Trap Function and Overview of the Trapping Process

Abstract

Traps are devices that delimit the displacement of previously free-ranging entities in space through time. Examples of traps used for prey capture by organisms other than humans are spider webs, ant-lion traps, and the Venus fly trap. Traps offer efficiencies to their makers by concentrating the target organisms. They can also remove pests from the system, thereby offering direct control. A key feature of all trapping is intersection of a trap with its targets at some point in space. Because traps are typically stationary, it is their targets that must move so as to either approach the trap by a chance encounter or be lured there after chance encounters with attractive cues emitted by the trap. For random walkers, the sampling radius of a trap is comprised by the maximum net dispersive distance of the target organisms over the trapping interval plus attractive plume reach. Key parameters influencing the number of targets caught from any specified distance of origin from the trap are the probabilities that the trap is found (findability) and that the organism is captured after arriving at the trap (efficiency) and retained (retention) until harvested. Total catch is given by findability × efficiency × retention per distance multiplied by the number of animals present at the given distance.