By Stacey Venzel
Turtles have been found everywhere except Antarctica. Their survival for 245 million years suggests they are incredibly adaptable creatures when it comes to their environment.
Members of the Testudines family can be found on land and in water. Some species live in distinct hidden habitats, making use of their surrounding landscape to aid in protection. Habitat might also change for an individual if it migrates to a specific feeding zone.
Tortoises live on land, and some aquatic turtles traverse rocky, volcanic, forested and sandy terrain as well. Species such as the Galapagos tortoise are restricted to regions like the Galapagos Islands. Hinge-back tortoises dwell in dry and wet regions of Africa with extensive vegetation. The African spurred tortoise, more commonly referred to in the pet trade as the sulcata tortoise, bears the desert heat in self-dug burrows. Tortoises are native to all continents withstanding Australia.
Freshwater and semiaquatic species can be found anywhere from lakes and rivers to ponds, bogs, swamps, wetlands and estuaries. The diamondback terrapin inhabits brackish waters along the eastern United States and as far south as Bermuda. The flippered Fly River turtle, more commonly known as the pig-nosed turtle, is restricted to rainforest streams in New Guinea and the northern tip of Australia. The common snapping turtle is found in freshwater parts of North America, Central America and even Ecuador. The big-headed turtle employs low-lying branches for hiding or digs its own burrows around Asia.
Sea turtles are the only turtles that live strictly in saltwater. Many, like the hawksbill, call coral reefs home, tucking their head into crevices for protection. Green sea turtles are often spotted foraging in sea grass beds. The Flatback sea turtle has only been discovered in Australian and New Guinean waters. Kemp’s Ridleys spend most of their lives in the Gulf of Mexico with almost all of their nesting occurring on the same beach in Rancho Nuevo, Mexico.
Where a turtle is found in the water column can vary within a species depending on feeding and the time of the year. However, turtles can only dive to a certain depth before the pressure on their bodies is too much and they build up potentially toxic levels of carbon dioxide in their bloodstream. Though the adaptations vary among species, sea turtles are generally considered the best divers. Many turtles stay warm by basking in shallow waters while others burrow in deeper depths during the winter. The common snapping turtle looks for prey on the bottoms of lakes as well as on the banks. Though some turtles routinely dive thousands of feet down to feed, such as the leatherback sea turtle, most sea turtles stay in the top 650 feet of the water column, known as the epipelagic zone.
The leatherback sea turtle has the widest range of any turtle. It is found in all five oceans, meaning they can handle tropical seas and arctic zones. In addition to coming ashore to lay eggs and spending time at the surface in all life stages, adults can dive down to a depth of 3,000 feet. Individuals migrate about 10,000 miles a year!