U.S. Department of Agriculture: Animal and Plant Health Inspection Service


Date of this Version



Published in 31st National Sunflower Association Sunflower Research Forum.


We evaluated several registered fungicides and insecticides, and several natural compounds as candidate blackbird repellents for protecting agricultural production. We tested more than 750 red-winged blackbirds at the National Wildlife Research Center’s outdoor animal research facility in Fort Collins, CO to evaluate (1) their preference for treated versus untreated rice and sunflower seeds and (2) their consumption of seeds treated with varying concentrations of candidate repellents. Concentrations were varied between 10% and 200% of labeled application rates. With few exceptions, blackbirds discriminated between untreated seeds and seeds treated with one of the candidate repellents. We observed greatest repellency with caffeine + sodium benzoate, GWN-4770, Lorsban, and Tilt. Additional lab efficacy tests are planned for anthraquinone seed treatments, Flock Buster repellent, and Cobalt insecticide. Field residue and efficacy tests are also needed to evaluate and develop promising foliar repellents for protection of ripening crops.