By Peter Frost in Britain:
The riddle of the disappearing eel
Friday 25th April 2014
Floods on the Somerset levels, so disastrous to those who live and farm there, have had one tiny silver lining.
Eels, so threatened in recent years, found the bursting rivers and drains and vast flooded acres much to their liking and local companies like Brown and Forrest which specialise in smoked eels, as well as local anglers, have reported much improved eel catches.
Now there is even better news for the long-time survival of the European eels (Anguilla anguilla).
The young eels — known as glass eels or elvers — which arrive in the estuaries of our rivers at this time of year are back in ever-increasing numbers. Elver counts were good last spring but this year numbers have been estimated to have increased more than tenfold.
However, the newly installed barriers and pumps and the recently started dredging operations could have proved a real obstacle to the baby eels migration upstream.
That is why conservationists, eel enthusiasts and local elver fishermen have got together to move millions of young eels upstream in an attempt to give them a better chance of survival.
On the rivers Parrett and Tone in Somerset and the Severn in Gloucestershire the elvers need help where the waterways are blocked by man-made obstacles. Without being helped most would die.
Environment Agency-authorised fishing parties have been collecting the critically-endangered fish as part of a Sustainable Eel Group (SEG) project.
They caught more than 1.2 million in the River Parrett on the last night of March on the spring tide.
Andrew Kerr from the SEG told us the results had exceeded all expectations.
“It’s higher than we dared hope and is a really fantastic achievement,” he said.
“What we are doing in this phase of our restocking programme is to move them over the barriers within their river system.
“We know that most — some 90 per cent — of the glass eels die if they are the wrong side of the barrier.”
This news, good though it is, doesn’t change the overall picture. There is still a massive long-term decline in eel numbers right across other British rivers and all across Europe and the eel is still officially classified critically endangered.
No-one knows why eels are disappearing. With food tastes changing eels have become less popular so it’s unlikely to be overfishing. Climate change must be high on the list of likely causes.
So what do we know about the mystery of the disappearing eel? Actually we don’t really know much about the eel at all.
Take their amazing lifestyle. Most scientists believe that European eels originate from the seaweed forests of the Sargasso Sea far across the Atlantic Ocean.
After a long life in European waters, 20-year-old adults swim across the Atlantic to spawn and then die. The tiny worm-like glass eels hatch and then spend up to three years drifting back across the ocean to arrive back at the very same waters their parents once inhabited.
On that epic journey to the rivers and waters of their birth they turn into small worm-like elvers. For 20 years they live in these waters, growing longer and fatter and changing colour from gold to silver.
Europeans eat eels in huge quantities. The Japanese import them for the vast sushi market. In Britain we eat a few — very expensive elvers in season, some smoked eels and a reducing number of Londoners still appreciate jellied eels or eel pie and mash in a few specialty eateries.
But the eel remains a mystery. Amazingly, in this age where wildlife cameras and film teams seem to have captured many of the secrets of nature, they have not captured the mating and spawning of the eel.
Let’s welcome the return of all those elvers back to the still flooded Somerset levels for what it is — a tiny chink of sunshine in this beleaguered corner of the English countryside that has suffered so much in recent years from both natural disasters as well as Con-Dem government indifference.