BREIF HISTORY OF THE AMERICAN CRAYFISH IN THE UK

American Signal crayfish often carry the crayfish plague (a.astaci), to which they are immune, but which kills non-American crayfish within weeks. The crayfish plague had been a growing problem across Europe since the late 19th century but was not understood properly. Crayfish-loving Sweden had begun to suffer losses of their native Noble crayfish and, in the late 1960s, imported American Signal crayfish which were known to be immune to the plague. It was not understood that American crayfish were, nonetheless, potential carriers. This soon became apparent, but not until American Signal crayfish had also been introduced to the UK by our Government. As the Swedish project seemed to be going well, MAFF (Ministry of Agriculture, Forestry and Fisheries) introduced American Signal crayfish to the UK in 1976. It was expected that farming them, to supply the lucrative Scandinavian market, would create a good export business, and grants were made available to encourage estate owners and aquaculturists to engage in the project. Large quantities of American Signal crayfish were imported from Swedish stock and distributed to hundreds of waters across England (and pursuantly to endless pet shops, fish tanks, fishmongers, and kitchens). If the Government had wanted to introduce a deadly national epidemic, they could not have made a better job of it. Sure enough, over the last thirty years, the majority of our native White-clawed crayfish have been wiped out. Unwittingly, MAFF had blindly rushed into causing an environmental disaster for the sake of an illthought out business plan. The new crayfish farms had to wait for at least four years before their first annual harvest, by which time crayfish prices had dropped dramatically. Other countries had also seen the same opportunity and places like China were now exporting very cheap crayfish. There was suddenly such an abundance of crayfish that competition was strong and prices low. The UK farms were soon competing with wandering trappers who sourced wild stock at a fraction of the farmed costs. Under these conditions farming crayfish was uneconomical and most such businesses stopped, leaving massive populations of crayfish unmanaged, often given easy access to the wider environment as sites were redeveloped. No serious action was taken by the Government to control the problem, while they possibly still stood a chance. The few advisers who understood the problem were unlikely to have urgently pushed for costly action to a clean up a mess that they had just made. That would have drawn attention to their errors, questioned competence, demanded answers and fall-guys and scapegoats, etc.. So, if there was ever an opportunity to control the crayfish spread, it was soon gone. It was deemed better to observe the crayfish problem develop and hold regular meetings to discuss the best way to deal with them. Those meetings continue to this day.