This 2-metre monster latched onto a diver's face with its needle-sharp teeth and left him needing more than 20 stitches and plastic surgery…

In the summer of 2013, a group of divers were exploring the coastline of Western Ireland, just off Connemara in County Galway. Among them was Jimmy Griffin, a baker with a couple of decades of diving experience who was enjoying his first scuba expedition in 2 years.

The group had paused to watch a couple of lobsters when Griffin was suddenly grabbed by a 2-metre-long eel that latched onto his face. The attack was brief, but left Griffin requiring more than 20 stitches and plastic surgery, and in no doubt of the power of a conger eel.

Congers lurk in reefs and shipwrecks through much of the north-eastern Atlantic Ocean and Mediterranean Sea, where they tuck into holes and crevices, slipping out, normally at night, only to scavenge and hunt.

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They are the heaviest species of eel in the world, weighing as much as 120kg and reaching 3 metres in length, with even larger specimens reportedly caught in trawler nets. 

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The battleship grey body is scaleless, with a singular fin running along the back and much of the belly. Congers have large heads, with dark, rounded eyes and powerful jaws, the mouth lined with needle-sharp teeth.

They are unfussy eaters, and will spin, rather like a crocodile, to try and take chunks of flesh from the corpse of a shark or cetacean, something Jimmy Griffin was unfortunate to experience.

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There is uncertainty surrounding the breeding process of the European conger. They are believed to migrate to the mid-eastern Atlantic Ocean, possibly near the Azores or further west in the Sargasso Sea, but there may also be spawning grounds within the Mediterranean.

The larvae disperse on ocean currents while the adult fish, having not eaten since they began their breeding journey, then die. 

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