An ancient species
Turtles have been living in our waters for as long as 100 million years - that means they were around when Dinosaurs walked the earth! They even survived the meteorite impact that likely wiped out the Dinosaurs! As a result of this, they have evolved some incredible adaptations that allow them to survive in the vast, salty ocean; they can obtain fresh drinking water from the salty sea water by excreting the excess salt through a special gland in their eye! When the females are on sandy beaches laying their eggs, this gland also helps flush the sand out of their eyes.
The perfect temperature
When a female lays her eggs, the temperature of the nest will determine whether the hatchlings are boys or girls: warmer nests produce more females and cooler nests produce more males. Once the hatchlings leave their nest and venture out into the open ocean, they are able to use the Earth’s electromagnetic field to return to the same nesting grounds they were born at.
Marine turtles have played vital roles in maintaining the health of the world’s oceans for more than 100 million years, including maintaining the health of sea grass beds and coral reefs, providing key habitat for other marine life, helping to balance marine food webs and facilitating nutrient cycling from water to land. Marine Turtles even improve our iconic beaches by supplying a concentrated source of high-quality nutrients to their nest site. These nutrients aid the growth of vegetation and help to stabilise important sand dunes. Additionally, they are an integral part of the traditional culture of many coastal indigenous peoples throughout the world.
A threatened future
All marine turtle species are experiencing serious threats to their survival. The main threats are pollution and changes to important turtle habitats, especially coral reefs, seagrass beds, mangrove forests and nesting beaches. Other threats include accidental drowning in fishing gear, over-harvesting of turtles and eggs, and predation of eggs and hatchlings by foxes, feral pigs, dogs and goannas.
Marine turtles have a toolbox of amazing adaptations that help them survive:
- Marine turtles migrate long distances between their feeding grounds and nesting sites
- They have a large shell called a carapace, four strong, paddle-like flippers and like all reptiles, lungs for breathing air
- The characteristic beak-like mouth is used to shear or crush food
- Turtle’s shells look a little like human body armour, so one might conclude that they're reptilian versions of the powered exoskeleton that makes Iron Man such a fearsome superhero. But the shell, which is made up of about 50 different bones, actually is an evolutionary modification of the rib cage and part of the vertebral column
Come and meet us
While Taronga does not have any marine turtles on permanent display, we are committed to their conservation in their natural habitat; particularly through our rescue, rehabilitate and release program.
The Taronga Wildlife Hospital at Taronga Zoo Sydney treats an average of 40 marine turtles each year that have been washed up on beaches or found floating, in the ocean unable to dive. Rehabilitating and releasing these animals is a priority of our staff. Once admitted to the Taronga Wildlife Hospital, the turtles are given a full veterinary examination, radiographed, have blood tests and in many cases need to spend weeks in intensive care to ensure their survival. When well enough to clear intensive care, they are moved into rehabilitation pools to prepare for release. This involves eating well, gaining weight and swimming and diving proficiently.