Exposure of birds to cholinesterase-inhibiting pesticides following a forest application for tick control

A mixture of malathion (4%), carbaryl (2%) and cypermethrin (4%) was applied as dry powder to forest and grasslands at a rate of 5 kg/ha for tick control in 1500 ha of a deer hunting estate in the south of Spain. The effect on plasma cholinesterase (ChE) of house sparrow and nightingale, and brain ChE of red-legged partridge was studied. Plasma ChE was lower after the treatment in passerine birds, but brain AChE was not affected in partridges. The body condition of house sparrows was significantly lower after the treatment.M. Martínez-Haro was supported by a postgraduate grant (I3P) from Consejo Superior de Investigaciones Científicas and the participation of FEDENCA (Fundación para el Estudio y la Defensa de la Naturaleza y la Caza). This study was supported with a grant of the Spanish Ministry of Education and Science (CGL2004-02568/BOS).Peer reviewe