The decline of the corncrake crex crex in britain continues

Abstract

A census of singing Corncrakes throughout Britain was carried out in 1993. Ten-kilometre National Grid squares in Scotland which held the species in 1978/79 and/or 1988 were searched systematically by night. Elsewhere records of singing birds were obtained by means of publicity andchecked for accuracy. A total of 480 singing males was counted in 83 10-km squares. Ninety-twoper cent of the population was found in the Hebridean Islands. The total count was 17% smallerthan in 1988 and at least 34% less than in 1978. The average rate of population decline between 1988 and 1993 was 3.5% per year, which was more rapid than during the previous 10 years. There were considerable differences among islands and areas in the rate of change of the Corncrake population. In some areas the population had increased, but in Orkney there had been an 82% decline in 5 years. Areas with high rates of decline between 1978 and 1988 also tended to showrapid declines between 1988 and 1993. The census results and conservation measures are discussed in the context of other studies of factors associated with the decline. The evidence available is consistent with the idea that improved management of habitats on the breeding grounds offers the best prospects for recovery. A recent development is the occurrence of small numbersof Corncrakes (6) on set-aside land on arable farmland in England and Scotland. The conditionsunder which this new habitat could be used more extensively by Corncrakes are discussed. © Taylor & Francis Group, LLC.