Calverton Fish Farm came into operation in the 1930s. It was built by the Trent River Board to produce brown and rainbow trout.
Today it concentrates on producing coarse fish such as chub (pictured here), dace and barbel. Half a million fish are produced every year. Coarse fish are those caught by anglers and then returned to the water.
Alan Henshaw is team leader at the farm. He has spent 25 years there. He said: "The farm is dedicated to one thing only - to produce fish for stocking rivers, canals and lakes the length and breadth of England and Wales."
The farm has a specialist hatchery where fish can be brought on. Eggs are stripped from adult fish in one part of the building and then passed to another via a hatch and laid in special trays.
The hatchery is the most important part of the farm. It enables the production of all the larvae needed for stocking the farm. Without the larvae there would be no fish to produce.
In a series of greenhouses you will find the first year fish. The greenhouses enable the water to warm up prompting quicker growth.
There are six ponds within the greenhouse, each with its own automated feeding system. Each pond can contain up to 30,000 young fish. The greenhouses were installed in summer 2009.
The fish spend their first summer undercover. They are somewhat mollycoddled and will even be given extra food rations if necessary. In their second year, life gets harder.
By year two the fish are outdoors. There are two outdoor sections on the farm - this is close to the greenhouses, the other is across the road. In each pond are 60,000 fish of half a dozen different species.
These are the ponds across the road from the farm. Automatic feeders provide food at specific points of the day. The fish have to fight for the food which toughens them up for when they are released into the wild.
Sheep play an important role. They eat the grass so the workers can concentrate on the fish. Once the fish are released they could enjoy a long life. Barbel can live for more than 20 years. Dace live around 10 years.
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