Marine Wildlife Encyclopedia
Spotted Moray Gymnothorax moringa
Species ID: M.GMb
Description: A medium-sized snake-like fish with a smooth, muscular body covered in many small, overlapping black and white spots with a pale to white belly. This moray eel has a fairly large mouth with many sharp needle-like teeth. The dorsal and anal fins are edged with black. Males and females appear similar
Maximum Size: 1 m (6 ft)
Longevity: Approximately 10 years
Status: Not currently on the IUCN endangered species list
Spotted Moray Eel & People: The spotted moray eel is of minor importance as a food fish. However, it is commonly caught in fish traps and sold locally on a small scale either fresh or salted. It is also occasionally sold as an aquarium fish
Geographical Range: Found throughout the Caribbean, Gulf of Mexico, north to the Carolinas and south to Argentina. Also found in the mid-Atlantic islands
Coral Reef Zone: Found in the shore, back reef, reef flat, fore reef and drop-off zones
Favourite Habitat: Spotted moray eels inhabit shallow reef areas, rock rubble zones and even sea grass beds.
Depth: 0–200 m (0–656 ft)
A Day in The Life
Dawn: Hunting activity decreases and moray eels retreat into the reef to hide
Day: During the day spotted moray eels hide within the structure of the reef at one of several shelter sites. Their head can often be seen poking from a reef crack or hole
Dusk: Spotted moray eels leave their daytime shelters and begin hunting for prey
Night: Spotted moray eels hunt actively on coral reefs and in seagrass beds
Who Eats Who?
Spotted moray eels are coral reef predators with a varied diet, feeding on fish (such as parrotfishes, grunts, trumpetfish and snappers), crustaceans (such as crabs and lobsters) and molluscs (such as octopuses). Spotted moray eels also eat carrion and are known to be cannibalistic. Only very large reef creatures, such as the dog snapper and Nassau grouper, are known to feed on this species.
Scuba Diver & Snorkeler Best Practices
Select environmentally friendly dive operations: Go ‘green’ when booking dive and travel plans—use companies that follow and promote ecofriendly practices, and abide by local laws and regulations like paying user fees for the use of Marine Protected Areas (MPAs). You may wish to investigate staying at a hotel that practices energy conservation, and recycles and treats waste in a responsible way. Select only dive businesses that follow a policy of best practices in all activities related to diving.
Spotted moray eels are relatively bold and easily approached, but will retreat into the reef structure if threatened. Hand-fed morays can become quite aggressive towards divers and snorkelers and may bite in search of food.
Spotted moray eels are carnivores that hunt actively at night. Hunting trips can last anywhere from one hour to the entire night and may take morays over 100 m (300 ft) from their daytime shelter. While hunting, morays use mainly their sense of smell to locate food, since their eyesight is poor. Morays often prefer hunting on nights when seas are rough and visibility is low, giving them an edge over their prey. Moray eels grab prey in their jaws and some attempt to hold and crush their meal by wrapping around it, just like constricting snakes do on land. Some fish species, such as coney, graysby and soapfish, have been documented following moray eels as they hunt at night. As the moray eels move, they flush fish and crustaceans out of hiding, and predatory fish that follow moray eels may benefit from a free lunch in the process.
Observe, record & share:
O M.GMb-101 – Hunting: Moray eels move over the bottom like a snake, looking for prey
O M.GMb-102 – Grabbing prey: Morays must get very close to prey before grabbing it
O M.GMb-103 – Holding and crushing prey: Moray eels may hold and crush their prey in their coils
O M.GMb-104 – Hunting with moray eels: Predatory fish may hunt alongside spotted morays
Attack & Defense Behaviour
Spotted moray eels are often seen with their head poking from crack or hole in the reef, and will retreat back inside it if they eel hreatened. Moray eels are generally loners that are virtually ever seen with members of their own species unless they are ating, but two eels may grudgingly share a hole if shelters are scarce. When attacked by a predator, an extremely agitated moray eel will vomit the contents of its gut to make it thinner and thus able to escape through narrower crevices in the reef. Morays need to open and close their mouth constantly to pump water through their gills. This apparent “biting” action is often interpreted as a threatening behaviour, but it simply their way of breathing. On the other hand, a moray eel that feels threatened may assume a warning posture where the jaws are held wide open and the upper body is arched slightly. If cornered and unable to escape, moray eels will bite to defend themselves.
Observe, record & share:
O M.GMb-201 – Breathing: Moray eels open and close their mouth to breathe
O M.GMb-202 – Retreating into reef: Moray eels retreat into their shelters when threatened
O M.GMb-203 – Sharing shelter: In rare cases, moray eels share their shelter with another moray
O M.GMb-204 –Warning display: If confronted, eels may hold their jaws wide open and arch their upper body slightly
OM.GMb-205 – Vomiting: Moray eels vomit in order to reduce their size and escape through narrower reef cracks
OM.GMb-206 – Biting: Moray eels will bite if provoked
Very little is known about reproduction in spotted moray eels, but their behaviour is believed to be similar to that observed in several other species of moray. From late fall to early spring, morays typically migrate to spawning grounds. Individuals take on spawning colours consisting of a dark back and pale belly. Male and female eels meet and intertwine so that their genital openings are close. The male may bite the female’s neck to hold on to her and ensure the pair remains in close contact. Eggs and sperm are released simultaneously into the water and disperse into the plankton. Eggs hatch after approximately 4-5 days, and the transparent, ribbon-like larvae may spend up to ten months in the plankton before settling onto the reef and taking on the appearance of the adult.
Observe, record & share:
O M.GMb-301 – Migration: Males and females are thought to migrate to established spawning grounds
O M.GMb-302 – Spawning colours: Individuals may develop a dark back and pale belly while spawning
O M.GMb-303 – Intertwining: Eels intertwine and the male may bite and hold the female by her neck in order to maintain close contact
O M.GMb-304 – Gametes: A cloud of eggs and sperm are released together into the water
Eel harassment: Vulnerable prey fish, such as butterflyfishes, parrotfishes and surgeonfishes have been observed displaying to moray eels and nudging or nipping them during the day, particularly at dusk. This “death wish” behaviour may even involve rubbing and bumping against the moray’s head . Strangely, the eels do not attack, but rather seem irritated and often swim away. Scientists believe that in harassing the moray eels, the prey fish are attempting to drive them away from the areas where they usually sleep at night, thereby making these areas safer. Morays also disturb other creatures as they move, which may result in them feeding, and a well-fed moray is safer for the organisms that remain. This kind of behaviour is also seen in birds that dive-bomb cats wandering too close to their nest sites.
Did you Know?
• Scientists recently discovered that moray eels have two sets of jaws. The main jaws are used to capture and hold prey. The second set of jaws, known scientifically as pharyngeal jaws, is launched once the moray eel has already caught its prey. This second set of jaws allows morays to drag prey into the throat without having to let go in order to reposition the prey for swallowing, as many predatory fish such as barracuda must do. By never letting go, the morays ensure their prey cannot escape. This unusual adaptation may sound familiar to people who have watched the film Alien, but this is not science fiction, it’s real life and right here on planet Earth!
What to do?
Share your observations today!: Discover your species of interest, observe its behaviour, and share your pictures and videos with friends and coral reef enthusiasts around the world! Upload media to the web, tagged with species common name (ex.: trumpetfish) and species ID code (ex.: A.AM) or species behaviour code (ex.: A.AM-101)