Method Useful for predators, parasitoids, or both Measures consumptive effects? Measures non-consumptive effects?
Artificial sentinel prey models (e.g., clay caterpillars) evaluated for removal or marks of attack mostly predators
Live tethered or outplanted sentinel prey/hosts (usually immobile stages, like eggs or pupae; but also confined larval stages) both
Post-hoc assessment of natural enemy impact via detection of bite-marks or other physical damage to prey predators
Post-hoc assessment of natural enemy impact via detection of distinctive host remains, host-feeding tubes or damage, remains of developing parasitoids (egg chorions, larval or pupal exuvia, meconia, cocoons), or distinctive parasitoid or host emergence holes parasitoids
Dissection of hosts to record parasitoid eggs, larvae, or pupae; or rearing of hosts parasitoids
Monoclonal antibody-ELISA or DNA-based assays of hosts to detect internally developing parasitoids parasitoids
Gut content analyses – detection of prey remains using simple dissections and visual inspection predators
Monoclonal antibody-ELISA, immunomarking, or DNA-based assays of consumer gut contents predators and host-feeding parasitoids
Focal observations of prey/hosts, using human observers or video cameras both Partially*
Field life table construction by repeated sampling of a cohort of developing hosts/prey to quantify survival and rate of development from eggs to adults; often used with immobile hosts/prey both Partially†
Short-term (i.e., too short for prey reproduction) mesocosm assays using hand removal or caging treatments to contrast the effects of natural enemy presence/absence; response variable = prey survival both Partially†
Long-term (i.e., long enough to permit substantial prey reproduction) mesocosm assays using hand removal or caging treatments to contrast the effects of natural enemy presence/absence; response variable = prey population size or growth rate both
Experimental removal of natural enemy populations using selective insecticides; response variable = prey/host population size or growth rate both
Experimental addition of natural enemy populations by controlling ants that otherwise exclude the nature enemy; response variable = prey/host population size or growth rate both
Observational field methods comparing natural enemy present vs. absent (e.g., in classical biocontrol settings: pre- vs. post-release, or release site vs. non-release site); response variable = prey/host population size or growth rate‡ both