Green Sea Turtle

Green Sea Turtle facts at a glance

How big is a green sea turtle?

An adult green sea turtle measures 1.5 m long — about 87% of the height of an average adult person (1.73 m) — and weighs around 160 kg, about 2.3× an average adult’s body weight (70 kg).

What is a group of green sea turtles called?

Explore more animal collective nouns and baby animal names .

Behavior and migration

Green sea turtles undertake some of the longest migrations of any reptile, traveling hundreds or thousands of kilometers between feeding areas and nesting beaches. Remarkably, females return to the very beach where they hatched to lay their own eggs, navigating using the Earth's magnetic field.

Diet

Hatchlings and juveniles eat a mix of animals and plants, but adults switch to a largely herbivorous diet of seagrass and algae. This grazing keeps seagrass meadows healthy, making green turtles important to coastal ecosystems.

Habitat and range

Green sea turtles live in tropical and subtropical waters around the world, favoring shallow coastal areas with seagrass beds and coral reefs. They come ashore only to nest, with females digging nests on sandy beaches at night.

Conservation

Green sea turtles are assessed as Least Concern globally in the 2025 IUCN assessment, following decades of conservation. Some regional populations remain threatened. They face threats from hunting, egg collection, accidental capture in fishing gear, plastic pollution, and the loss of nesting beaches to coastal development and rising seas. Protected nesting sites and fishing regulations are helping some populations recover.

One turtle, several habitats and life stages

Green turtles use different habitats as they grow and may travel long distances between feeding and nesting areas. Protecting a nesting beach alone cannot address every threat encountered at sea. Entanglement, vessel strikes and loss of suitable habitat can affect survival. Conservation labels also need context: a national legal listing, a regional population and a global Red List assessment are not interchangeable.

Did you know? Green Sea Turtle facts

• Adult green sea turtles are unusual among sea turtles in being largely herbivorous.
• Their diet of seagrass and algae is what gives their body fat a greenish tint.
• They can migrate thousands of kilometres between feeding and nesting beaches.
• Females return to the very beach where they hatched to lay their eggs.
• The temperature of the nest determines the hatchlings' sex.
• Green sea turtles are Least Concern globally (IUCN 2025); regional threats from bycatch, hunting and habitat loss remain.

Diet & feeding

Adult green sea turtles are mainly herbivorous, feeding on seagrasses and algae, while juveniles are more omnivorous, taking invertebrates as well.

Adaptations

• Finely serrated jaws are suited to cropping seagrass and algae.
• Streamlined shells and flipper-like limbs make them efficient long-distance swimmers.
• Salt glands near the eyes excrete excess salt from seawater.
• Natal homing guides females back to their birth beach to nest.

Behaviour & ecology

• Green turtles graze seagrass meadows and algae beds as adults.
• They undertake long migrations between feeding grounds and nesting beaches.
• Females come ashore to dig nests and lay clutches of eggs at night.
• Hatchlings rush to the sea and spend early years in the open ocean.

Communication

• Sea turtles rely mainly on vision and chemical cues rather than vocal signals.
• Hatchlings use light and slope cues to find the sea.
• Adults navigate using Earth's magnetic field on long migrations.

Habitat & range

Green sea turtles inhabit tropical and subtropical coastal waters worldwide, grazing in shallow seagrass and algae habitats and nesting on sandy beaches.

Ecological role

As grazers of seagrass, green turtles keep meadows healthy and productive, supporting fisheries and carbon storage, and they cycle nutrients between sea and beach.

Conservation status of the Green Sea Turtle

Sources & references

This guide is compiled and reviewed against established zoological and conservation references. Key sources for the Green Sea Turtle:

• IUCN Red List of Threatened Species

  Conservation status (Least Concern) reflects the IUCN Red List category for Chelonia mydas, most recently assessed in 2025.

• iNaturalist — observations & photos

  Search citizen-science observations and community IDs for Chelonia mydas. Useful for range checks and recent sightings — not a substitute for formal Red List status.

• GBIF — occurrence data

  Global Biodiversity Information Facility species search for Chelonia mydas. Explore published occurrence records used in range research.

• IUCN SSC Marine Turtle Specialist Group — Green turtle assessments (2025).

  Global Least Concern status and distinct regional assessments; checked 19 September 2026.

• The Reptile Database (reptile-database.org).

  Taxonomy and distribution.

• Animal Diversity Web — Chelonia mydas. University of Michigan Museum of Zoology.

  Life history, morphology, and range.

• Global Animal Guide editorial standards

  How we research, source, review, and update every guide for accuracy.