Simulating capture efficiency of pitfall traps based on sampling strategy and the movement of ground‐dwelling arthropods

International audience

إنجليزي. Pitfall traps are frequently used to capture ground‐dwelling arthropods, particularly beetles, ants and spiders. The efficiency of a pitfall trapping system strongly depends on the number opening size traps, how distributed over sampling area (spatial arrangement) movement characteristics arthropods. We use numerical simulations for single species analyse trap count patterns that emerge from these variables. Arthropod individuals is modelled as correlated random walks, with multiple placed an area, catches simulated individual interaction traps. consider four different types spatial arrangements across homogeneous landscape: grid (i.e. rectangular array), transect, nested‐cross randomised. contextualise our results by considering locomotion Pterostichus melanarius , highly active carabid beetle often serving biocontrol agent suppression pest insects weeds. By simulating randomly moving we show there optimal inter‐trap separation distance (trap spacing) maximises captures, can be expressed using exact formulae in terms sizes, number. Moreover, arrangements, larger spacing maximise coverage whole suboptimal. Also, find large hierarchical order relation efficiency: grid, randomised, followed nested‐cross. However, smaller areas, this changed rate at which counts accumulate varies arrangements—eventually saturating levels. In effects, maximised narrow diffusive range does not depend type arrangement—indicating approximate mode arthropod activity, i.e. spread. Our approach simultaneously considers several important experimental design aspects providing basis optimise adapt protocols other better reflect their various purposes, such monitoring, conservation or management.