Zerbst, Saxony-Anhalt, Germany. 18th Dec 2019. Steffen Zahn from the Institute for Inland Fisheries in Potsdam (Institur für Binnenfischerei) drips an anaesthetic into a plastic tub. Salmon and sea trout are briefly anaesthetised in the liquid to measure, weigh and mark them. Zahn heads the migratory fish programme in Saxony-Anhalt. A total of 143,500 young salmon and 90,300 sea trout hatchlings have been released into the Nuthe near Zerbst over the past ten years. Credit: Mattis Kaminer/Alamy Live News

Zerbst, Saxony-Anhalt, Germany. 18th Dec 2019. Steffen Zahn from the Institute for Inland Fisheries in Potsdam (Institur für Binnenfischerei) drips an anaesthetic into a plastic tub. Salmon and sea trout are briefly anaesthetised in the liquid to measure, weigh and mark them. Zahn heads the migratory fish programme in Saxony-Anhalt. A total of 143,500 young salmon and 90,300 sea trout hatchlings have been released into the Nuthe near Zerbst over the past ten years. Credit: Mattis Kaminer/Alamy Live News

Mattis Kaminer / Alamy Stock Photo

Image ID: 2AGADMJ

Germany, Saxony-Anhalt, Zerbst, Steffen Zahn from the Institute for Inland Fisheries in Potsdam (Institur für Binnenfischerei) drips an anaesthetic into a plastic tub. Salmon and sea trout are briefly anaesthetised in the liquid to measure, weigh and mark them. Zahn heads the migratory fish programme in Saxony-Anhalt. A total of 143,500 young salmon and 90,300 sea trout hatchlings have been released into the Nuthe near Zerbst over the past ten years. The fish migrate across the North Sea into the Atlantic and return from there to spawn in the Nuthe after a few years. 2019 is the International Year of Salmon.