Repellency and Toxicity of Three Bird Control Chemicals to Four Species of African Grain-Eating Birds

Abstract

Birds damage thousands of tons of ripening cereal grains worth millions of dollars annually in Africa. In Sudan, Denver Wildlife Research Center (DWRC) personnel are working with the Ministry of Agriculture to reduce crop losses to depredating birds. Although the red-billed quelea (Quelea quelea) is the primary pest in most of the countries, many other species also cause severe damage (Anon. 1980). In Sudan these other species include village weavers (Ploceus cucullatus), golden sparrows (Passer luteus), red bishops (Euplectes orix), and occasionally masked weavers (Ploceus taeniopterus). The control measures used by the Sudan Plant Protection Department are directed at population reduction of highly gregarious species (such as quelea) through the aerial application of the avicide fenthion (O,O-Dimethyl O-[3-methyl4-(methylthio)phenyl]phosphorothioate). Because of the potential primary and secondary poisoning problems posed by fenthion, development and application of an alternate control chemical is desirable. Our objective was to determine the susceptibility of 4 species of birds (which damage cereal crops in Sudan and certain other African countries) to 3 chemicals regularly used in bird damage control in the United States (Dolbeer 1980): the avicide, Starlicide (3-chloro-4 methylbenzenamine); the repellent, methiocarb (3,5-dimethyl-4-(methylthio)phenyl methylcarbamate); and the frightening agent, Avitrol (4-aminopyridine). Our laboratory tests were designed to indicate the potential of Starlicide as an avicide in Africa, help explain the variable results obtained with methiocarb, and provide a basis for initiating field trials with Avitrol.