By Caroline Wyatt
BBC News, La Rochelle, France
Baby eels are now more expensive than caviar in France, and even rarer - disappearing off the menu thanks to huge demand in Asia.
The eels - known as "glass eels" because they are transparent for the first years of their life - used to be a delicacy in France, but these days they are so expensive they are known as "white gold".
Glass eels are the young of the common eel
Sold by French fishermen to China and Japan, glass eels are grown for several months before appearing on the menu as an aphrodisiac speciality.
Prices are now so high in France that the eels are disappearing from many of Europe's rivers, and some in France are now calling on the European Union to take drastic action and stop eel fishing altogether to prevent extinction.
Off the menu
The popular La Cagouille restaurant serves all the best regional specialities to the people of La Rochelle - French snails dripping in garlic butter and every kind of fish.
The chef, Karim Sherif, would love to offer his customers glass eel - known here as pibales - long a local delicacy. But these days, glass eels are off the menu.
"The problem is that we just can't buy them, or rather we can't afford to sell them because the eels are just too expensive," Mr Sherif says.
"It's something like 700 euros (£480) a kilo, so when people hear that they just don't order them any more."
Inside the main market at La Rochelle, there are dozens of fish stalls - selling incredibly fresh fish and everything from salmon and skate and cod to fresh oysters and lobsters, but there is not a single baby eel in sight.
I have found one stall that sells fresh eels, but these are Mediterranean eels and they are raised in fresh water. But Marie Claire, who runs the stall, does not have any glass eels, although she remembers eating them when she was young.
"Well you can buy them but it costs an arm and a leg," she says. "They're so expensive they're like gold - 600, 700, 800 euros a kilo. I tasted them once when I was very young - they were delicious. But it was years ago.
"A very special taste, cooked with parsley and garlic, but I haven't had them for 40 years or so."
To find the eel fishermen themselves, I was told to go 20km (12.5 miles) up the coast to the tiny port of Charron to meet Bruno Monroe, vice-president of the local fishing committee, who had just been out looking for glass eels.
He arrived with a bucket of glass eels - not even a full bucket. The glass eels, an inch or two long, were wriggling around at the bottom, almost totally transparent apart from a fine black line down their backs and two tiny dots for eyes.
"Three hours of work and all I got was this," he said. "It's the end of the season and there are far fewer eels around now."
The headlines have mostly been negative, with a war of words as to who is to blame for the scarcity of glass eels.
There is no doubt that stocks in France and elsewhere in Europe are in steep decline - but why?
Some say it is the fishermen's fault - for overfishing. Others blame poachers, attracted by the large sums of easy cash to be earned.
But amateur eel fisherman Michel Lajonc says the poachers are not the real issue.
"That's not the problem - we have to absolutely forbid the sale of eels to protect the species," he said.
"We must do it right away because soon it will be too late. The professional fishermen are exhausting the stock. And the problem in France - like most of the western world - is that we're all obsessed with immediate profits, we just don't think about future generations at all."
But eel expert Eric Feunteun at the University of La Rochelle disagrees. He is fascinated by the glass eels' long and mysterious journey all the way from the Sargasso Sea to the shores and rivers of Europe - where so many baby eels die before they can spawn their own young.
"There are lots and lots of other causes - for example, reduction of habitat, diminution of the quality of the water and ... the importance of the dams which stop the eels from migrating upstream but also kill them when they go back downstream," he says.
So what can be done to save Europe's eels? The EU has discussed banning eel fishing altogether. But Eric Feunteun says that would be unwise.
"Fishermen are very important for the river systems because they are the only people who live there all the time and who can give you information on the state of the river and stocks," he says.
"If they go away, and they will go away if we close the fisheries, we will have no information at all. So they really play a crucial social role."
The only other option is to persuade China and Japan to find a way to breed their own eels to cater for the growing demand at restaurants across Asia - something scientists there are trying to do.
But they will have to be quick - otherwise, like the sturgeon and its caviar, the eel could prove the victim of its own success.