Zander Sander lucioperca

The Zander, also called the Pikeperch, is native to deep lakes and slow-moving rivers and canals of western Eurasia, including fresh and brackish waters. It is not native to the UK but has been established as an invasive species since the mid 1800s. The images shown are juveniles - the adults can reach a metre long (typically half that), the largest of the perch family. Their size and elongated bodies can resemble Pikes, as do their predatory habits.