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A coral reef is a beautiful shallow water habitat. The warm water is home to many species of fish and invertebrates.

The daytime world of the reef is fascinating, but it is at night that it really comes alive. Nocturnal creatures emerge from burrows, ledges and other hiding places within the coral to search for food. As dusk approaches, coral polyps spread their delicate tentacles to capture tiny animals which dart through the water. Along the sandy bottom, the long body of a Moray eel slithers from a dark cave.

With beady eyes and snaggle-teeth, eels have been labeled a vicious predator that attacks both fish and people. Moray eels are nocturnal animals that live in the waters of the Indian, Pacific and Atlantic oceans. Eels range in size from 2-10 feet and the largest is the giant Moray which reaches 10 feet in length and weighs 75 pounds. Many have beautiful color patterns which help to camouflage them in the reef. Because Morays keep their mouths open almost all of the time the insides of their mouths are camouflaged also.

Morays have muscular, snake-like bodies with thick skin. They have no scales, but a layer of mucus covers the body and protects the skin from germs and parasites.

Because it is a night hunter with poor eyesight, the Moray relies on its keen sense of smell to locate prey such as damselfish and cardinalfish hiding in the coral.

Ledges and caves within the coral reef are the favorite dwelling places for the eel. Although it does not usually emerge during the daytime, divers often see the pointed face of a Moray sticking out of a cave with jaws open wide! While it may appear to be hungry and looking for a tasty morsel, this is hardly the case. A Moray must keep its mouth open constantly to take in water so that it can breathe. It has small spiral-shaped gills which pick up oxygen from the water. By opening and closing its mouth, the eel is able to pump water over the gills.

With its jaws open, it is easy to see the jagged teeth of the Moray which curve back into its mouth like sharp daggars. The curved teeth help to make sure that the slippery fish goes only one way - gulp, down the hatch!

Octopus Encounters

The octopus and Moray are deadly enemies. These two animals often encounter each other because they both like to live in the same kinds of caves on the reef and they are both nocturnal hunters. If a Moray smells an octopus nearby, it will poke its nose in to dark holes until its prey is found. Once located, the octopus is surprised by the Moray’s powerful jaws, which promptly clamp onto the soft body of the octopus.

The octopus will wrap its many tentacles around the head of the eel but to no avail. The slippery Moray will tie a knot in its tail and move the knot up its body until it has pushed the tentacles off. If the octopus is too big to swallow whole, then the Moray will eat it tentacle by tentacle. If the poor octopus is able to escape with some tentacles left, the missing ones will grow back. Morays can be quite efficient predators on a variety of prey. In addition to hunting for octopuses, they are good at squeezing their heads into small openings in the coral where small fish hide. They have also been known to hide in eelgrass beds and ambush unsuspecting reef animals. While they do not eat people, if provoked, they can do serious damage with their powerful jaws. Even though divers continue to report stories of “friendly” Morays, scientists still have much to learn about these secretive and unusual animals.