CHEMICAL REPELLENTS FOR REDUCING CROP DAMAGE BY BLACKBIRDS

Chemical repellants are intended to prevent birds from feeding on a particular food (the crop) at a given location. To be considered effective, a chemical repellent must produce 1 of 2 responses (1) depredating birds remain but feed on an alternative non-crop food item or (2) depredating birds leavc and go elsewhere to feed. The search for a safe, cost-effective chemical repellent has spanned decades. During the 1950s, 196Os, and 199Os, repellent screening programs, using captive red-winged blackbirds (Aaelaius Dboeniceus), brown-headed cowbirds (Molorhrus ater), and European starlings (Sturnus vulgaris), identified numerous potentially useful compounds. Despite promising results from trials with captive birds and verification in subsequent field trials, formal registration of bird repellant chemicals for crop protection has remained elusive. In this paper, we present recent results from cage and field trials of various candidate compounds and discuss the potential utility of chemical repellents within integrated blackbird management strategies