Anyone who has visited an aquarium worth the salt in its water has likely come face-to-face with a moray eel. They are fearsome-looking creatures, equal parts snake and sea monster, and are often as big a draw for aquarium-goers as sharks or sea turtles. In Charleston, South Carolina's new city aquarium, a green moray eel named Chuck has a tank of honor in the entry hall, around which on any given day throngs of squealing schoolchildren congregate. Chuck elicits a combination of dread and delight that children find irresistible, and no wonder: his gaping mouth showcases rows of needle-like teeth, his unblinking, dispassionate eyes are the underwater equivalent of Hannibal Lecter's, and at feeding time a brave diver goes into the tank and feeds Chuck a healthy, bloody combination of shrimp and fish. Chuck is marine life at its best - slimy, pea-green, and toothy.
Though all are members of the family Muraenidae, there are more than one hundred individual species of morays. Common morays in the Caribbean reefs include the spotted, goldentail and green morays. The largest is the giant moray, which can grow to lengths of ten feet and weigh as much as seventy-five pounds, but the average adult moray eel is generally between three and four feet long. Unlike many fish, morays lack scales and gill covers. Instead of scales they have a thick layer of yellowish mucus that acts as a lubricant. This protects their bodies from scrapes, since they live most of their lives in cramped, rocky caves. Because they lack gill covers, morays must draw water into their mouths and over their gills, thereby continually exposing rows of snaggly, razor-sharp teeth. This Dracula-like display of fangs may be the reason they've earned an entirely unwarranted reputation as aggressive predators, but nothing could be further from the truth. Docile, intelligent, and affectionate, morays are actually curious (if relatively shy) nocturnal creatures. Seasoned divers have struck up long-standing relationships with morays, who seem to look forward to visits from their fish-bearing friends.
Because they live in caves and crevices, morays will bite if startled, but there has never been a documented report of an unprovoked moray attack on a human. Though the bites are extremely painful and jagged, most people recover with antibiotics and a few days out of the water. Octopi, however, are another story; since both are reef-dwelling nocturnal predators, octopi and morays are mortal enemies competing for the same food. Morays have poor eyesight but an excellent sense of smell, and when one sniffs out an octopus it will nose about its territory until it finds the intruder. Once it finds the octopus, the moray will clamp down on the octopus' soft body and shake it as a bulldog shakes a rabbit. When the octopus desperately wraps its tentacles around the moray, the eel will tie its body into a knot around the octopus and work the knot upward, ripping off the octopus' tentacles. Once the moray has a good grip, the octopus doesn't stand much of a chance.
Morays are true gourmands, feasting on vertebrates and invertebrates alike, but they prefer small reef fish. Some species (like Chuck, the green moray) have a third row of teeth on the roof of their mouth that curves inward to insure that the slippery prey goes smoothly down the gullet. Others (such as the chain moray) have flatter teeth designed to crush crabs and sea urchins. They are exclusively nocturnal predators, and rarely venture from their coral enclaves in the daytime. Five species of moray are known to be poisonous, and because they are considered a great delicacy in Italy, China, and Japan more people have died from eating the "wrong" kind of moray than have ever died from moray attacks. The very first salt water fish-breeding tanks were designed in ancient Rome to raise morays, which were a favorite of the caesars. Morays are said to have a delicious chicken-like flavor, but the tough skin must be removed because its mucus contains noxious oils.
Morays begin as a tiny planktonic larva called a leptocephalus. Leaf-shaped and translucent, the three-inch-long leptocephalus drifts for eight months with other plankton until it reaches the juvenile stage of development. It then stakes out a nice secluded cave and grows at a slow rate. A two-year-old specimen is generally about one foot in length. The life span of the moray is thought to exceed thirty years; one pair lived to be twenty-seven in captivity, and morays have no known natural predators. Relatively little is known about morays, particularly with regard to their breeding habits, and research is ongoing.