Mark–recapture of Agriotes obscurus and Agriotes lineatus with dense arrays of pheromone traps in an undisturbed grassland population reservoir

Abstract

Abstract The present study was conducted using mark–released populations of male Agriotes obscurus (AO) and Agriotes lineatus (AL) adults to simulate the spatial and temporal capture rates of wild beetle populations in dense arrays of pheromone traps in a confined, nonfarmed habitat. Two parallel rows of traps, spaced 3 m apart along corridors of grassy dyke, recaptured 85.6% of AO and 77.8% of AL with arrays of their respective pheromone traps, mostly within the first week of release. In arrays of mixed AO and AL traps, recapture rates were 77.8% and 83.3%, respectively. In arrays with only AO traps, 31.2% of AL males released within the arrays mistakenly entered the AO traps, which declined to only 2.2% when released in arrays with both AO and AL traps. In arrays with only AL traps, only 0.7% of released AO were mistakenly taken in the AL traps, and only 0.3% mistakenly entered AL traps in mixed AO and AL trap arrays. Between 34.4–38.9% of AO and 21.1–25.6% of AL released in areas immediately adjacent to the trapping arrays were caught, mostly in the outermost traps. The implications of these results for determining the efficacy of mass trapping as a click beetle management approach are discussed.