Proceedings of the Vertebrate Pest Conference

Field trials involving two chemical bird frightening agents are described. DRC-736-treated cracked corn was tested in feedlots in Colorado to reduce damage by redwinged blackbirds, and it was considered to be very effective. Sharp reductions in bird numbers occurred immediately after each baiting, and populations at feedlots remained very low for several weeks after treatment. 4-aminopyridine (DRC-1327) was evaluated in reducing blackbird damage to ripening corn using two different methods, either spraying ears or using broadcast baits, and in both trials was successful. Only a few frightened birds were needed in a field to frighten away others in the flock.