Giant shrimps in the Brenne ponds? The idea has been floating around in Alexis Boëly's head for three years. The fish farmer from Mézières-en-Brenne requested authorization to test the breeding of Macrobrachrium Rosenbergii, a freshwater shrimp native to Southeast Asia, more commonly called a “chevrette”.
“Shellfish have always interested me. Taste first, I love it. And on a professional level too. Until now, I mainly knew seawater shrimp thanks to my years spent in New Caledonia and then in Gravelines, near Dunkirk (North)”, says Alexis Boëly. Looking for diversification for his fish farming in Brenne, he heard about the “chevrette”, already raised in France in the Gers and recently in Ain. “I went there to see how they worked. Technically, it's not much different from fish farming. I also took the opportunity to taste it. It was a great discovery: it is a shrimp with firm flesh and a very subtle taste. »
Alexis Boëly then inquires about the standards required for his breeding. “The first condition is to have a completely closed aquaculture installation to avoid any risk of propagation of the species in the natural environment,” explains Charlotte Jacquet-Martin, head of the water-nature risk planning department, at the Departmental Directorate of Territories (DDT) of Indre. “This is precisely our case. THE seven small ponds dedicated to shrimps are in a closed circuit. They do not communicate with any watercourse and are fed by rainwater. They serve as winter storage space for the fish,” explains the fish farmer.
Seven small ponds, with a surface area of between 400 and 1,000 m2, will be dedicated to shrimp.
© (Photo NR, Martine Roy)
Its operation ticking all the boxes, the Departmental Directorate of Territories (DDT) gave the green light. A first prefectural decree “authorizing the experimentation of growing freshwater shrimp in closed ponds” was published on October 10, 2024. Too late to implement the project this year, the shrimp season being over. “Production extends from spring until the end of September, during the summer months. The doe needs temperatures between 18° and 26°C to grow. »
Objective: 300 kg of shrimp per year
The experiment is therefore postponed until spring 2025. This additional time will allow Alexis Boëly to carry out development work. “We are considering the construction of a building equipped with photovoltaic panels, where the nursery will be located. These are heated above-ground basins which will accommodate the larvae and juveniles, while waiting for the water in the on-ground basins to warm up naturally. We are also planning a shrimp slaughter room, equipped with cold rooms. » Alexis Boëly sets a production objective of around 300 kg of goats per year.
“When the season is over (end of September/beginning of October), the pools will be dried out. Their drain water will be stored in another 6,000 m basin2 then reused for the following season. There is therefore no release into the natural environment”, reassures Charlotte Jacquet-Martin who judges “this type of breeding is difficult to generalize in Brenne. Few operations can justify a truly closed system, as is the case at Alexis Boëly.”
To avoid any predation, the operator has also planned to equip his ponds with protective nets. “We are going to put some on the surface, to protect the shrimp from piscivorous birds (the heron, the diving duck, the grebe); but also along the banks in anticipation of coypu and muskrats. »
Should you be afraid of shrimp?
Are shrimp likely to become in the very long term the new bane of the Brenne, in the same way as the invasive Louisiana crayfish? “These are two very different files, distinguishes Charlotte Jacquet-Martin. In the case of shrimp, we are dealing with very regulated and controlled breeding. Louisiana crayfish are an invasive exotic species that appeared in the early 2000s and are unwanted. The order authorizing their marketing has the sole aim of trying to regulate the species. We are absolutely not in a production but in a sampling of individuals already present in the environment. » The fish farmer also wants to be reassuring. “Unlike crayfish, shrimp need water to move around. And as the pools are in a closed circuit, there is no risk that she will look elsewhere. And anyway, it's a warm water species. Below 12°C, it dies. »
