of age. They are iteroparous, meaning that they are able to reproduce several times during their life cycle, from the age of 14 until the end of their lives. In practice, less than half of the adult females will reproduce in a given year. Reproduction occurs through internal fertilization with copulation taking place in the water. Females may travel considerable distances from the water to find suitable nest sites to lay their eggs. Each clutch constitutes an average of 10.2 eggs annually. The hatchlings should handle with predation since they have virtually no defenses to survive their attacks, and should also travel great distances back to aquatic habitats. During this period of time, they are cryptic and secretive, which may be their strategy to avoid predation. Since few young are ever encountered in the wild, it is presumed that the hatchlings are extremely unlikely to survive the initial weeks away from the nest.
Turtles also roam during at least some part of their annual life cycle, which includes daily wandering to exploit ephemeral food supplies and seasonal migration to lay eggs or escape drought or freezing temperatures. These movements expose them to many hazards, including roads.
However, the individuals that survive those risks enjoy high survivorship. The annual survivorship of adult females exceeds 93% and some individuals can live up to 110 years.