The final journey

The life cycle of the European eel involves one of nature's most remarkable migration stories. Yet they are now critically endangered – and no one knows why. Kevin Parr delves deeper -

- Kevin Parr

Peek over the parapet of a bridge just as daylight bleeds into dusk, gazing down through the clear layers of a shallow river or chalk stream, and you may glimpse the shadowy, serpentine form of an eel as it stirs for the night.

Darkness is when eels search for food, scavenging or hunting by way of an acute sense of smell. They nudge stones and nose into crevices, seeking invertebrates or small fish. Theirs is an unfussy, carnivorous diet, with individual preference sometimes dictating the shape of their mouth and head. Each year, however, fewer and fewer eels worm between the watery weed-beds.

Once common, the European eel (Anguilla anguilla) is in huge decline. Rated as critically endangered by the International Union for Conservation of Nature (IUCN), their estimated population has dropped by as much as 95%, and no one can be sure why.

Despite its appearance, the European eel is a fish, one of around 1,000 eel species worldwide. The dorsal, anal and caudal fins combine to form a singular, ribbon-like fin along much of its back and belly. This can be inconspicuous as the eel slithers through stone and weed, which, alongside a fixed stare and slippery form, adds to the impression of an aquatic snake. Their mysterious existence has long caused confusion, although their edibility has never been in dispute.

EAST END DELICACY

In his 1653 book The Compleat Angler, Izaak Walton recommended the eel be stuffed with herbs, anchovy and nutmeg before roasting on a spit. He also wrote of the Romans' fondness for the eel, noting that they “esteemed her the Helena of their feasts”, although he gives heed that physicians deem eel to be “dangerous meat” - reference, no doubt, to the toxicity of their blood.