A living fossil — a prehistoric giant that can grow to four metres, weigh over 300 kilograms, and live for a century — disappeared from Swedish rivers in the mid-20th century. Now it's coming back. Scientists are releasing thousands of Atlantic sturgeon juveniles into the Göta River, in one of the most ambitious fish rewilding projects ever attempted in Europe.
The Atlantic sturgeon (*Acipenser oxyrinchus*) once moved freely through European coastal waters and major rivers. These creatures have barely changed in 200 million years — they predate the dinosaurs. Their cartilaginous skeletons, rows of bony scutes, and elongated snouts are the same as they were in the Jurassic. But by the 20th century, overfishing, dam construction, and water degradation had wiped them out across most of their European range. In Swedish waters, they were gone by the mid-1900s. Gone for roughly eighty years.
**The Return of the Sturgeon**
The project, led by the Swedish Anglers Association (Sportfiskarna) in collaboration with the University of Gothenburg, the Swedish University of Agricultural Sciences, and the Gothenburg Museum of Natural History, is called exactly what it sounds like: 'The Return of the Sturgeon.'
The fish for the programme are sourced from a breeding programme in northern Germany, where a captive population of Atlantic sturgeon has been maintained to preserve the genetics of European lineages. Juvenile fish — 10 months old, roughly the size of a hand — are transported to Sweden and released into the Göta River, which flows from Lake Vänern to the North Sea through Gothenburg.
Releases began in 2024 with 100 fish. In 2025, a further 140 sturgeon and approximately 2,000 fry were released. The programme's long-term goal is to reach **5,000 to 10,000 juvenile releases per year**, building toward a genuinely self-sustaining wild population for the first time in living memory.
**A Living Fossil Reappears**
The Atlantic sturgeon is not just large — it is ancient in a way that makes the word feel inadequate. Adults can live 60 years or more. The species has a cartilaginous skeleton, no true scales (instead, bony plates called scutes run along its flanks), and a characteristically elongated snout used to probe the riverbed for food.
In the Göta River, researchers are tracking released fish with acoustic tags, monitoring their movement, habitat use, and survival. Early results are encouraging — fish have been detected moving downstream into coastal waters and returning, exhibiting the migratory instincts that define the species. One individual, detected by monitoring stations in the river, sparked what researchers described as genuine excitement in the lab.
**Why the Göta River?**
Historical records indicate that Atlantic sturgeon once spawned naturally in the Göta River. The river has undergone significant restoration work in recent decades — improved water quality, modified fish passages at some dams, reduced pollution from the paper and textile industries that once degraded it. Researchers believe it's now good enough to support a recovering population if given the right foundation.
The goal is not just to release fish and hope. The team is studying whether released fish will eventually spawn in the wild, producing a generation not reliant on captive breeding. **Wild-born Atlantic sturgeon in a Swedish river would be a true milestone** — something that hasn't happened in nearly a century.
**The Bigger Picture**
Atlantic sturgeon are critically endangered across their European range. The species was driven to extinction in most of its former habitat by a combination of commercial overfishing for caviar, migratory barriers, and river pollution. In the Rhine, the Elbe, the Thames, and dozens of other major European rivers, they are gone.
Sweden's project is part of a growing recognition that Europe's rivers can be rewilded — that even a species absent for generations can be coaxed back if the conditions are improved. Similar projects are underway in Germany and France.
For a fish that has survived asteroid impacts, ice ages, and the rise and fall of entire geological eras, the hope is that eighty years of absence from a Swedish river will, in the end, turn out to be a brief interruption. 🐟🇸🇪
*Sources: Swedish Anglers Association (Sportfiskarna) · Discover Wildlife · The Cooldown · Rewilding Europe · Daily Galaxy · University of Gothenburg*
