European conger (Conger conger) — spearfishing in Morocco

01 Telling it apart

A thick, scaleless, grey to dark brown eel with a pale belly, a long dorsal fin that starts just behind the pectorals and runs unbroken round the tail, and a large head with a wide mouth. The upper jaw is slightly longer than the lower, which separates it from the moray, whose jaws are equal and whose skin is patterned.

By day you see a head in a hole: a broad grey snout with a white-rimmed eye, often with the mouth slightly open and the gill opening pulsing. The body behind it is always longer than the head suggests.

At night it is out and moving, a long grey shape sliding along the base of the rock.

02 Habitat

Holes: cracks, stone fields, wrecks, the underside of boulders, harbour walls, anywhere rock offers a deep cavity with one entrance. A conger uses the same hole for months and years, and a good hole is rarely empty for long.

By day it stays in, with the head at the entrance or just inside. By night it hunts over open ground for fish, octopus and crustaceans.

It is on every rocky coast, from the harbour wall to deep offshore stone, and it is common.

03 Where to find it in Morocco

The whole coast, wherever rock offers deep cavities. Wrecks and harbour breakwaters hold big ones.

Its biology is well studied in Portugal and Ireland, not in Morocco. The age and maturity figures here are from the Portuguese work on the same Atlantic stock.

04 Spawning

Once, and then it dies. Mature congers leave the coast and migrate to deep water in the mid-Atlantic, where they spawn at depth and do not return. The eggs drift back as leaf-shaped larvae that take a year or more to reach the coast.

A large conger in a hole is therefore a fish that has not yet spawned, and one that will only ever spawn once.

05 Behaviour

Nocturnal. It spends the day in its hole and comes out at dusk. Since night diving is prohibited in Morocco, a conger is only ever taken in its hole, and that creates as many problems as it solves: a badly placed shot leaves the fish wedged in rock, alive, and impossible to remove.

It is not aggressive unprovoked, but it is strong, it twists without stopping, and it bites hard. A conger on a shaft is the most dangerous thing a spearo on this coast handles.

It does not spook easily by day; it simply withdraws into the hole if a diver crowds the entrance.

How you approach it

Locate the head and estimate the body. It is always longer than you think, and the shaft has to hold the head, not the neck.
A badly hit conger wedges in the rock and cannot be pulled out. A clean shot through the head, or no shot at all.
Thick gloves. The bite is dangerous and the animal thrashes without pause; a bare hand near the mouth is a mistake made once.
Never put a hand into a hole to check. Congers share holes with morays and both bite.
Bring it out with the shaft held firm and the head controlled, and dispatch it immediately. A live conger on a float line will find rock again.

What people get wrong

01 That a conger and a moray are the same kind of animal. The moray is patterned, with equal jaws and no pectoral fins; the conger is plain grey with pectorals.
02 That a big conger is an old fish that has bred many times. It breeds once, at the end of its life, and a big one in a hole has not yet gone.
03 That the danger is exaggerated. Congers have put divers in hospital. The bite is deep and the fish does not let go quickly.

Do not confuse it with

The species this one is taken for, and what tells them apart.

Mediterranean moray, Muraena helena — mottled brown and yellow, no pectoral fins, equal jaws, and a habit of holding the mouth open. Bites too.
European eel, Anguilla anguilla — much smaller, with the lower jaw longer than the upper and the dorsal starting well behind the head; a river fish met in estuaries.