700 Russian sturgeons were released on Friday in the Danube, one week before the World Fish Migration Day, celebrated globally on October 24th . This is the second restocking event organized in Isaccea in 2020 by the “Danube Delta” National Institute for Research and Development (DDNI), WWF partner in the MEASURES project.
The Russian sturgeon (Acipenser gueldenstaedtii), a native sturgeon species from the Danube, can reach 2.35 m in length and weigh over 100 kg. But the sturgeons released now barely exceed 25 cm and 150g, otherwise a normal size for 6 month-old sturgeons. They will most likely not stay in the Danube, but will migrate to the sea in a few days, where the water temperature fluctuations are not so great and where there is more food for them than in the river. All sturgeons are marked so that they can be identified in the event of an accidental capture or during scientific research.
"Each sturgeon has an external mark with the name of the project and the telephone number where the accidental capture of a sturgeon can be reported. But fishermen in the area already know about our restocking actions and usually release them in case they accidentally catch them. Especially since some of the fishermen also know that the Russian sturgeon is the most vulnerable sturgeon species " - Marian Paraschiv, DDNI Tulcea.
Also known as the diamond sturgeon or Danube sturgeon, the Russian sturgeon is increasingly rare in Danube waters, being on the IUCN Red List of critically endangered species. Like for most migratory fish, population decline is caused by the growth of the hydropower sector, overfishing, climate change and pollution, all of which are human-based ctivities. As a result, not only sturgeons, but most populations of migratory freshwater fish species have declined, on average, by 93% in Europe since 1970.
"Rivers that flow freely and migratory fish, such as sturgeon, trout, Danube shad, are extremely important for local communities – being in the past a source of food - but also for those who live beyond the river. Because these fish play an essential role in the health of rivers, lakes and wetlands by maintaining a complex food chain. That is why, in the MEASURES project, we chose to mark the World Fish Migration Day through a restocking activity among others ”, added Cristina Munteanu, Project Manager, WWF-Romania.
Another 300 year-old Russian sturgeons were released at Isaccea in April, and 1000 last year. This is the third restocking action organized within the MEASURES project in Romania, bringing the total number of sturgeons released in the Danube, in both Romania and Hungary, to almost 9000.
The release activity took place in the presence of representatives of the DDBRA (Danube Delta Biosphere Reserve) and NAFA (National Agency for Fisheries and Aquaculture), as administrators of aquatic resources, and of the representatives of DDNI, as organizers of the action. The event in Isaccea was organized within the MEASURES project, a project co-financed by the European Union (ERDF, IAP).
 Managing and Restoring Aquatic Ecological Corridors for Migratory Fish Species in the Danube River Basin
 The Living Planet Index (LPI) for Migratory Freshwater Fish