The salmon, which had disappeared from the Seine for almost 100 years because of dams and pollution of the river's waters, has just reappeared, accompanied by other migratory fish.
Salmon
The salmon is coming back and that is good news for the environment. It was again spotted in the Seine in 2008, where more than 250 specimens going up the waters of the river were observed by a video-counting system installed on a dam near Rouen.
Fishermen have also caught it: in Suresnes at the end of 2008, a fisherman had caught a 7-kilo salmon. In Pontoise recently, a 6 kilo specimen was taken.
No operation to reintroduce the species in Seine waters has been carried out. The salmon therefore came back on its own, proof of an improvement in the quality of the water and a reduction in pollutants in wastewater and industrial discharges into the river.
This fish, sensitive to the environment and the quality of the water in which it lives, is considered a reliable "bio-indicator" by scientists.
30 years ago, there were only 2 or 3 species of fish in the Seine according to the Interdepartmental Syndicate for Sanitation of the Paris Agglomeration (SIAPP). "52 species of fish are present today in the Seine basin, whereas the original fauna probably had many more" explains the Research Institute for Agriculture and Environmental Engineering (CEMAGREF).
With the salmon, it is the sea trout, the sea lamprey or the shad which returned. If the salmon were to breed in the Seine and its eggs were viable, we could speak of a real return. This does not appear to be the case at the moment, but observations continue.
vedura news source