Comparing Methods for Measuring Predation: Toward a Quantitative–Informative Indicator of Natural Pest Control

ABSTRACT The transition to insecticide‐free pest management requires field‐based measurements of natural regulation capturing trophic networks driving pest suppression. Conventional proxies (pest abundance, predator abundance, and richness) fail to quantify actual predation or species contributions. A quantitative–informative indicator must couple trophic interactions, spanning specialist to generalist predators, with specific predation rates (daily prey consumed per predator). We evaluated major predation quantification methods in relation to their potential to inform such an indicator. These included four direct approaches (predator observation, sentinel prey, exclusion devices, predation signs), two indirect approaches (prey remains and molecular traces in predator guts), and three inferential approaches (trait‐based analyses, population dynamics modelling, and inference from molecular prey detection). Seven criteria guided the comparison: type of predation measurement, taxonomic resolution for prey and predators, capacity to reveal trophic links, applicability across predator diversity, generality of results, and practical feasibility. We also compared the few approaches for converting molecular detection data into quantitative estimates of predation. Our synthesis highlights inference from molecular prey detection as the most promising and versatile method, as it simultaneously reveals trophic interactions and yields data that can be translated into predation rates. In contrast, common methods such as exclusion devices provide broad estimates of pest suppression but obscure trophic complexity, limiting ecological insight and constraining targeted management in favor of the most effective predator species. Integrating molecular detection with modeling inference emerges as a robust way to estimate predation rates on multiple pests across entire predator communities. This combination offers a powerful framework for developing a biological control indicator, though practical implementation will require improved molecular assays and more effective sampling strategies in the field.