This is a video of Atlantic salmon spawning in Spain.
From AFP news agency:
Atlantic Salmon returns to Seine
by Emmanuel Angleys – Tue Aug 11, 5:21 am ET
PARIS – After an absence of nearly a century, Atlantic salmon have returned to France’s Seine River, with hundreds swimming past the Eiffel Tower and Notre Dame cathedral this year alone, researchers told AFP.
The reappearance of salmon and other species chased from these waters by dams and pollution is all the more remarkable because no efforts have been made to reintroduce them.
They came back on their own.
“There are more and more fish swimming up the Seine,” said Bernard Breton, a top official at France’s National Federation for Fishing.
“This year the numbers have exceeded anything we could have imagined: I would not be surprised if we had passed the 1,000 mark,” he told AFP by phone.
2008 was already a record-breaking year, with at least 260 tallied on a video system in the fish passage of the Poses dam above Rouen, a city roughly half way between Paris and the Atlantic Ocean.
Historically, the Seine hosted a flourishing population of salmon, a migratory species that return from the sea to their freshwater birth place to reproduce.
But the construction of dams, and especially the fouling of the Seine with chemical runoff from industry and agriculture along with organic pollution, led to their local extinction sometime between WWI and WWII.
Today, Salmo salar, or Atlantic salmon, is listed as a threatened species throughout Europe.
Imagine the surprise, then, of the weekend angler who reeled a six-kilo (13-pound) specimen just downstream from Paris at the end of last month.
Or the dozing fisherman in Suresnes, also downstream from the city gates, who snagged an even bigger one last October, the first such catch in over seven decades.
Salmon are not the only fish in the Seine making a comeback.
Today there are at least 32, according to the water purification authority for the larger Paris region. The lamprey eel, sea trout and shad have all joined salmon in the Seine over the last few years.
The reason, say scientists, is simple: cleaner water.
In the mid-1990s, “between 300 and 500 tonnes of fish died in the Seine up river from Paris every year because of pollution,” said Breton.
But massive efforts over the last 15 years, including a new water purification plant, have removed much of the river’s pollutants.
The rivers of the South Wales coalfield once ran black with mining waste and were so polluted in places that no life could survive. But, in one of the most remarkable environmental turnarounds Britain has ever seen, a 20-year effort to clean them up has paid off – salmon have returned to all of them: here.
Freshwater Fish Populations See Rapid Decline: here.
The European eel’s migration to the Sargasso Sea to spawn is one of nature’s great unsolved mysteries. New research: here.
About salmon migration: here.