The effects of the drought are becoming more and more visible.
Eleven tonnes of fish were found suffocated in a pond in Mably (Loire) due to drought, the Loire Fishing Federation said on Tuesday.
80 volunteers "removed 10.5 tonnes of dead animals on Monday and another 500 kg this (Tuesday) morning" from the Cornillon pond, located in the town of Mably, downstream from the Villerest dam (Loire), said Vincent Garnier, the development manager of the Loire Department Fishing Federation.
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According to the first scientific analyses, the lack of water due to the drought, combined with the development of algae led to the death of the fish.
The lowering of the level of the Loire, whose groundwater supplies the pond, has made the water stagnant.
"With the rise in its temperature which reduces its oxygen level, this constituted the perfect cocktail for the development of abundant aquatic vegetation", explained Vincent Garnier.
"The high consumption of oxygen by these algae during the night reduced its rate there in 15 days from 12 milligrams to 0.4 milligrams per liter of water", he continued, promising that a "state of specific locations of this pond" will be carried out by the fishing federation before initiating an action plan.
1% of animals saved
Nearly three-quarters of the asphyxiated animals were carp and the rest were predators such as zander, black bass, eels, as well as catfish brought back by the floods of the Loire and white fish, detailed this same source.
A rescue operation organized via social networks still saved one percent of them.
The volunteers went "to search with large landing nets for the tiny percentage of fish still alive in order to quickly release them into the Loire", explained Vincent Garnier, which made it possible to save a hundred kilos. -He specifies.
"In order to avoid a health disaster, we urgently decided not to wait for the arrival of a knacker but to dig a pit where the corpses were deposited and covered with quicklime, then with earth", explains the technician from the fishing federation who received the help of an excavator from the municipality of Mably and a backhoe loaned by a company to carry out the operation.
In mid-August, 100 tonnes of dead fish had been recovered from the waters of the Oder River, which crosses Poland and Germany.
Here too, the authorities suspected the proliferation of a toxic algae to be the cause of the carnage.
