By Peter Frost
Imagine the scene. It is August 1988 on a holiday beach near Harlech in Wales. A huge beast has washed up on the beach. It is nearly the size and shape of a Volkswagen beetle car.
In fact it is a leatherback turtle. And at just under ten foot/3m long nose to tail, and weighing in at just under a tonne it is the biggest leatherback ever seen anywhere in the world.
The leatherback sea turtle (Dermochelys coriacea), sometimes called the lute turtle, is the largest of all living turtles.
Unlike most other sea turtles it has no bony shell. Instead, its carapace is covered by oily flesh and tough leathery skin.
Today sightings of leatherback turtles are increasing all around the Welsh coast and in south-west England. They are are drawn here by the high numbers of jellyfish - the main diet of these huge marine reptiles.
Sadly many turtles risk death or serious injury by mistaking the many polythene bags and other plastic litter that floats in the sea as its jellyfish diet.
The leatherback turtles lay their eggs on Caribbean beaches before crossing the Atlantic Ocean to feed in Welsh coastal waters.
To those lucky enough to spot one they are one of the most spectacular species to visit our coastal waters.
On inland waters too turtles and terrapins are becoming more and more common. There is a healthy colony at the London Wetland Centre at Barnes.
I often see them in the ponds at Cambridge University botanical gardens.
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