Having watched far too many “Sea Hunt” episodes, during which Mike fought for his life against a crazed Moray eel, my first close encounter with an eel went none too well. Surf casting off Pompano Beach one evening, I reeled in a small eel. Without pause, I flung new pole and all back into the surf as I screamed bloody murder and ran for safety. Tearing through well-trimmed shrubbery I was grabbed by the elderly caretaker who came running when he heard my screams.
Once Walter determined that all my limbs were attached and nothing dreadful had happened to me, he managed to decipher from my hysterical 13 year-old babbling that there was an eel on the end of a line attached to a pole somewhere in the Atlantic. After wading around a bit, old Walter came up with my surf-casting outfit, the eel still attached. Walter’s eyes lit up…dinner!
My next close encounter with an eel came many years later when my dive buddy, (the same one who had me wriggling into a hole in a reef to see the Channel Clinging crab in last month’s article,) signaled for me to ease up under a mammoth mushroom-shaped rock at the base of a wall off Roatan. No sooner had I made my way under than I was bowled backwards by an escaping Green Moray whose daytime hidey-hole had been disturbed. My buddy and I followed along at a distance, up and over the top of the wall until he found another lair—where we left him in peace.
Shy and mainly nocturnal, there are approximately 200 species of moray eels throughout the world’s tropical waters and coral reefs, living and hunting in depths ranging from a few feet to over 500 feet. Their lengths range from less than a foot to over 15 feet with a girth of well over a foot in some of the largest species. Their coloration and skin patterns vary widely and run the gamut from the Ribbon eel with its bright blue body and yellow dorsal fin to the brown and white polka-dotted Spotted eel. The large Green Moray only appears to be green; a thick layer of yellow mucus protects his beautiful turquoise blue skin—and yellow and blue make green.
The Morays’ reputation for being vicious and aggressive seems to stem from their perpetually gaping jaws. What most do not realize is that they are not threatening to attack but merely breathing; pulling in water to filter over their small, roundish gills located much to the rear of their mouths.
Like all wild animals, Morays will defend themselves if stepped upon or harassed and yet many, once habituated to divers or swimmers, have learned to accept petting and hand-feeding—although this author does not recommend either since the eels’ poor eyesight has led to unintentional bites. While the bite of a Moray is not venomous as many believe, bites can lead to severe infection due to the number of deep wounds the teeth can inflict, teeth that are coated with quite nasty bacteria.
After I made several visits to a secret location I dubbed Eel Rock, often finding three or four species of Morays in residence at once, the eels became so accustomed to my presence that it was not out of the ordinary for one or two to swim back and forth across my body as I lay on the bottom photographing the others.
Their vision is lacking as is their hearing, however, their sense of smell is acute. Their elongated heads carry two pairs of nostrils; the forward tube-like protruding nostrils on their snouts take in water to test for scent while the second set of nostrils above the eyes provides the exit for the scent-tested water. The eels’ narrow heads and small eyes make them appear to be a bit cross-eyed. The narrowness of their heads makes it impossible for them to create the negative pressure required to swallow their food in the same manner as fish—or humans, for that matter.
Instead, Moray eels’ first, and visible, jaws are filled with long needle-like teeth that curve backwards toward their throats; teeth designed for holding prey rather than ripping and tearing. Located in their throat area is a second set of jaws lined with similar teeth, the pharyngeal jaws. Once the visible set of jaws snatch a meal, the pharyngeal jaws in the throat extend forward and pull the prey into the digestive system.
The Morays’ diet consists of reef fish, other eels, crustaceans, mollusks, octopus, squid and cuttlefish. While there is some commercial eel fishery, they are known to carry ciguatera since they feed upon reef fish—so eating them is not advisable. Other than man, the Morays’ main predators are barracuda, grouper, and other eels.
While grouper will take Morays and vice versa, Swiss scientists studying fish behavior in the Red Sea unexpectedly discovered an activity thought only to occur among humans…cooperative hunting between two species. Much to their surprise, the scientists watched as a grouper approached a Giant moray resting in a reef crevice. Fully expecting a fight, they were amazed as they watched the grouper shake its head from side to side, the eel emerge, and the two swim off together in search of prey in crevices too tight for the grouper to enter. In the December, 2006, issue of Public Library of Science Biology, the scientists reported that the groupers and eels actually took turns eating the prey they hunted cooperatively.
One of the scientists who discovered this cross-species cooperative hunting, Redouan Bshary, a behavioral ecologist with the University of Neuchâtel in Switzerland, summed up their discovery. "The most important implication is that there are still so many surprises to be discovered in coral reefs." How very true.
After 30 years as a wild and domestic animal rescuer, rehabber, and educator in the states, Becky Dayhuff-Bauer became a scuba instructor and award-winning journalist covering the marine environment in the Caribbean. She is a contributing photographer to NOAA.