Roger Touv, Age 11, Of Richmond Hill, Ont., Canada, for his question:
What is a sting ray?
The ray fishes enjoy life in the coastal waters of temperate and tropical seas. Some you might mistake for flounders, dozing on the sandy floor of the shallow tidal waters. Others you might mistake for monstrous sea going bats, swimming through the ocean by flapping their giant wings. Some rays have snaky tails and stingers that might remind you of the poisonous vipers.
The rays are flat fish, though they are not related to the soles and the Flounders. Their remote ancestors gave rise to the sharks, the skates and the Sawfishes. All these fellows have skeltons made from gristle or cartilage. They belong in the class chondrichthyes meaning the cartilage fishes. In place of fine., glassy scales, the cartilage fishes have small bony plates embedded in the slimy skins. Instead of having bony gill covers, their gills open to the water by a series of clefts or slits. Gristle fish of many kinds thronged the ancient seas before the first bony fishes appeared. About 150 million years ago, Certain gristle fish adapted to life on the ocean floor and became the ancestors of the many rays that live in our warm and temperate waters.
These fish that flopped to the floor of the sea became flat, their fins fused Together and their bodies took on a pancake shape. Some kept their fishy tails, Others developed whip tails. The sting rays are whip tailed gristle fish, and their Tails are armed with deadly sharp daggers. The spears sprout about half way down the tail, and there may be one or several of them.
Several of them sting rays come in assorted sizes, and they tend to prefer life in the tropics. Some of them are no bigger than pancakes and many are six feet long, and a sting ray who lives in Australian waters may be 12 feet long. The rays still like to doze on the sea floor, half buried in the sand. Their gristly sides act like wings which they can flap. When they swim, they glide through the water like slow moving bats.
The sting of the sting ray is a painful and a dangerous wound. When threatened, the flat fellow swings his barbed tail, around to stab his enemy. Mucus from his slimy body is injected into the wound along with sea water. Both the mucus and the sea water tend to poison the deep wound, and the patient should be treated by a doctor.
Swimmers and divers in tropical waters should avoid the sting ray, but this is not always possible. A bather may step accidentally upon a small spotted sting ray half buried in the sand. A skin diver may provoke a large sting ray as the big fellow glides gracefully through the water. When he attacks, the ray swings his tail around and drives his barbs deep into the flesh. The painful wound is slow to heal and without treatment may be fatal.