Green Turtle 

Green sea turtles (Chelonia mydas), are named for the greenish hue of their fat, not their shells. Found in tropical and subtropical oceans around the world, these ancient mariners navigate vast distances, playing a vital role in the health of seagrass beds and coral reefs.

The adult carapace is smooth, keel-less, and light to dark brown with dark mottling, with whitish to light yellow plastron. From their remarkable migrations to their unique herbivorous diet, the story of the green sea turtle is one of resilience and adaptation in a constantly changing world. Let’s explore their fascinating world and discover what makes them so captivating.

Appearance 

Green turtles aren’t named for the color of their shells, which can vary. Instead, the name comes from the green tint of their body fat. Their shells are shades of brown, yellow, and even black.

These colors can change over time. For example, when green turtles are young, they usually have primarily black carapaces. But, as time passes, these light and turn a spotted/mottled pattern of browns.

They are shaped like most sea turtles. They have a flattened body with a shell, a short neck, and a beaked head. Its beak is shorter than other sea turtles, and it’s unhooked.

Green turtles are also unable to pull their necks and heads inside their shells. 

The plastron is yellowish and the limbs are usually also a similar color, lined with yellow. There may be a dark spot at the center of each appendage. 

On average, adult sea turtles grow to five feet, or 1.5 meters long, and weigh around 150-419 pounds or 68-190 kg. One specimen reaching 694 pounds was once recorded. The largest weighed 871 pounds, and its shell was 60 inches long. 

Habitat

Green sea turtles have a range that extends from the tropical and subtropical seas around the world. The largest populations are in the Atlantic and Pacific Oceans. These two populations of sea turtles are different from one another. They are genetically independent and have their own nesting and feeding areas. 

The largest populations around the United States are along the Atlantic coast, from Texas up to Massachusetts. There are Pacific populations along the southern California coast. Additionally, large populations can be found around Hawaii and Florida. Throughout the world’s oceans, sea turtles are most populous along the coasts of Australia, the Great Barrier Reef, and the Caribbean Sea. 

There are important green turtle feeding grounds around Florida, such as the Florida Keys and Cedar Key.

Green turtles generally make use of three different habitats. They utilize beaches to lay their eggs and spend most of their adult lives in the ocean shallows or in bays or lagoons. Seagrass meadows are a popular destination for sea turtles. 

Diet

Depending on their age, green turtles have different diets. Juveniles are carnivorous (eat jellyfish and other invertebrates) but become herbivores as they age. Their body fat starts to turn green as they move into eating sea grasses.

They are unique among sea turtles, eating mostly seagrasses and algae. This diet is what gives their fat a greenish color (not their shells), which is where their name comes from.

Reproduction

The mating season changes depending on the sea turtle population. Most mate between June and September, but other groups can be found mating from March to June, depending on the ocean temperature. 

The males and females find each other relatively close to shore, near or on the beaches where they were born.

Upon reaching sexual maturity, the female turtle mates and moves onto a beach above the high tide line and lays her eggs in a hole 11-22 inches deep. She covers the eggs (which can range from 85 up to around 200) with sand again. She then returns to the ocean, leaving the young to hatch and make it into the water on their own. 

A hatchling heads out to sea, where it lives for 5-7 years among free-floating mats of macroalgae like Sargassum.

Threats

Their primary threat are larger sharks and human beings. Tiger sharks are a common predator around the Hawaiian islands. As one would expect, younger, smaller turtles are generally at greater risk than mature adults. These smaller turtles may also be threatened by crabs and shorebirds. They also suffer from parasites, like barnacles and leeches. 

Historically, sea turtles have been used as a resource. Their skin has traditionally been used to make leather products, and their meat is considered a delicacy in some countries. Human activities, including poaching and egg harvesting, have been devastating to green turtle populations. Ingestion of marine debris is another threat to all species of green turtles. Other threats like boat strikes, pollution, and climate change have also influenced population numbers. 

Their global population decline has led to various countries taking major steps for their conservation. The killing of sea turtles has been strictly banned. Today, the IUCN considers all populations of sea turtles endangered. 

7 More Amazing Facts About the Green Turtle 

1. Green turtles are also sometimes known as black turtles or Pacific green turtles. 
2. They are the only species in the genus Chelonia. 
3. These reptiles are named for the color of their fat, not the color of their shells. 
4. They lay 85 to 200 eggs at one time.
5. The female turtle controls the mating process. 
6. Many countries, including the United States, prohibit the killing of sea turtles and the collection of their eggs.
7. Hotter, dryer sand negatively impacts the incubation of sea turtle nests and warmer nests produce more female hatchlings than males.

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