Anglerfish spawn in very deep water, laying their eggs in sheets that can form huge surface rafts up to 10m long. These have been mistaken for sea monsters. The sheet from one female can contain a million eggs. On hatching, young anglers remain in open water until they measure about 8cm. Extra-long fins help keep them afloat but recede once the angler settles on the seabed.

In gastronomic circles, an anglerfish is known as a monkfish. The flesh of its tail is sometimes used as a substitute for scampi. A better claim to fame is that the first insulin was extracted from its pancreas. Anglerfish can reach up to 2m in length. The huge flattened head is allied to a tail of more normal proportions.

Angler fish usually just rest on the seabed, lying in wait for their prey. They derive their name from the fishing rod formed by the foremost spiny ray of the dorsal fin. This rod can be moved around, and its fleshy tip acts as a lure, inviting inquisitive creatures perilously close to the vast upturned mouth.

For such large fish, anglers can be incredibly difficult to spot. Their coloration and shape help them blend with the seabed, and leaf-like flaps of skin round the head and body break up their outline. Divers have nothing to fear unless they accidentally rest their hand in an anglers mouth. It has been known!

Prey lured near the anglers mouth by the fishing rod are taken in with a gulping motion. The opening of the fishs jaws causes an inrush of water that makes evasion virtually impossible. Large, inward-curving teeth seal the fate of any foodstuff making a last-minute escape bid.

All sorts of fish are taken as prey, including bottom-living species such as flatfish, gurnards, dogfish, rays and even conger eels. Anglers have also been known to leave the seabed and attack sea birds on the surface. They are usually seen in water deeper than 15m.