DIVE LOG Australasia

to the beach when they are ready to lay, and so they will often be tired even as they arrive. The experience only gets more tiring however as the female must pull herself up the beach, along with sometimes hundreds of other females that may have decided to lay on the same night. After a hunt for the right spot, the female will use their back flippers to dig a hole in the sand and then lay around 100 eggs. This exhausting exercise could potentially take her all night, so it is no surprise that this is often an elderly turtle’s last adventure. It is common to find tiger sharks around turtle nesting grounds. Once a female is back in the water, if she is old, she may then die from exhaustion or just get picked off by a shark that she would normally be able to avoid. The beach sees both the birth and often the death of a turtle. One of the largest green turtle nesting populations can be found in Costa Rica where some 30,000 females will nest each season, but they can also be found on beaches all around the world, either side of the equator. However The Great Barrier Reef boasts the largest on an island called Raine island. Raine Is. is only 32 hectares in size and yet each year, up to 60,000 green turtles will nest here. As it is one of the most important nesting sites in the world, you can imagine that it is

also monitored well. There are many studies done at Raine island and in 2015, the recovery project began to combat the effects of climate change. By bringing in 40 000 cubic metres of sand, it allowed scientists to reprofile the beach and so saving both the females and their eggs from drowning in the future as the beach was getting eroded. In many countries, it is not only the beaches that are in trouble but the turtles themselves. Due to many human factors such as entanglement, the introduction of pest species, bycatch and overfishing, there are many reasons that the populations of these beautiful reptiles are on the decline. There are many projects in the world that are looking at ways to reduce these impacts such as moving towards more turtle friendly hooks for fishing, devices that can exclude turtles from large fishing nets and prohibiting the killing of the adults and the taking of eggs. The next time you are in the water and see one of these wonderful creatures, think about where they came from. That beach that may seem like nothing of huge importance to you or me is the beginning and often even the end for the green turtle. Let’s do all we can to protect not just the animal itself, but the land on which it relies. And of course, don’t forget to say hi….

Coral Reef Macro herbivores.

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DIVE LOG Australasia #408 - October ‘24