Poisoning of wild geese by carbophenothion-treated winter wheat

A series of incidents involving greylag goose (Anser anser) casualties in Angus and Perthshire and a single incident involving pink-footed goose (Anser brachyrhynchus) casualties on Humberside occurred during the winter of 1974/75. The results of post-mortem examinations and brain esterase studies were consistent with the deaths having resulted from organophosphorus poisoning. Chemical analysis revealed the presence of carbophenothion (S-4-chlorophenylthiomethyl OO-diethyl phosphoro-dithioate) residues in the gut contents and internal tissues of the casualties. It was concluded that the geese had died from carbophenothion poisoning following the ingestion of treated winter wheat seed and the factors that led to the incidents are discussed.