Overwintering

We harvest all the first year ponds during January and February and the 0+ fish are over-wintered in 62 GRP tanks. The tanks are supplied with 80-100 litres/min of water and are capable of holding 20-25,000 '0+' 5cm fish. Calverton has the advantage of a reliable supply of borehole water, which has a fairly constant temperature of 9.5 to 10.5⁰C throughout the year. This is an ideal temperature for maintaining chub, dace, barbel etc over the winter period.

Between January and May (when they are stocked out for their second year), the fish will increase in fork length by approximately 15%. More importantly their condition will not deteriorate giving them a good start when stocked out at the beginning of their second summer.

Harvesting, fish handling and delivery

Due to the graded nature of the pond bottom, the fish are concentrated at the outlet monk when the water is lowered. From here they are hand netted and transported to the holding facilities using 400lt tanks mounted on steering trailers towed by small 4x4 tractors. Each trailer and pair of tanks has its own aeration system and is capable of transporting up to 5,000 1+ second year fish.

we put the fish into tanks, which have clean water flowing through them, and leave them undisturbed for at least 24 hours to remove any silt and mud which has clogged the gills, and to evacuate their guts of any ingested mud or food. The GRP holding tanks are supplied with 100-120 litres per minute of borehole water and are capable of holding up to 10,000 1+ second year fish.

We then sort the fish by species and an accurate fork length/weight sample taken. All fish are graded according to size using a mechanical grader and accurately counted via computerised fry counters. These greatly reduce handling stress and damage enabling the counting and grading of up to 40,000 fish/hour.

We normally deliver fish using a purpose built 6x6 Land Rover mounted with 300 litre tanks. Each tank has its own oxygen and air supply and on occasions, sometimes we may also use a large trailer. This provides the capacity to carry more than one order at a time and to introduce accurate numbers of fish at multiple stocking sites with the minimum of netting and handling.