Stimulus control of predatory behavior in the brown tree snake (Boiga irregularis). IV. Effect of mammalian blood.

Brown tree snakes (Boiga irregularis) from Guam were exposed to mammalian (Rattus norvegicus) blood on cotton-tipped applicators. Water and other control substances were similarly presented. All trials lasted 60 s, and the dependent variable was the number of tongue flicks emitted by the snake during the trial. In five experiments, B. irregularis responded with greater numbers of tongue flicks to blood than to control substances. This is the first study to reveal an ophidian response to internal chemicals of potential prey organisms.