All marine turtle species are experiencing serious threats to their survival. Marine turtles are recognised internationally as species of conservation concern as in Fiji, with a survival rate of 1 in every 1000.
Marine turtles found in Fiji include:
- Hawksbill turtle (Eretmochelys imbricata)
- Green turtle (Chelonia mydas)
- Loggerhead turtle (Caretta caretta)
- Leatherback turtle (Dermochelys coriacea)
Turtles start life on a beach as a hatchling, measuring no more than the length of a ring finger.
During the night in what is known as the “hatchling frenzy”, the individuals clamber over each other to reach the surface of their nest and rush toward the sea using the horizon’s light as a cue.
At this point they encounter one of the many challenges to their survival, natural predators like crabs, ants and birds. Another encounter is the confusion from artificial lights emanating from roads or buildings which they mistake for the horizon and the water’s edge.
Hatchlings that make it to the surf line keep crawling until an undertow sweeps them out into deeper water where they then set a course for the open ocean for a 96 hour non swim. Once they are in the open ocean young marine turtles then depend on ocean currents to freely drift and feed until they are a size of dinner plate at which time they tend to settle at inshore feeding grounds.
Marine turtles grow slowly and take between 30 to 45 years to reach sexual maturity. They live for years in the one place before they are ready to make the long breeding migration of up to 3000 kilometres from the feeding grounds to nesting beaches.
When breeding, nesting females return to the same area thought to be in the region of their birth. As hatchlings they become imprinted to the earth’s magnetic field and possibly the smell of the waters adjacent to the nesting beach which allow them to successfully complete their migration.
Courtship and mating take place in shallow waters near the nesting beach. Females often mate with more than one male. After mating the males return to the feeding grounds.
Between nesting efforts, female turtles gather adjacent to the nesting beaches. They return to the same beach to lay consecutive clutches. A female green turtle usually lays six clutches of eggs at two weekly intervals, with each clutch containing about 100 white, spherical, “ping-pong” ball sized eggs.
After laying its eggs, the turtle then fills the egg chamber with sand using the hind flippers and then fills the body pit using all four flippers before crawling back to sea. And then it is another wait before the next generation of hatchlings run down to the beachfront for another whole new cycle of life.