Green sea turtles Live to over 80 years in the wild. The green sea turtle is also known around the world as the green turtle, the black sea turtle or the Pacific green turtle.
From 5cm at birth to 1.5m fully grown, green sea turtles are the second largest of the sea turtles behind leatherback turtles.
The name however doesn’t come from the colour of their shell, which is generally olive to black in colour; these turtles are named after the fat that lays underneath the carapace which has a green hue.
Migrating long distances from feeding grounds to hatching areas, green sea turtles are listed as endangered or threatened in many countries.
This often due to human activity such as being hunted for food, pollution and being caught in fishing nets.
They often suffer from habitat loss in areas due to growing real estate development taking over their traditional nesting grounds.
The green sea turtle generally live 80 or more years in the wild, and can take anywhere between 20 – 50 years to reach sexual maturity.
This means a female green sea turtle may not lay her first clutch of eggs until she is 35 or older.
While male turtles can breed every year, the females only breed every three to five years.
The green sea turtle can lay anywhere between 75 – 200 eggs in each clutch, and can lay numerous clutches before leaving the nesting areas.
Eggs take around two months to hatch and then make their way to the sea. Like any other sea turtle, only a percentage make their way to the ocean, and only a small percentage make it to being an adult.
What Do Juvenile Green Sea Turtles Eat?
Juvenile green sea turtles tend to be omnivores and eat a wide variety of plants and animals. Such as insects, crustaceans, seagrasses and sea worms.
On the other hand adult green sea turtles eat seagrass and algae. Adults are herbivores and spend their eating hours cropping the seagrasses and eating algae. With a serrated jaw, they are more suited to the vegetarian lifestyle.
Australian Geographic notes that in 2011 scientists started using satellite tags to follow the movements of two young green turtles in the waters off Port Stephens in NSW.
It was found that, along with foraging, nesting and migrating in the tropical regions of northern Australia, young turtles drift into more temperate waters to take advantage of feeding on seagrass and invertebrates.
Interestingly, green sea turtles nest on the very same beaches they themselves hatched on years earlier.
Green Sea Turtle Predators
Green sea turtles have predators no matter how old they are. The main predator for adults are large sharks, particularly tiger sharks. Killer whales are also known to predate on green sea turtles.
For hatchlings and eggs, the predator list grows – fish, dogs, birds, ghost crabs, lizards and more.
It has been estimated that the rate for baby green sea turtles to make it to adulthood is 1 in 1000.
Living Near Rookeries
If you live near a turtle hatching area, anywhere in the world, it’s important to know when your local nesting and hatching seasons are.
One of the biggest threats, especially to hatchlings, is light. Hatchlings use the light of the moon to guide the way to the water. And the light from buildings near the nesting areas, can distract the hatchlings and they start to crawl away from the water, making them more susceptible to predators.
Other major factors when it comes to green sea turtle deaths are by-catch by trawlers, marine debris and pollution, disease, strikes and cuts from boats and propellers, hunting, and changes in the temperatures between nesting beaches and marine habitat.
Green Sea Turtle Breeding & Rookeries
Green sea turtles are threatened the world over and there are only a few large nesting populations left.
Here in Australia we have some of the largest nesting areas in the region for many marine turtle species including the green sea turtle.
Green sea turtles make their habitat around coral reefs that are rich in seaweed and near seagrass pastures in tropical and subtropical regions.
The main population of green sea turtles in Australia occur in the southern Great Barrier Reef, the northern Great Barrier Reef, the Coral Sea, the Gulf of Carpentaria, the north-west shelf of Western Australia, Ashmore Reef, Cartier Reef and Scott Reef.
Major rookeries (or nesting areas) in Australia occur in the Southern Great Barrier Reef area. Nesting and hatching occurs from mid-October through to early-April with the peak being in late December through to early January.
Places such as Mon Repos near Bundaberg offer the potential to see nesting and hatching green sea turtles.
Where To See Green Sea Turtles
There’s numerous places to see green sea turtles right here in Australia and across the world. In Queensland, try Heron Island, Mon Repos; in Western Australia try Ningaloo Reef; while in the Northern Territory, Bare Sand Island is a popular location.
According to the Department of Environment and Energy, Western Australia has one of the largest remaining green sea turtle populations in the world, estimated to be in the tens of thousands.
The Lacepede Islands in Westerns Australia are one of the most critical nesting areas, supporting the largest green sea turtle rookeries in the state.
In the United States, you will find green sea turtles on the Hawaiian islands, the Virgin Islands, Puerto Rico and Florida’s east coast. Other areas include Georgia, South Carolina and North Carolina along the Atlantic coast
In 2016 ABC reported on the Raine Island Recovery Project – raising the height of a remote, inaccessible to the public island off the far north coast of Queensland to help save the nesting site for thousands of turtles.
This island, located about 620km north-east of Cairns, is the nesting ground for approximately 60,000 green sea turtles each year, and researchers have been reshaping sections of the beach to help protect the breeding grounds, as well as keeping the island safe for green sea turtles.
Through conservation efforts such as the Raine Island Recovery Project it is hoped that the number of green sea turtle hatchlings increase in the coming years.
Green sea turtles play an important part in the marine world and there are plenty of ways you can get on board to help conserve this species across the world.