Whilst recently sorting through the effects of my late mother I came across an envelope and its contents addressed to me in 1967 from Government Buildings, Mile Cross Lane, Norwich. The letter concerned my agricultural apprenticeship scheme at Burlingham Horticultural College, but what took my eye was a red cachet on the otherwise dull brown envelope. The cachet read “KEEP A SHARP LOOK- OUT FOR COYPU.” The threat was evidently real enough then for the government to have a warning cachet applied to its mail. What was the background to this warning ?
The coypu (Myocastor coypus) is a native of South America and has been widely farmed for its fur. It was originally introduced into Britain in 1929 for fur farming, but this was unsuccessful and ceased by 1945. These farms were often little more than poorly fenced off ponds etc. and escapes were commonplace. The escaped coypus became established in two centres in the British countryside. The first near Slough disappeared without official control by 1956. A second group seemingly originated from three farms near Norwich expanded to cover the whole of East Anglia.
Coypus quickly became a pest, devouring large areas of reed swamp, and targeting native plants such as Great Water Dock and Cowbane. They also damaged a wide variety of commercial crops including cereals, brassicas, sugar beet and other root crops. The most important damage in economic terms was caused by burrowing. They dug into the banks of rivers and ditches and disrupted drainage systems, with the attendant threat of flooding. Thus from the late 1950's an official control campaign began.
During the 1960's I was living at Church Farm in Bunwell well away from the Norfolk Broads. But the coypu had by then spread that far from their Broadland base and damage was noted in the sugar beet crops next to farm ponds. Careful observation soon found them burrowing and breeding in the ponds and rivers of the area, particularly on Tollgate Farm and beside the River Tas in Bunwell Fen. A system of trapping and shooting was implemented, presumably with government aid, and I still recall many being eliminated. Some weighed up to 32 pounds in weight, a large size for an aquatic rat.
The least palatable memory for a teenager was the wire traps containing a captured coypu being put back into the pond to drown the occupants. The expense of a shotgun cartridge seemingly too much for a swift death. I actually achieved minor fame in the Eastern Daily Press of March 24th 1961 under the heading GOOD SHOOTING, PETER. “ A Diss Grammar School boy, out with his father on Saturday, shot two coypu with one shot. Not content with this triumph, he returned to Tollgate Farm, Bunwell, on Sunday, and added two more to his bag”.
The rediscovery of that envelope brought back a lot of memories. As for the coypu – they were finally eradicated from Norfolk by 1989 and another chapter in our agricultural history came to a close.