Zerbst, Saxony-Anhalt, Germany. 18th Dec 2019. Steffen Zahn from the Institute for Inland Fisheries in Potsdam lifts a sea trout from an anaesthetic bath to weigh, measure and mark it. The animal had been caught during a trial fishery to prove that sea trout and salmon return to the Nuthe River at Zerbst. Credit: Mattis Kaminer/Alamy Live News
Mattis Kaminer / Alamy Stock Photo
Image ID: 2AGADMW