Tench

Resilient fish

Also called the doctor fish, the tench is a very resilient fish and can survive far lower oxygen levels than many other fish. Due to this robustness it is suitable for fish farming.

In the winter tench stop eating and their body temperature falls to match that of the surrounding water. They enter a hibernation-like state and dig themselves into the sand or mud.

Tench are crepuscular, which means they are active in the evening and at night, which is when they hunt for food on the lake or riverbed and around plants. 

Planted as food fish

Previously the tench was a popular food fish and was actively introduced to many bodies of water. Today it has been planted out in all continents except Antarctica.