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Garden eelsGarden eels Eels are snake-like fish that lack scales. There are around 800 species, ranging from some kinds just a few centimetres in length to the 3-metre (10-foot) giant moray. They have long, thin bodies with narrow dorsal fins that do not stick out from their bodies like those of other fish. Eels swim in a wave-like motion, called undulatory movement, that pulls their bodies into an S-shape (snakes move across land in a similar way). Eels live worldwide in oceans and rivers. Their young are called elvers.

Conger eel

Conger eelConger eelConger eels, which grow up to 3 metres (10 feet) long are bottom-feeders. They will often hole up in a wreck or rough ground and dart out to capture other, smaller fish in their powerful, teeth-lined jaws. Congers are mostly nocturnal feeders, but in darker depths of 20 metres (65 feet) or more they will seek prey at any time.

Diagram showing moray eel jawsDiagram showing moray eel jaws

Moray eel

Moray eels hide in holes between rocks or in coral crevices, waiting to shoot out and grab their prey—fish or octopus. The largest kinds of moray eel can grow up to 3 metres (10 feet) long. Morays have a second set of jaws in their throats. Called pharyngeal jaws, these are also lined with teeth. When feeding, morays launch these jaws into their mouth. These grab the prey and take it into the throat. Moray eels are the only animals that use pharyngeal jaws to capture prey.

Goldentail moray on the attack 

European eel

Eels were not known to be fish until the late 18th century.

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