Skip to main content


By February 18, 2018November 11th, 2020Blog, Edutainment, Scuba, Siren Diving, Underwater Life

It’s A Moray!

Read at your own peril… you may not see Moray Eels the same again!

I’m pretty sure you’re all familiar with that incredibly shocking scene from the movie ‘Alien (1979)’ (If you’re not… please go and watch it before you continue reading!)… You know the one right? It was not long after first seeing Morays Eels on a dive and finding them incredibly creepy that I began to do some research. This lead me to discover some eerily ‘Alien’ parallels between Eels and that movie. Potentially Eels are where they originally got the idea for the Alien design from. Scared yet? Just wait… But before I totally freak you out about Eels, lets get to know them!

But what rEely are Eels?

An Eel (or Moray Eel) is a ‘snake like’ creature with a long slippery body that dwells in many marine environments around the world. Today I’m going to be talking about ‘Moray Eels’ which is a very common family of Eels you may see on your dives In Nusa Lembongan, Bali, Nusa Penida or perhaps on another coral reef around the world.

World wide there around 200 known species of moray eels. These include both true morays and snake morays which have different defining features.

Many Eels are more active at night and during the day you will find them hiding amount rocks and corals. Often you will just see the head emerging from its hidey hole and the length of its body will remain hidden. They feed on anything from small fish to crabs and other crustaceans.

Spotted moral eel

Size rEely Matters

Moray Eels vary greatly in size depending on the species but overall they are the largest type of Eel. They can grow up to a whopping 2.5m and weigh around 30kg! The largest known species is the Giant Moray (Gymnothorax javanicus) which is very common throughout South-East Asia and we meet them often on dives around Nusa Penida. These larger Morays may haunt a particular place for quite some time. For example there is a very large resident living at Blue Corner which can be spotted very often in the same place. These giants always remind me of the two Moray Eels, (Flotsam and Jetsam), that Ursular in ‘The Little Mermaid’ has as her pets.

Ursula from "The Little Mermaid"

Eel or Alien?

Like the monster in Alien, morays attack their prey with a secret set of toothy biters. Inside their throat are secondary pair of concealed pharyngeal jaws that help the eel capture its prey. Whereas most predatory fish use suction to swallow their food, morays instead rely upon a different strategy.

First, the outer jaws firmly grasp the terrified meal. Next, their secondary set of chompers shoots forwards, bites onto unfortunate victim, and pulls it into the throat.

Slightly terrifying for sure but fortunately, humans are not on their menu!

Diagram of eel jaws
pair of moray eels in a crevice

Hunting Buddies

It has often been noted that Moray Eels and Grouper can be seen hunting together. The sleek Moray Eel has the ability to move quickly through the coral and rocks. The Grouper is better skilled at speedy chases through open water so when they work together, their prey has no where to hide. To invite its Eel hunting assistant, the Grouper will first attract its attention with some ‘head banging’ movements. The hunt begins and the Eel will begin to wriggle its way through the jagged reef while the Grouper watches over head. In the end at least one partner gets a meal.

Don’t Judge a book by its cover

Eels may look and sound terrifying after you read about their secondary jaw. But be rest assured eels are not to be afraid of. They are very often mistaken as looking aggressive because they have the tendency to constantly open and close their mouth displaying their sharp teeth. This may seem like they have bad intentions but this is actually so they can breathe. Eels constantly open and close their moths to manually flush water through their gills. So don’t worry… this does not mean its getting ready to pounce! Attacks on divers are extremely rare as they are not aggressive by nature. There have been stories of silly divers feeding eels sausages and then the eel mistook the divers finger for another sausage… but lets not talk about that. As long as you give them their space, don’t touch and respect them as you should with any animal, you are really not at any risk.

Moray being cleaned by a shrimp
Picture of a snake eel

Eel or Snake?

Some eels such as the ‘Snake Eel’ (Myrichthys colubrinus) has specifically adapted its appearance to almost perfectly mimic that of the venomous Banded Sea Snake (Laticauda colubrina). With its cleverly disguised look, the Snake Eel is avoided by most predators. It allows it to hunt easily over sand areas near coral reefs for small fish and crustaceans without fear.

The Snake Eel just like the Banded Sea Snake has broad black and white bands along its body. In order to tell the different between the snake and eel variation is to check whether or not it has a fin down its back. The Eel will have a long thin fin running the length of its body, where as the snake will not. The snake will also have noticeable scales similar to that of a land snake.

Crossdressing Eels

There is a very special eel worth mentioning as it is one of my favourites. It goes by the common name of ‘Ribbon Eel’ (Rhinomuraena quaesita), as they do indeed look like a ribbon! (see video below) The incredible thing about Ribbon Eels is not only their funky appearance, but also their ability to change sex and colour throughout their life time. When they are in their juvenile stage, their are black in colour with a yellow stripe down the spine. At this stage in its life, the ribbon eel is a male. As the eel matures into an adult its body colour changes to blue. It can remain in this state for a few of years but at some point in its lifetime it will change into a fully grown adult female and will lose its blue colour and become completely yellow! Fascinating right?

F’eel’ing like a lover not a fighter

The video above is filmed at our very own Crystal Bay and shows an unusual interaction between 2 snowflake eels… Whether they are mating or fighting, it looks quite intense.

Thanks for reading we hope you rEELy feel educated and are not too scared to meet an Eel on your next dive!

Looking down the barrel of an eel
Brooke Pyke

Author Brooke Pyke

Turtle tickler and self proclaimed "Slugologist"

More posts by Brooke Pyke