Green moray

The green moray (Gymnothorax funebris) is a moray eel of the family Muraenidae, found in the western Atlantic Ocean from Long Island, New York, Bermuda, and the northern Gulf of Mexico to Brazil, at depths down to 40 metres (130 ft). With a length up to 2.5 metres (8.2 ft), it is the largest moray species of the tropical Atlantic and one of the largest species of moray eel known.^[2]

Green moray
At the ABQ BioPark Aquarium
Conservation status
Least Concern  (IUCN 3.1)[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Anguilliformes
Family:	Muraenidae
Genus:	Gymnothorax
Species:	G. funebris
Binomial name
Gymnothorax funebris Ranzani, 1840

A green moray on the sand bed at 110' near the artificial reef Eagle in the Florida Keys National Marine Sanctuary

The common name "green moray" is also sometimes used to refer to the yellow moray, G. prasinus. Its green colour comes from a protective layer of mucus secreted by its specialized goblet cells much like other species of moray. Underneath this mucus layer, the green moray eel is a darker color as can be seen in preserved specimens.^[3]

Green morays are typically not eaten and can cause ciguatera fish poisoning (CFP).^[4] Though the green moray is not considered endangered, moray eels in general are under-studied and often under-counted by traditional visual surveys.^[5][6] The green moray is rated as Least Concern by the IUCN, with no notable threats beyond occasional capture for public aquaria.

Behavior

Fish and crabs have been reported as gut contents in green morays.^[5] Many moray eels cooperate with other fish during hunting, and Brazilian snapper (Lutjanus alexandrei) appear to recruit green morays while foraging among mangroves.^[7]

Movement patterns

A 2021 survey used acoustic transmitters to track 16 green morays in the mangrove estuary of Salt River Bay, St. Croix. Green morays of this area appear to be mostly nocturnal: 10 were detected more often at night, 3 in the day, and 3 were too elusive to reliably analyze. Most eels had a home range averaging 5.8 hectares, with no correlation between an eel's size and range. 2 had broader ranges without a clear center of activity, and one moved to an adjacent bay during study.^[5]

6 eels emigrated towards offshore reefs and rocky submarine canyons, exiting the survey area. Each eel's emigration event took place over a single night in winter or spring, though it was preceded by some broader exploration of their bay of residence. The eels which emigrated were significantly larger (but not necessarily more mature) than those which did not.^[5]