Blanding's turtle (Photo by Ryan M. Bolton)
Turtles of Ontario
Turtles, along with snakes and lizards, are reptiles. Turtles live in a wide variety of habitats, from the open sea's salt water to freshwater wetlands, from deserts to rainforests. As such, they also have varied diets, from completely carnivorous — consuming jellyfish, mollusks, fish and even shorebirds — to completely herbivorous — consuming cacti, algae and other vegetation.
Turtles are long-lived and reach sexual maturity late but can mate many times over a lifetime. All turtles lay eggs in nests of sand, gravel or vegetation. Eggs are buried after laying and a special tooth called an egg tooth helps hatchlings break out of their shell when they are ready. This egg tooth falls off a few days after hatching. Hatchlings often occupy a very different ecological niche than adults of their species, eating different foods and living in a different habitat. Most species of turtles have a temperature-dependent sex determination. The temperature during incubation determines whether a turtle will be male or female.
Turtles are ectotherms, meaning their body temperature is regulated by external influences like the hot sun or cold water. Human beings are endotherms and we regulate our temperature internally. You will often see turtles basking on rocks or logs on sunny days to absorb some radiant heat.
In Ontario there are nine turtle species. Because of the climate, all of Ontario’s turtle species hibernate underwater in ponds, rivers, wetlands or other freshwater sources, emerging in early April. Ontario's turtles can be grouped by size into three categories: small, medium and large.
Turtles are threatened by multiple issues and activities, including nest predation by animals such as raccoons, nest disturbance from human activities and ATV (all-terrain vehicle) activity at nest sites. Climate change may also have long term effects on the temperature-dependent sex determination mechanism.
For more information on Ontario's turtles, visit:
Ontario's Reptile and Amphibian Atlas (download the citizen science iPhone app)
Canadian Amphibian and Reptile Conservation Network
Toronto Zoo's Adopt-A-Pond