CHEMICAL REPELLENTS AND PLASTIC NETTING FOR REDUCING BIRD DAMAGE TO SWEET CHERRIES, BLUEBERRIES, AND GRAPES

We conducted 3 years of field tests comparing two chemicals [methyl an thranilate (MA, a natural compound used as a flavor additive) and Keyp lex-350 (a proprietary micronutrient formulation)] that were reported to repel birds to exclusionary plastic netting and nontreated plots. C umulative fruit damage from birds was monitored on sweet and tart cher ry (Prunus avium L. and P. cerasus L.), blueberry (Vaccinium corymbosu m L.), and wine grapes (Vitis vinifera x labrusca). Initial MA formula tions caused injury to fruit and foliage. Two modified MA formulations with microencapsulation and photooxidation inhibitors provided signif icant reductions in bird damage and fruit splitting on sweet cherries in one of four experiments. A taste panel could not detect MA residues on sweet cherries at harvest. Bird damage was slightly reduced in MA- treated grapes, but damage to blueberries was similar in MA and contro l treatments. Keyplex did not deter birds from feeding on fruit and ca used blemishes on and an unpleasant flavor in treated fruit. Many bird species were observed feeding on these fruit crops during successive years at the three experimental sites. Although these two chemicals ha ve the potential to deter bird depredation, our work suggests that nei ther is consistently effective against all the frugivorous species in the northeastern United States. Chemical name used: 2-Aminobenzoic aci d methyl ester [methyl anthranilate (MA)].