Tourists love seeing sea turtles on their ocean vacations. These gentle creatures swim majestically through the open ocean and provide many learning experiences for field trippers.
The number of varieties of sea turtles is huge, but we’ll discuss seven types of sea turtles found in the oceans.
Learn the sea turtle’s common name along with its scientific name. Habitat, average lifespan, and behavioral patterns will be discussed for each type. Most sea turtles are similar, but differences between each species make for fun facts. Be prepared to learn about some of the most loved sea creatures.
Table of Contents
What Is a Sea Turtle?
A sea turtle is a marine reptile. Unlike land and freshwater turtles, they cannot retract their heads and thick legs into their shells. Their extremities are fixed outside of the shell. Sea turtles have flippers instead of legs and feet like freshwater turtles have. These flippers allow them to swim effortlessly through the ocean.
Sea turtles come ashore annually to the sandy beaches to lay eggs. Their flippers make this journey more difficult, but it is short-lived. They bury their eggs under the sand on the nesting beaches and return to the ocean water.
When the eggs hatch, the sea turtle hatchlings dash for the ocean from the sea turtle nest. Many are eaten by birds and other predators on the nesting beaches and never make it. The hatchlings that do make it are in for a long life of inhabiting the ocean.
Sea turtles have long lifespans similar to humans. They can live to be over 50 years old, with females laying 1,900 to 2,300 eggs in their lifetime.
Most of these animals have hard shells (called Cheloniidae), but leatherback sea turtles have rubbery shells.
They are reptiles, which means they must breathe air. When they are active, a sea turtle must surface to breathe fresh air every few minutes. If they are resting, they can remain underwater for 2 hours without breathing.
The 7 Species of Sea Turtles
Below are seven of the most common types of sea turtles found around the world.
Leatherback Sea Turtle
Scientific Name: Dermochelys coriacea
Other Names: Leathery turtle, lute turtle, luth
Size: 550-1,500 lbs; 6-7.2 ft
Distribution: Endangered in the marine waters of the Atlantic, Pacific, and Indian Oceans.
The leatherback sea turtle is the only one that is not a Cheloniidae. Cheloniidae sea turtles have hard shells. Cheloniidae shells consist of a bony carapace on top and a plastron on the bottom with epidermal scutes covering. Instead of a hard shell like a Cheloniidae sea turtle or a freshwater turtle, leatherback turtles have rubbery shells. Leatherbacks are the largest species of sea turtles.
The leatherback species are not critically endangered like other species. There’s still some concern, but their numbers are higher than other species. Leatherback sea turtles reside in marine waters of the Atlantic, Pacific, and Indian Oceans. The nesting beaches in the United States are in Florida, Puerto Rico, and St. Croix. This sea turtle species was first recorded in 1761 in Djibouti waters.
Leatherback sea turtles look for prey like jellyfish, seaweed, fish, crustaceans, and marine invertebrates in coastal waters. They must watch for killer whales in the area because they will eat them as a snack. An adult leatherback sea turtle lives to 45-50 years old. Females lay their eggs at night on subtropical and tropical beaches.
Loggerhead Sea Turtle
Scientific Name: Caretta caretta
Other Names: Linnaeus
Size: 250 lbs
Distribution: Temperate subtropical and tropical areas of the Pacific, Atlantic, and Indian Oceans.
Loggerhead sea turtles get their name from their massive heads and strong jaws they use to feed on hard-shelled prey. Their diet consists of prey such as whelks and conchs. The sea turtle shells are hard and heart-shaped. They are reddish-brown on top with a pale yellow on their plastron.
The loggerhead sea turtle is not critically endangered, but their numbers have decreased from fishing gear like gillnets, trawls, and longlines. This sea turtle species was first recorded in 1758 by Carl Linnaeus.
There are only two loggerhead nesting beaches that have more than 10,000 female loggerhead sea turtles nesting per year. One is in Oman and one is in South Florida. Because of their long lifespan, a single female loggerhead sea turtle can lay up to 4,200 in a lifetime. This turtle species has a lifespan of over 70 years.
Adult loggerhead sea turtles do not have many predators. Humans and sharks pose the biggest threat. The eggs of a loggerhead sea turtle are in danger from hogs, crabs, fire ants, and raccoons. After hatching on the nesting beaches, the babies dash for the ocean. Many are eaten by fish and sea birds before they make it out to the far sea.
Green Sea Turtle
Scientific Name: Chelonia mydas
Other Names: Mydas
Size: 300-350 lb, 3-4 ft.
Distribution: Subtropical and temperate areas of the Pacific, Atlantic, and Indian Oceans and the Mediterranean Sea.
Green sea turtles are a dark brown, gray, or olive color. They have hard, bony shells that cover a light yellow-white underside. Their head has brown and yellow marks on it. Contrary to their name, green sea turtles are not always green. The best way to tell a green sea turtle apart from other species of sea turtle is their comparatively small heads.
These solitary, night-time nesters migrate thousands of kilometers between their nesting beaches and foraging grounds. Female adult green sea turtles mature at 25 to 35 years old. Their lifespan is over 70 years old. They eat mainly algae and seagrass. They also forage on sponges, discarded fish, and invertebrates. They find much of their prey in coral reefs.
Green sea turtles are a critically endangered sea turtle species. Overharvestation of their eggs, hunting of the adults, fishing gear mishaps, and loss of habitat all pose threats. The green sea turtle was first recorded in 1800.
Flatback Sea Turtle
Scientific Name: Natator depressus
Other Names: Flat back sea turtle
Size: 198 lbs, 3.25 ft.
Distribution: Tropical regions of the continental shelf and the coastal waters of Southern Indonesia, Northern Australia, and Southern Papua New Guinea.
The flatback sea turtle species have pale greenish-gray shells with outer margins that are abruptly upturned. As their name implies, their backs are flat relative to other sea turtles. Most of them have a curved carapace. They have the smallest distribution of all sea turtle species, breeding only in Australia.
An adult flatback sea turtle lives up to 50 years. The average clutch siz is 50-70 eggs. Many of these eggs will be eaten before they hatch. If the eggs do hatch and the young make it to the ocean, they are preyed on by saltwater crocodiles, large bony fish, and sharks.
Flatback sea turtles were first recorded in 1880 by an American herpetologist named Samuel Garman. This species of sea turtle has a diet of jellyfish, mollusks, sea cucumbers, prawns, seaweed, bryozoans, and other invertebrates.
Kemp’s Ridley Sea Turtle
Scientific Name: Lepidochelys kempii
Other Names: Atlantic Ridley Sea Turtle
Size: 75-100 lbs, 27-32 inches
Distribution: Gulf of Mexico and U.S. Atlantic Seaboard
The Kemp’s Ridley Sea Turtle species is the rarest species of sea turtle and is critically endangered. They are the in the highest danger of being extinct of all of the species of sea turtles in the world.
Kemp’s Ridley sea turtles have triangle-shaped heads with hooked beaks. Adult Kemp’s Ridley sea turtles are a grayish-green color on top and a pale yellow bottom shell. Baby Kemp’s Ridleys are dark in color.
They eat crabs, snails, shrimp, clams, jellyfish, sea stars, and fish. Their biggest threat is humans, sharks, sea birds, and other sea animals. Kemp’s Ridley sea turtles were first recorded in 1906. In 1970 they were listed under the Endangered Species Conservation Act.
Their lifespan is not known exactly, but it’s estimated to be around 30 years.
Hawksbill Sea Turtle
Scientific Name: Eretmochelys imbricata
Other Names: Tortuga-marina de carey
Size: 100-150 lbs, 2-3 ft.
Distribution: Tropical waters around the world
Hawksbill sea turtles have irregular shapes on their shells in shades of orange, amber, yellow, red, black, and brown. Overlapping scutes and serrated edges distinguish their shells from other species of sea turtles.
Hawksbill sea turtles are omnivores that prefer to eat sea sponges. They also eat marine algae, mollusks, corrals, crustaceans, tunicates, sea urchins, jellyfish, and small fish. They have predators like large fish, sharks, octopi, crocodiles, and humans.
Hawksbill sea turtles were first recorded in 1766. They were first listed under the Endangered Species Act in 1970. They live up to 60 years old.
Olive Ridley Sea Turtle
Scientific Name: Lepidochelys olivacea
Other Names: Pacific Ridley sea turtle
Size: 80-110 lb, 2.5 ft
Distribution: Tropical regions of the Pacific, Atlantic, and Indian oceans.
Olive ridley sea turtles have olive-gray shells. They are some of the smaller sea turtle species, weighing 80 to 100 pounds. They eat algae, crabs, lobsters, tunicates, and mollusks. They have to watch out for predators like sharks in the ocean.
Olive ridley sea turtles were first recorded by Georg Adolf Suckow in 1798. They are accidentally killed in mass by uncontrolled fishing around nesting beaches in their mating season. They were listed under the Endangered Species Act in 1978.
Sea Turtle Facts
Sea turtles are interesting creatures. Learn some quick facts about these fascinating sea animals below.
They don’t have teeth
Sea turtles use their beak-like mouth to grab their food.
Their young have mysterious lives
After hatchlings reach the ocean, the first few years are hard to study which leads to limited data.
Survival of the fittest
An estimated 1 in 1,000 hatchlings makes it to adulthood.
Female sea turtles always return to the same beach they hatched on to lay their eggs.
Sea turtles have some of the longest life spans for animals.
Sea Turtle Threats
All species of sea turtles face threats every day. Their home habitats are being disrupted by landfill waste. Leftover plastic and other non-biodegradable items get caught on sea turtles and cause health issues and death. Careless fishing raises the risk of harming sea turtles in their homes.
Frequently Asked Questions
Check out some questions commonly asked by others about sea turtles.
How much time do sea turtles spend on land?
Sea turtles spend two to five years on land.
Why can’t sea turtles retract into their shells?
There is not enough space in the shell for a sea turtle to retract.
How many eggs can a sea turtle lay?
Sea turtles can lay up to 110 eggs in one clutch and 4,200 eggs in a lifetime.
What was the oldest sea turtle ever recorded?
The oldest sea turtle recorded reached 83 years old.
Do sea turtles “cry”?
Sea turtles secrete urine through their eyes to remove excess salt.
How can you tell a sea turtle’s age?
After the death of the sea turtle, the humerus bone is examined. This bone reveals rings that allow the age of the turtle to be calculated.
All types of sea turtles have their own unique properties that distinguish them from other species. These graceful sea creatures are a favorite among many marine biologists. Their long life spans allow humans to develop a type of relationship with them.
Comment your favorite species of sea turtle below! Don’t forget to ask any questions you have about sea turtles so an expert can answer them.
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Specifically, my research investigates how the configuration and composition of landscapes influence the movement and population dynamics of forest birds. Both natural and human-derived fragmenting of habitat can influence where birds settle, how they access the resources they need to survive and reproduce, and these factors in turn affect population demographics. Most recently, I have been studying the ability of individuals to move through and utilize forested areas which have been modified through timber harvest as they seek out resources for the breeding and postfledging phases. As well I am working in collaboration with Parks Canada scientists to examine in the influence of high density moose populations on forest bird communities in Gros Morne National Park. Many of my projects are conducted in collaboration or consultation with representatives of industry and government agencies, seeking to improve the management and sustainability of natural resource extraction.