With all the problems stocking brown trout in rivers and their effects on the wild fish population, we were fortunate enough to be given the opportunity to try an "In-stream Hatchery". The trout reared in this fashion will have all the instincts of a wild fish, but given an important helping hand during their most vulnerable stage, plus 20,000 eggs are considerably cheaper than 200 twelve inch fish. This project was partly funded by the Environment Agency who had the equipment built by Vaughan Lewis. He used plans from the USA, here they tend to use an old freezer as the container, luckily ours was a modified olive green water tank.

The hatchery was installed in the small spring below Larkham's Leat (Whitfield Hatches), blocking the hatch with a few scaffold planks gave enough head of water to place the filter. Water then travels through the filter, down the pipe and enters the tank in the base. Inside it is forced through a "Jacuzzi" type contraption and percolates through the gravel, before escaping out of two pipes.

Female eyed eggs were purchased from same supplier as our stock fish and placed in layers between the gravel. The lid was securely attached and covered with a disguising layer of water cress.

After the eggs hatch, the egg sac fry (alevin) normally distribute themselves throughout the gravel where they absorb most or all of their egg sacs. Three weeks later, the lid was carefully removed and a we spotted a few empty egg shells. With closer inspection, we finally spotted an alevin, about 1cm long -- success.

They then absorbed their egg sacs, make their way up through the channels in the coarse gravels to the top. These "swimup" fry, dart immediately to the waters surface to gulp air to inflate their swim bladder. Attracted by the light from the outlet pipes they swim towards freedom. The fry are now free, efficient swimmers and begin to feed, thus completing the first process of their life cycle.

Has it all been a worth while – we will find out when we "electro" fish the Upper Water in the Autumn and should encounter these little fish, now about 6-8 inches long.

John Grindle