>Jérôme Gurruchaga runs an eel farming family business in southwestern France. The glass eels he buys from local fishermen mature into yellow and then silver eels, a delicacy with high market demand.
>
>Jérôme’s facility uses the latest technologies to grow five million eels. They also use a closed circuit where they recycle the water. He says that the advantage of this is that they then don’t have to use any antibiotics or pesticides.
I am all for aquaculture, especially in a case like eels, where the population has collapsed and there is high global commercial demand. Besides, Japanese unagi dishes with whatever that sauce is that goes on the eel are goddamn delicious.
Not only that, but the crash in eel populations in Europe — due to demand from East Asia — has spread over to North America as Asia started buying eels from North America after Europe was depleted. So it’s a problem afflicting the US as well.
However, my understanding from past articles is that the bottleneck with eels is one of a lack of *young* eels. There is already a ton of aquaculture of eels in China. What’s being caught and transported is young eels, which are then grown in China. We know how to farm eels from the young to adult stages.
What we don’t know how to do is get eels to breed in captivity — they have a fancy spawning cycle that involves a bunch of migration. So we can’t do domestic production of more young eels yet. So aquaculture isn’t a complete answer yet.
>How are baby eels made? We still don’t know
>
>Eels exist, of that there is no doubt. Yet these slippery customers have never been spotted mating or giving birth in the Sargasso Sea or anywhere else
>
>Aristotle thought they came from earthworms. Others thought they spontaneously generated. And to this day, no one really knows precisely where eels are made.
>
>Yet there are eels – lots of them.
>
>Over the past century, a consensus has formed that American and European eels journey thousands of kilometres across the ocean to spawn in the conducive conditions of the Sargasso sea. In this vast, self-contained gyre of water in the western Atlantic, near Bermuda, the water is warmer and saltier than the surroundings. The newly spawned elvers then make their way home.
>
>But this extraordinary mission is a matter entirely of inference, first drawn by Danish researcher Johannes Schmidt after a series of expeditions to the Sargasso a century ago. No adult eels have ever been caught spawning there. Until recently, none had even been seen en route. “Their migration remains a complete mystery,” says Melanie Beguer-Pon of Laval University in Quebec. Yet there must be something to the Sargasso tale, says Håkan Wickström of the Institute of Freshwater Research in Drottningholm, Sweden. “They must spawn there because the tiniest eel larvae are found there,” he says.
>
>And so the story goes: on the brink of sexual maturity, eels leave the shores of Europe or North America for the depths of the Sargasso sea, where they engage in panmixia, a wriggling orgy of individuals randomly mating with each other. The resulting larvae mature into transparent “glass” eels as they make the return journey to spend their lives in river estuaries on their respective continents.
If we could figure out how to artificially get eels to kick off that panmixia business, then we could beat the eel shortage issue and do a lot to reduce the impact on the wild ones from overharvesting.
1 comment
>Jérôme Gurruchaga runs an eel farming family business in southwestern France. The glass eels he buys from local fishermen mature into yellow and then silver eels, a delicacy with high market demand.
>
>Jérôme’s facility uses the latest technologies to grow five million eels. They also use a closed circuit where they recycle the water. He says that the advantage of this is that they then don’t have to use any antibiotics or pesticides.
I am all for aquaculture, especially in a case like eels, where the population has collapsed and there is high global commercial demand. Besides, Japanese unagi dishes with whatever that sauce is that goes on the eel are goddamn delicious.
Not only that, but the crash in eel populations in Europe — due to demand from East Asia — has spread over to North America as Asia started buying eels from North America after Europe was depleted. So it’s a problem afflicting the US as well.
However, my understanding from past articles is that the bottleneck with eels is one of a lack of *young* eels. There is already a ton of aquaculture of eels in China. What’s being caught and transported is young eels, which are then grown in China. We know how to farm eels from the young to adult stages.
What we don’t know how to do is get eels to breed in captivity — they have a fancy spawning cycle that involves a bunch of migration. So we can’t do domestic production of more young eels yet. So aquaculture isn’t a complete answer yet.
https://www.newscientist.com/article/2081008-how-are-baby-eels-made-we-still-dont-know/
>How are baby eels made? We still don’t know
>
>Eels exist, of that there is no doubt. Yet these slippery customers have never been spotted mating or giving birth in the Sargasso Sea or anywhere else
>
>Aristotle thought they came from earthworms. Others thought they spontaneously generated. And to this day, no one really knows precisely where eels are made.
>
>Yet there are eels – lots of them.
>
>Over the past century, a consensus has formed that American and European eels journey thousands of kilometres across the ocean to spawn in the conducive conditions of the Sargasso sea. In this vast, self-contained gyre of water in the western Atlantic, near Bermuda, the water is warmer and saltier than the surroundings. The newly spawned elvers then make their way home.
>
>But this extraordinary mission is a matter entirely of inference, first drawn by Danish researcher Johannes Schmidt after a series of expeditions to the Sargasso a century ago. No adult eels have ever been caught spawning there. Until recently, none had even been seen en route. “Their migration remains a complete mystery,” says Melanie Beguer-Pon of Laval University in Quebec. Yet there must be something to the Sargasso tale, says Håkan Wickström of the Institute of Freshwater Research in Drottningholm, Sweden. “They must spawn there because the tiniest eel larvae are found there,” he says.
>
>And so the story goes: on the brink of sexual maturity, eels leave the shores of Europe or North America for the depths of the Sargasso sea, where they engage in panmixia, a wriggling orgy of individuals randomly mating with each other. The resulting larvae mature into transparent “glass” eels as they make the return journey to spend their lives in river estuaries on their respective continents.
If we could figure out how to artificially get eels to kick off that panmixia business, then we could beat the eel shortage issue and do a lot to reduce the impact on the wild ones from overharvesting.