Cheloniida

© Christopher Hamilton 2011

Of the seven species of sea turtle worldwide, six are found in the waters of Australia’s Great Barrier Reef. Hatchlings emerge from leathery eggs buried in sandy beaches; the sex of the creature is determined by the how warm (resulting females) or cool (resulting in males) the temperature of the sand is. They are relatively long lived, with estimates ranging up to 80 years on average. Sexual maturity is reached earlier in some smaller species (12 – 30 years of age), but some larger species may take up fifty years to reach this point. Their diet varies amongst the species and generally includes sea grasses and algae, sponges, tunicates, jellyfish, crustaceans and small cephalopods. Some, such as the Green Sea Turtle begin life as carnivores and gradually switch to a herbivorous diet as they mature.