“I’m a fish trapped by a dam. Will you give me a lift?” How car transport helps save eels in Czechia
The decline in eel populations is a long-term problem not only in Czechia but across the entire EU. The main cause is dams, which prevent their free movement. At present, their return to original habitats is mainly supported by transporting them from the sea into freshwater rivers, but it is becoming clear that much more will need to be done in the future.
Even though dams definitely carry some positive aspects, like providing flood control, serving as water reservoirs, and being a source of renewable energy, they can also be detrimental to the environment. In addition to the destruction of original ecosystems and often even human settlements, which literally become sunk costs, dams also create a barrier blocking fish migration. In Czech lands alone, there are hundreds of dams, mostly built in the 1950s and 1960s, with some of them being large enough to cover a medium-sized town. These gargantuan water constructions thus become an impassable obstacle for millions of fish that need to migrate in order to survive. One of the most impacted fish species are eels. Normally, they would spawn in the sea and mature in rivers. Nevertheless, if this is not an option, they need to be transported from one place to another by car.
“Eels spawn in the Sargasso Sea and then, as monté, they travel towards the coast of Europe. A monté is a young eel up to two years of age. Before it leaves seawater, it is caught and transported to farms, where it is fattened. We loaded it in Germany and brought it here to Czechia,” explains Petr Votípka from Klatovského rybářství, a company specializing in fish farming.
This year in the Plzeň Region, anglers released tens of thousands of juvenile European eels into rivers, in order to improve the population of this predatory fish in its natural habitat.
“We imported 500 kilograms of eels for stocking the fishing grounds of the West Bohemian Regional Association of the Czech Anglers Union. That works out at roughly 120 eels per kilogram, and they are about two to two and a half years old.”
The European eel was classified by the International Union for Conservation of Nature in 2008 on the Red List of Threatened Species as critically endangered. The major cause of the significant decline in its population is generally considered to be the construction of dams and hydroelectric power plants.
According to technician Jaromír Lev from the Plzeň 1 local organization, eels are therefore present in Czech waters only thanks to stocking.
“Right after being released, they usually hide in the roots to protect themselves from predators. These are mainly otters, perch, pike, zander, or catfish,” he says.
However, this is not the only danger awaiting eels.
“They will grow until adulthood and then head back to the sea, where they are supposed to spawn. But river connectivity is poor, so many of them end up in hydroelectric power plant turbines,” explains Votípka.
This year, the West Bohemian Regional Association will release juvenile eels worth a total of 2.5 million crowns. Of this amount, 2 million crowns will be covered by an EU subsidy, since improving eel populations in member states has long been an EU priority. In the Czech context, possible future solutions could also include the construction of functional fish passes and barriers that would prevent adult fish from entering hydroelectric power plant turbines.
