The eel is disappearing!
The mythical eel is born in the Sargasso Sea, off the coast of North America on the other side of the Atlantic. With the help of the Gulf Stream, it makes its way to our waters in northern Europe, while at the same time undergoing a remarkable transformation from larva to juvenile eel. But the eel’s journey is fraught with tough obstacles.
Arriving at the coastline of Northern Europe, a long swim up along various watercourses begins. Along the way, there are e.g., hydroelectric power plants – which are very difficult for the eel to get past alive. Those who still make it all the way to a lake or a quiet stream – then, many years later, need to take the same route back again to return to the Sargasso Sea and reproduce. Hydroelectric power plants become a death trap on their way back to the sea. Many eels get stuck in the large turbines where the water rushes through. Only a very small fraction of the eels makes it all the way back to the Sargasso Sea again.
Along the eel's path, there are numerous hydroelectric power plants, which become obstacles for the eel both upstream and downstream in watercourses.
Photo: Mattias-Ivermark-CC-BY-SA
An adult eel attempting to return to the Sargasso Sea to reproduce doesn't stand a chance against the hydroelectric turbines it encounters along the way. Many adult eels end their lives this way.
Photo: Ingemar Alenäs
Downstream from a hydroelectric power plant, a channel is sometimes left dry. This makes it difficult for both migrating fish and other species to survive in the watercourse.
Photo: PeterF-CC-BY
An obstruction for migrating fish can also be a poorly constructed culvert.
Migration obstacles in water and on land
Migration obstacles are a problem for many species, not just the eel. A migration obstacle can be anything that prevents an animal from getting from one place to another. Hydropower and other dams are problems for many more fish species than the eel. To help the fish, stairs, canals or other trails can be built that hopefully will guide the fish past the dangerous turbines. Other migration obstacles can be culverts, roads or bridges that were not built with the animals in mind. Amphibians that need to move from one body of water to another may have to cross a dangerous road to get there, and wildlife fencing along major roads can prevent larger animals from moving freely in a safe manner.
There are ways for young eels to bypass hydroelectric power plants on their journey from the sea to lakes. Here, American eel larvae climb a specialized ramp designed with good grip for these slippery fish.
Fish ladders are also ways to guide fish upstream past hydroelectric power plants.
Salmon jumping in a fish ladder.
Photo: John-Pavlish-CC-BY-SA
Sometimes, a so-called bypass channel is constructed, resembling a natural stream, directed around a hydroelectric power plant to increase the chances for fish to migrate.
Photo: Franzfoto-CC-BY-SA
Fish elevators, too, have been a method used to attempt to solve the issue of hydroelectric power as an obstruction to fish migration.
A tunnel constructed under a road, designed for both aquatic and terrestrial animals to pass safely.
Photo: Cephas-CC-BY-SA
Roads can be barriers to amphibian migration; here, a tunnel has been constructed to help amphibians cross to the other side of the road.
Photo: RuM-CC-BY-SA
A tunnel for hedgehogs, through a wall. Perhaps another way to eliminate migration barriers?
Photo: The-wub-CC-BY-SA
Wildlife crossings are bridges that wild animals can use to move from one side of an obstruction to the other.
Photo: Sillerkiil-CC-BY-SA
Bat bridges are designed to work with the echolocation of bats - so that bats fly high enough over roads or other obstacles.
Photo: MikeCalder-CC-BY
Squirrel bridges don't need to be more complicated than a sturdy rope between two trees - and can be used by squirrels and other small animals to cross roads and other barriers.
Photo: Sebaso-CC-BY-SA
Deer using a wildlife tunnel under a major road - a method to both reduce wildlife accidents and increase opportunities for animals to move past human barriers.
Photo: Oregon-Department-of-Transportation-CC-BY
Authorisation to fish for eel
In addition to migration obstacles, one of the biggest threats to eels is fishing. The International Council for the Exploration of the Sea (ICES) recommends that eel fishing should be completely stopped, but despite this, fishing continues both legally and illegally. Before Christmas 2013, a container containing 7 tonnes of live eel was discovered in Denmark. They were poached. This means that the fisherman did not have a permit to fish. The eel was to be sent to Japan.
However, only professional fishermen are allowed to catch eel. In addition, they are only allowed to catch a small number of eels for sale. In Sweden, there is a long tradition of eel fishing. Therefore, many Swedish politicians have fought for fishing to be allowed to continue – despite the scientists recommending that it should be stopped.
Despite the eel being critically endangered, it faces not only migration barriers and environmental destruction but also fishing pressures.
Photo: Tasja-CC-BY-SA
Electricity labeled with the 'Good Environmental Choice' allocates funds each year to help the eel and reduce the number of eels killed by hydroelectric power plants.
Photo: Ingemar Alenäs
What can I do?
Do not eat eels. Inform others that the eel is endangered.
Change your electricity company to one that chooses to supply electricity with the Swedish Society for Nature Conservation’s Good Environmental Choice label. Every year they earmark money to help e.g. the eel.
Get involved in the Swedish Society for Nature Conservation, the World Wide Fund for Nature (WWF) or another organisation that works to protect the eel.