Some new rays were found by our experienced collections team at the end of February, but to ensure they were healthy they have been kept in quarantine until now. At long last they have moved into their new home in our ray pool in the Atlantic Ocean Gallery.

What is a ray?

The flat teeth and jaw structure of a stingray. By Autopilot (Own work) [CC BY-SA 3.0], via Wikimedia Commons

Rays are cartilaginous fish, the same class of animal as sharks, but fall into a group called batoids – literally meaning “bat-shaped”. This is because the one thing that all 600-plus species of rays have in common is large, flat bodies and heads that are fused with their pectoral fins, giving them their characteristic shape.

Most rays like to live near the sea floor, hunting for small prey that they then crush with their rounded teeth.

What’s special about eagle rays?

Weighing in at half a kilogram each, our eagle rays (Myliobatis aquila) are small, but they can grow to be almost 15kg and 1.8m long. Ranging from the UK to South Africa in the Atlantic and from South Africa to Kenya in the Indian Ocean, the common eagle ray spends its life exploring shallow waters, up to 30m deep – constantly on the hunt for mussels, crabs and other shellfish that it can catch and crush with its powerful, flat teeth.

The common eagle ray Myliobatis aquila

Eagle rays are easily distinguishable by their diamond-shaped bodies and their long tails. This shape, together with their inherent bravado, allows eagle rays to jump metres out of the water when threatened. They also like to fold their fins upright, looking like two sharks swimming side by side. Despite their speed and appearance, they are gentle and pose little risk to humans – just be careful of their defensive tail spine.

A spotted eagle ray (Aetobatus narinari) uses its speed and agility to leap from the water and avoid becoming a snack. Credit: Ralphe Bie/Caters News

Why are blue stingrays amazing?

Although our new blue stingray (Dasyatis chrysonota) is quite a bit larger than the eagle rays at 1.8kg, it can only grow to be about 75cm. They are found in the waters around South Africa and Mozambique, and can be found to a depth of about 100m. Like the eagle ray, they are on the hunt for small crustaceans and molluscs, but they also have some sensitive electrical receptors that allow them to find prey beneath the sand.

The mottled blue smudges of the blue stingray help to obscure it from vision when viewed from above.

Blue stingrays rely on their awesome blue-mottled camouflage to stay safe, thus they do not need the speed and strength of the eagle rays. These stingrays have also adapted to match their surroundings closely. This is abundantly clear in our ray pool, where the new blue stingray is significantly darker in colour than the two that have been living in there for a while. The lighter colour favours the sandy environment in this case.

Both of these are blue stingrays. The older one on the right has adapted to blend into the sandy bottom. The newcomer on the left, unfortunately, is a little out of place.

Their reliance on camouflage also leads to some behavioural differences; you’ll see our blue stingrays hugging the bottom of their pool, sometimes covering themselves in sand. By contrast, the eagle rays often keep some space between themselves and the sea floor, always ready to swim away quickly.

Which of these rays is your favourite? Whichever you settle on, remember to pay these newcomers a visit on your next trip to the Two Oceans Aquarium.

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