Aversion of the feral pigeon and the house sparrow to pellets and sprouts treated with commercial formulations of methyl anthranilate.

Two methyl anthranilate formulations, ReJex-iT TP-40 and AG-36, were tested as bird-repelling agents for animal feed and vegetable sprouts, respectively. Feral pigeons (Columbia livia) and house sparrows (Passer domesticus) are important pests of animal husbandry and field crops in Israel. In each 4-day experiment, four birds were held together in an aviary, and were offered four trays or dishes with animal feed or cauliflower sprouts in four corners of the cage. The trays and dishes were transposed daily in a Latin square sequence. Pigeons consumed significantly more untreated feed than treated feed. When no alternative untreated food was offered, there was no significant repellency. Treatment of animal feed with TP-40 to give 2.0 ml methyl anthranilate kg-1 or less had no repellent effect on sparrows. Concentrations of 4.0 ml kg-1 or more repelled the sparrows significantly. When no untreated feed was presented, pigeons and sparrows preferred the lowest concentration of methyl anthranilate presented. When AG-36 was tested on vegetable sprouts, the sparrows tended significantly to avoid the highest concentration used--14.5 ml methyl anthranilate litre-1 spray. The inter-specific differences between the birds indicate that the efficacy of methyl anthranilate formulations as a repellent has to be specified for every species. This study did not determine (1) the possibility of developing habituation, (2) the behaviour of birds under natural conditions in the field, or (3) the influence of the feeding behaviour of a sympatric bird species on the repellency of methyl anthranilate to other species.