Atlantic sturgeon reintroduced to Sweden for the first time

Sturgeon Returns

€42,000 funding from Rewilding Europe European Wildlife Recovery Fund Supporting first reintroduction Atlantic sturgeon （Acipenser) in Sweden. “Sturgeon Returns“Initiative, by Swedish Anglers Association Sportfiskarna aims to repopulate the species in the Göta, Sweden’s largest river. A total of 100 young sturgeons were transferred from a farm in the village of Born auf dem Darß on the German Baltic coast and have now been released into the river near the Bohus Fortress in the municipality of Kungälv. The fish are 10 months old, 60 centimeters long and weigh about 1 kilogram.

“This is a unique and incredibly exciting event,” said project leader Linnéa Jägrud, who oversees the sturgeon return program Limnologist Works for the Swedish Anglers’ Association. “In Sweden, reintroductions of regionally extinct species are very rare. I look forward to the day when we can look at this river and say ‘here are Atlantic sturgeons spawning just below the surface’.”

Maximizing your chances of recovery

Until the beginning of the 20th century, there were spawning populations of Atlantic sturgeon in the Göta River. But then the species became locally extinct, mainly due to overfishing and deteriorating water quality. Until the beginning of the 20th century, there were spawning populations of Atlantic sturgeon in the Göta River. But then the species became locally extinct, mainly due to overfishing and deteriorating water quality. Historical specimens of Atlantic sturgeon collected from the Göta River in the collection of the Gothenburg Museum of Natural History show that the species once existed and spawned in the river. Three of the specimens were juveniles – juveniles cannot survive in salt water – which proves that the fish used to hatch in the river.

Today, the water quality of the Göta River has improved, and the river system is relatively biodiverse with a wide variety of habitats. Prior to reintroduction, suitable spawning habitats and food sources for Atlantic sturgeon were identified over a sufficiently large area. The reintroduced sturgeons are not expected to spend their entire lives in the river, but rather, as they grow older and larger and become more tolerant of salinity, migrate to the estuary and eventually to the sea. Juvenile sturgeons are initially kept in pools near the river to allow them to adapt to their new aquatic environment.

Important Eco Ambassador

The Atlantic sturgeon, also known as the Baltic sturgeon, is a species of sturgeon native to Europe and North America. It is a truly remarkable fish, with a lifespan of 90 years or more. It has been recorded growing to over 4 metres in length and weighing over 350 kg, although they are more commonly found between 1.8 and 2.4 metres in length. The Atlantic sturgeon does not have true scales, but instead has five rows of bony plates, called scutes, which range in colour from bluish black and olive green on the back to white on the belly. They mature sexually late (up to 15 years) and spawn less frequently (up to once every five years).

Sturgeon is the cornerstone, index species, play an important role in maintaining the health and balance of aquatic ecosystems. They use their narrow, cone-shaped heads to hunt for insect larvae and crustaceans, naturally disturbing stream beds, enhancing oxygenation, moving organic matter along waterways, and creating spawning grounds for smaller fish. They also serve as hosts for species such as lampreys and freshwater pearl mussels, and eat invasive species that would otherwise disrupt natural food webs. They rely on an interconnected network of habitats that provide them with suitable conditions for foraging, migration, and spawning, and are sensitive to changes in water temperature, oxygen levels, and other environmental factors.

“The sturgeon can become a symbol of the overall health of the Göta River,” Linnea Jagrud said. “It will become an ecological ambassador for the river.”

financial support

Sturgeon reintroduction efforts are ongoing with University of Gothenburg this Swedish University of Agricultural Sciences,as well as Gothenburg Museum of Natural HistoryAnd from Leibniz Institute for Freshwater Ecology and Inland Fisheries, Germany The institute is Europe’s leading authority on the ecology of Atlantic sturgeon and has been working on the reintroduction effort for many years.

The European Wildlife Return Fund grant covered a range of costs, including the relocation of the sturgeons from Germany and accommodation for the researchers and volunteers who tagged the sturgeons before their release.

“The reintroduction of the Atlantic sturgeon into Sweden after more than a century of absence is a huge milestone,” said Sophie Monsarrat, Rewilding Manager at Rewilding Europe. “I am delighted that the Fund has been able to support this release. Restoring the function of Europe’s terrestrial, freshwater and marine ecosystems by reintroducing the Atlantic sturgeon is urgently needed.” Key species”

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Like many other sturgeons, Atlantic sturgeons can tolerate a wide range of salinity and spend most of their lives in saltwater but travel upstream to spawn. Tagging and genetic studies have shown that sturgeons use the same breeding stream for many years and then return to the stream where they were born.

Before they were released into the Göta River, the young sturgeons were fitted with acoustic transmitters so they could European Tracking NetworkIn rivers and coastal areas outside estuaries, monitoring efforts will provide valuable insights into fish movements and behavior, enabling further enhancement of reintroduction efforts.

Going forward, our goal is to reintroduce more sturgeon into the Göta River each year.

“I would like to release at least a few thousand young fish, as the mortality rate is high,” explains Linnea Jagrud. “The ideal situation would be to set up a rearing facility in Sweden. This would increase the chances that the sturgeons will return here to breed. We want them to feel that Gotha is their home.”

The bigger picture

The Atlantic sturgeon’s main range is in eastern North America, from southern Canada to Florida. Here their numbers have declined significantly and they are now considered Vulnerable Globally. Scientists believe that a single population migrated across the Atlantic Ocean about 10,000 years ago and was historically distributed across northern Europe, including the Baltic region. However, due to overfishing, river channelization and damming, and pollution, the species became functionally extinct in Europe in the second half of the 20th century.

In Europe, Atlantic sturgeon are currently EU Habitats Directive and three other international agreements. Europe has been working on reintroducing Atlantic sturgeon since 1996, using donated stocks from the United States due to genetic similarities. The Oder River is the last major river in Germany and Poland where sturgeon and other animals can migrate long distances unhindered, and has been a focus area for reintroduction of the species since 2006, following the transfer of stocks from Canada’s St. John’s River. Release 600 sturgeons in the river near the town of Krivén. Other reintroduction programs have been implemented in the Vistula River (Poland), the Neman River (Lithuania), the Pärnu River (Estonia), and the Narva River (Estonia).

Let’s return to the wild

The flexible setting of the European Wildlife Return Fund aims to support wildlife return in a convenient and flexible way. Rewilding Europe invites other initiatives working to reintroduce key species in European landscapes Consider applying Get a grant.

“The grant we received was easy to get and very helpful,” says Linnéa Jägrud. “It has been a pleasure working with Rewilding Europe. I would like to see the Göta River and the adjacent coastal areas become part of a larger marine rewilding landscape.”

Those interested in contributing to wildlife recovery in Europe can Support the return of wildlife by making an online donationIf you wish to invest more than €50,000 in the European Wildlife Return Fund, We would love to contact you personally.

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