Thornback Ray

A Thornback Ray being kept in the backroom tanks at London Aquarium.

The Thornback Ray is one of the most common rays in the world, encompassing a large area of the world, from Europe to South Africa, where it lives in shallow seas. Many are kept in the ray pools at the London Aquarium, where I spent a day as a Marine Biologist, including the Thornback Ray that I discovered there. You can recognise the Thornback Rays by the spiny ridges that run down their body from the middle of their back to the end of their tail. In terms of colouration, most rays have a number of pale spots on their backs, although the adolescent pictured above in more a matt brown colour. Females often develop spikes on the underside of their body as they grow older, and this is an easy way to sex the ray. Most rays measure at about 3/4 of a metre, although they have been known to reach lengths of just over 1 metre.

The Thornback Ray lives and feeds in the seabed, where it hunts down crustaceans like shrimp and crab, molluscs like sea snails and small fish which hide in the sand, which it grinds up with its plate like teeth. The camouflage on its back means that the ray is almost perfectly disguised from predators when it buries in the sand. Most sea animals have far less developed eyes than humans, and have to rely on other senses to find them. In order to find food themselves, the rays can sense the movement of sea creatures below the sand by the electric signals they produce,  allowing them to catch their prey even though they cannot see the sandy sea floor.

Many of these rays are caught every year by fishing trawlers, and passed off as skate for the fishing market. This repeated overfishing has left them in a near endangered state, so next time you order skate at a fish and chip shop, remember it could be a Thornback Ray instead.

I find rays to be really interesting animals, utterly different from any other creature in the world. I hope to come into contact with other types of ray in the future, perhaps some of the open water rays.

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