Date of this Version
Today, more than ever, there is an increasing need for non-lethal methods to effec- tively control crop depredation by birds. One such method, involving the use of fear- provoking stimuli, has been used since ancient times but often with little success. If fear-provoking stimuli are to be improved, we must identify those features that are most effective and incorporate these into scare devices. Models of raptors are promising fear-provoking stimuli (Rowe 1971, Brown 1974, Messersmith 1975, Blokpoel 1976). Unfortunately, birds usually habituate to these models rather quickly. More efficient models have not been devised, in part because of the lack of experimental studies on predator models and other fear-provoking stimuli. Therefore, I have examined the effectiveness of three predator models by quantifying how birds respond when exposed to them for various lengths of time.