It is hard to mistake this deepwater fish for anything else but a gulper eel.
Its enormous mouth and small body instantly distinguish it from all other fishes.
Many body features that are characteristic of other fishes are much reduced in
this gulper, with teeth, eyes, and pectoral fins nearly nonexistent. Its overall
body colour is black with a white groove on each side of the dorsal fin, which
originates on the head and continues down the entire length of the body. This
species rarely exceeds 100 cm in length, much of which is tail. Males possess
elaborate, large olfactory organs, which are a good indication that mate location
in this species involves the release of pheromones by the female. Once a male
detects a female's scent he can follow the 'perfume' to its source.
The body of a pelican gulper is not built for chasing prey. Instead this fish
is an ambush hunter, possessing a unique set of strategies to lure and capture
its food. To attract squid, plankton and fish, the gulper waves the luminescent
organ at the tip of its tail in front of its mouth, or chases it round and round
in a circle. This odd behaviour is undertaken because not only must the prey be
lured within close range by the movement of the light, but the gulper must also
have its mouth in close proximity to the lure at all times. Once the prey is very
close, this fish lunges, opening its mouth at the last second. Water rushes into
the mouth, ballooning out the pelican-like pouch. Once the prey is swept into
the mouth with the current, the jaws snap shut. The water escapes, albeit slowly,
through the tiny gill openings, allowing the food to be swallowed. Gulpers are
themselves preyed upon by lancetfish and other large deepwater predators.
Pelican gulpers occur in all oceans, but in Arctic Canada, they are only found
in Davis Strait, where they are quite common. Individuals have been caught most
commonly at depths ranging from 711 to 2682 m, but they descend as far as 7625
m below the surface!