The Environment Agency stocked 3000 rare crucian carp into a fishing lake near Lyng on Tuesday, 10th July. The fish were reared at the Environment Agency’s fish farm at Calverton and have been stocked into the lake to try to establish a population of the species, which will remain as true crucian carp.
Crucian carp have become increasingly rare because they interbreed with feral goldfish and common carp, which have been widely stocked in many lakes for angling. There are few waters left with pure strains of the species and they are thought to be almost extinct in Norfolk.
Adam Piper, an Environment Agency ecology expert said, “We chose the lake because it does not have any common carp or goldfish in it, so the pure-bred crucian carp population should be maintained. We hope this will establish a successful population in Norfolk that will become a source for stocking suitable waters elsewhere in the county.”
Crucian carp are a very hardy species of fish which can survive in temperatures almost to freezing and as high as 380C. They are tolerant of low dissolved oxygen levels and can live where many other fish species cannot. Pure-bred crucian carp are quite difficult to identify from hybrids, and any records of their presence need to be carefully checked.
Adam concluded, “We are very pleased that the Norfolk Anglers Conservation Association (NACA) wanted to help conserve this species and that once established, this will lead to further introductions in other suitable lakes.”