Predators use volatiles to avoid prey patches with conspecifics

摘要: 1. Simple models of optimal foraging, such as ideal free distribution models, are based on the assumption that foragers omniscient with respect to quality all patches in environment; they know how much food and many competitors present each patch. 2. In contrast, simple population dynamic treat predator-prey distributions a phenomenological way, do not take fitness consequences for individual into account. Yet, precise way which these come being is what really matters dynamics. It therefore necessary study behavioural mechanisms underlying over patches. 3. We studied behaviour predatory mite, Phytoseiulus persimilis, response prey occupied by conspecifics. well known high predator densities promote dispersal mites. Our question was extent predators can assess presence conspecifics from distance. 4. Experiments Y-tube olfactometer showed mites avoid 5. This avoidance cannot be attributed odours conspecific predators, or damaged predation, odour sources both appear attractive. 6. Separating patch source led only when were positioned upwind patch, downwind. suggests release an elicits production yet another prey. supported observation removal adult quick disappearance response. 7. argue distant discrimination between without competing may quite common among parasitoids, use instead physical inspection allows instantaneously integrate information competitors. 8. mechanism bring parasitoids closer behaving than previously thought possible.