Turtles are reptiles that have a bony or cartilaginous shell developed from their ribs that acts as a shield. Turtles are found on every continent except Antarctica and live in freshwater, terrestrial, and marine environments. There are around 356 species of turtles and tortoises worldwide. Here we will discuss the 7 most common turtle species.
Turtles belong to the order Testudines which includes all living turtles, tortoises, and terrapins. They are some of the oldest reptiles on Earth, with fossils dating back over 200 million years. Turtles vary greatly in size, shape, and habitat. The largest turtle is the leatherback sea turtle which can reach up to 6 feet (1.8 m) long and weigh over 2,000 pounds (907 kg). The smallest turtle is the speckled Cape tortoise which only grows up to 3.1 inches (8 cm) long.
Turtles are ectothermic, meaning they rely on external sources to regulate their body temperature. They also have a slow metabolism and can live to very old ages. The oldest known turtle lived to be 188 years old! Turtles lay eggs on land, though some species retain the eggs inside the body until they are ready to hatch. Hatchlings are born fully formed and ready to take care of themselves.
There are 14 turtle families which are further divided into subfamilies and genera. The 7 most common turtle species come from 5 different families:
Red-Eared Slider
Scientific Name: Trachemys scripta elegans
Family: Emydidae
Red-eared sliders are a semiaquatic turtle native to the central and southern United States. They get their name from the distinctive red patches around their ears. These turtles are popular pets around the world due to their small size, hardy nature, and longevity.
Red-eared sliders have green bodies with yellow striping on their heads, legs, and tails. Their upper shell is dark green and their lower shell is yellow with dark, circular markings. Males are smaller than females, growing to 5-7 inches compared to females that are 8-12 inches long.
Habitat
Red-eared sliders live in slow-moving fresh bodies of water like ponds, lakes, creeks, and marshes. They prefer areas with soft mud banks or rocks to bask on. Though sliders spend most of their time in the water, they leave the water daily to bask in the sun. This allows them to regulate their body temperature.
These turtles live across a wide geographic range including the eastern half of the United States and parts of northeastern Mexico. They thrive in warm climates and cannot survive cold northern winters. When the weather cools, they burrow into the mud at the bottom of the water and become dormant until spring.
Diet
Red-eared sliders are omnivores, feeding on both plant and animal matter. Aquatic plants make up half their diet. They also eat insects, small fish, tadpoles, snails, worms, shrimp, crayfish and other small invertebrates. Hatchlings start out as carnivores, eating mostly insects and moving onto more vegetation as they mature.
Painted Turtle
Scientific Name: Chrysemys picta
Family: Emydidae
Painted turtles are aptly named for their beautifully colored shell markings. They are small to medium-sized turtles common across North America. There are four subspecies of painted turtle: eastern, midland, southern, and western.
These turtles have olive to black upper shells with red, orange, or yellow stripe markings. Their skin is olive green and legs are marked with red streaks. Painted turtles have webbed feet for swimming. Like many turtles, males are smaller (3-5 inches long) than females (5-8 inches long).
Habitat
Painted turtles inhabit shallow freshwater ponds, marshes, creeks, and lakes across much of North America. They prefer calm, slow-moving water bodies with soft, muddy bottoms and abundant aquatic vegetation. These turtles require basking areas like logs or rocks to regulate their temperature.
Painted turtles range from southern Canada through the United States and down into northern Mexico. The four subspecies each have a distinct geographic range. Eastern painted turtles are found from southeast Canada to Georgia. Midland painted turtles occupy the Great Lakes region. Southern painted turtles live from Kansas to Alabama. Western painted turtles span central Canada through the Pacific Northwest and Southwest.
Diet
Painted turtles are omnivores, feeding on both plant and animal matter. Aquatic plants like duckweed, algae, and lily pads make up a large portion of their diet. Small fish, insects, worms, tadpoles, and crustaceans round out their food sources. Hatchlings eat more protein-rich animals before expanding their diet to more vegetation.
Snapping Turtle
Scientific Name: Chelydra serpentina
Family: Chelydridae
The common snapping turtle is the largest freshwater turtle in North America. They are well adapted to their aquatic habitat with a smooth, streamlined shell and thick, webbed feet for swimming. These turtles get their name from their long neck and powerful beak-like jaws.
Snapping turtles have dark brown or black upper shells. Their undersides are lighter brown or olive. Their skin is dark with some algae growth. Older turtles may have rough, jagged shells. Snapping turtles are very large, with a shell up to 19 inches long. Males are smaller than females.
Habitat
Snapping turtles live in slow-moving fresh and brackish water habitats across eastern North America. They are found as far south as Florida and north into Canada. These turtles prefer muddy areas like swamps, marshes, ponds, or streams. Snappers may wander over land but always live near permanent water sources.
In cold winter months, snapping turtles burrow into the mud at the bottom of their water habitat and hibernate until warmer spring temperatures return. Their wide geographic range means they experience a variety of temperate, subtropical, and tropical climates.
Diet
Snapping turtles are primarily carnivorous, feeding on fish, frogs, snakes, small birds and mammals, leeches, crayfish, worms, insects, and other turtle’s eggs and hatchlings. They ambush prey by lying still in the water with jaws open before snapping their strong neck and jaws to capture food. They will also scavenge dead organisms.
Box Turtle
Scientific Name: Terrapene genus
Family: Emydidae
Box turtles get their common name from their domed, boxy upper shell. They are one of the most recognizable turtle species due to their hinged lower shell that allows them to completely seal themselves inside their shell.
There are six subspecies of box turtle in North America: Eastern, Florida, Gulf Coast, Mexican, Ornate, and Spotted. They range from 4-7 inches long and have ornate shell markings that vary by subspecies. Box turtles live entirely on land.
Habitat
Box turtles inhabit wooded and grassy areas across the eastern and central United States. They have a more terrestrial lifestyle than many turtles but require loose, moist soil to bury themselves during extreme weather and winter hibernation.
Different subspecies have distinct geographic ranges. Eastern box turtles span from Maine to Florida. Ornate box turtles occupy the midwestern plains. Spotted box turtles live along the Gulf Coast while Florida box turtles only inhabit Florida.
Diet
Box turtles are omnivores that feed on a wide variety of vegetation and animals. They eat slugs, snails, worms, insects, berries, mushrooms, flowers, fruits, and eggs. Box turtles locate food through a strong sense of smell and excellent vision. They use their beak to crush their prey before swallowing it whole.
Green Sea Turtle
Scientific Name: Chelonia mydas
Family: Cheloniidae
The green sea turtle is a large marine reptile that inhabits tropical and subtropical coastal waters worldwide. They are named for the green color of their cartilage and fat rather than their outer shell and skin which vary in shade from black to grey, blue, or brown.
Green sea turtles have a smooth, heart-shaped shell called a carapace which can reach over 3 feet long in adults. Their forelimbs have evolved into flippers to propel them easily through the ocean. These turtles are entirely herbivorous, feeding on seagrasses and algae.
Habitat
Green sea turtles live in shallow, coastal waters in tropical regions where their food sources grow abundantly. They are found near reefs, bays, lagoons, and inlets from Mexico along the Atlantic coasts of Central and South America across to Africa, South Asia, and into the Pacific.
Green sea turtles undertake long migrations from feeding grounds where mature adults live to nesting sites visited every 2-4 years for breeding. Females return to the exact beach where they first hatched to lay eggs. Males do not leave the ocean habitat.
Diet
Green sea turtles are herbivorous grazers, feeding almost solely on seagrasses and algae. Their jaws are finely serrated, adapted to marine vegetation. Hatchlings eat more plankton before transitioning to the vegetarian diet. Green sea turtles can consume over 2 pounds of grasses and algae per day.
Loggerhead Sea Turtle
Scientific Name: Caretta caretta
Family: Cheloniidae
Loggerhead sea turtles are the most abundant sea turtle species in United States coastal waters. They get their name from their large, blocky head. Loggerheads have a reddish-brown shell and light yellow underside. Adults can weigh up to 500 pounds.
Loggerheads are long-distance ocean travelers, undertaking lengthy migrations between feeding and breeding areas. These turtles have a slow growth rate and late sexual maturity, not breeding until 25-30 years old. Loggerheads face threats from human activities like fishing, pollution, and habitat destruction.
Habitat
Loggerheads occupy marine ecosystems worldwide from the tropics to temperate coastal areas. In the United States, loggerheads nest along the Atlantic coast from Florida to as far north as Virginia as well as the Gulf Coast. After hatching, young loggerheads swim out to sea, inhabiting floating mats of sea plants.
As juveniles, loggerheads live in the open ocean before migrating back to nearshore coastal waters as adults. Here they inhabit coastal bays, estuaries, lagoons, and mouths of large rivers for feeding. Loggerheads have the widest geographic range of any sea turtle.
Diet
Loggerhead sea turtles have powerful jaws adapted for crushing and eating hard-shelled prey like whelks, conch, and crabs. They also eat fish, jellyfish, squid, shrimp, sea urchins, sponges, and mollusks. The young feed on floating seaweed and animals. Adult females gain 300 pounds in preparation for breeding.
Leatherback Sea Turtle
Scientific Name: Dermochelys coriacea
Family: Dermochelyidae
The leatherback is the largest sea turtle and one of the most migratory, able to cross entire oceans. They are named for their leathery, rubbery carapace which lacks the hard scutes or bony plates found in other sea turtles. Their dark grey or black carapace helps camouflage them in the deep ocean.
Leatherbacks lack scales and have a uniquely ridged, tapered shell. Their front flippers are proportionally longer than other sea turtles to power their lengthy migrations. Mature leatherbacks average 4-6 feet long and weigh 500-2,000 pounds. They are known to dive deeper than 3,000 feet.
Habitat
Leatherbacks have the widest distribution of any reptile, inhabiting tropical to subpolar seas worldwide. They migrate extensively between nesting beaches and foraging areas. Leatherbacks can tolerate cold water better than other turtles allowing them to range into Canada and Norway.
Females nest on sandy tropical beaches before migrating thousands of miles into temperate waters abundant with jellyfish prey. Males never leave their pelagic ocean environment. After hatching, young leatherbacks swim out to sea where they live for several years before returning to nesting sites.
Diet
Unlike other sea turtles, leatherbacks are almost exclusively jellyvores, meaning they feed heavily on jellyfish and similar soft-bodied invertebrates like salps, squid, and sea urchins. Their sharp, scissor-like jaws easily slice through and ingest this slippery prey. Leatherbacks help control jellyfish populations.
Conclusion
Turtles are amazing reptiles that come in all shapes, sizes, and lifestyles. The 7 species highlighted here display the great diversity found across the 356 turtle species on Earth. From tiny speckled Cape tortoises to giant leatherback sea turtles, these reptiles have evolved for over 200 million years to fill aquatic, terrestrial, and marine niches worldwide.
Though many populations still face habitat loss and other human-caused threats, greater awareness and conservation efforts focused on turtles gives hope for the continued survival of these ancient, unique animals. Scientists believe over 60% of turtles species are currently threatened or endangered, so more work is needed to ensure future generations can still enjoy their presence.
