Moray eels are not related to the better known British species such as the common eel and the conger eel.
Their distinguishing feature is a remarkably sharp set of teeth, and they are unique because – unlike other eels – they don’t have any pectoral fins.
Powerful and colourful, morays, in their native waters at least, can reach up to 1.5m (5ft) long. Their skin is basically dark brown, marbled with yellowish, and in some cases purple, blotches. The body is flattened from side to side – not rounded like that of most shallow-water eels.
Although they are common fish in the coastal waters of southern Europe and in the Mediterranean, they occur only rarely off Britain and northern Europe.
In the past moray eels have been infrequent visitors to British shores — not as a result of any deliberate migration but merely a case of the odd specimen wandering away from the main population.
But today, as a result of changes in the sea’s temperature (an advance effect of global warming), tropical and sub-tropical species like the menacing moray are occurring in increasing numbers in Britain’s temperate south coast waters.
Quick reef eel
Adults spawn in the summer (July to September in the Mediterranean). Once the eggs hatch, morays like all eels go through a juvenile life stage as transparent larvae, floating at the surface of the sea. By December the young can reach up to 13cm (Sin) long and it is at about this time that they begin to become coloured and live on the sea bed.
They take up life in holes and crevices in rocky areas, and despite their ferocious character, appear very shy when approached by divers, retreating into the safety of their holes with just head and ‘shoulders’ visible.
In southern European waters morays live among rocky reefs, boulders and – like the conger eel – in the crevices of wrecks. They are solitary fish but in areas where food is particularly abundant they may gather in large numbers.
At night they emerge from their cavernous homes to hunt for food, using their extremely acute sense of smell to locate small fishes, particularly the rock-haunting blennies and gobies, and their preferred dish-octopus.
Locating prey by scent, morays have little difficulty in finding an angler’s bait. Young 15-30cm(6-12in)longmorays can be caught on the shore in rock pools while the larger eels live in deeper water, down to about 40m (130ft). There is very little information on the depth at which they are most abundant.
Morays are extremely aggressive and usually attempt to bite when handled. The teeth are very sharp and can inflict deep punctures which, if not treated early enough, can turn septic.
It is not only the moray’s bite that is venomous. Its flesh is believed to become toxic if it feeds on blue-green algae. If eaten by humans the poison can cause stomach cramps and nervous disorders.