Nonlethal Effects of Predation: The Presence of Insectivorous Birds (Parus major) Affects The Behavior and Level of Stress in Locusts (Schistocerca gregaria)

Abstract Insect exposure to their predators can affect individuals and community processes, through direct consumption or nonlethal effects. However, the links between behavioral physiological responses stimuli needed for development of predator avoidance are not clear. We subjected desert locusts ( Schistocerca gregaria ) three treatments, using great tits Parus major as a predator. The treatments included: (1) bird —presence tit its calls, (2) call —great calls only, (3) control —absence calls. In first laboratory experiment, were offered food shelter in an open space. duration hiding versus feeding indicated responses. second same adipokinetic hormone (AKH) levels measured central nervous system (CNS) hemolymph. third experiment outdoor aviary, birds allowed fly freely over before we response. During hid significantly longer amount time fed shorter when was present played, compared only played treatment. proximity elicited significant increase AKH CNS hemolymph call/control physical affected both locusts.