Colluding rhino poachers exploit space–time variation in opportunity and risk

Abstract

Human behavior shapes both our impact on nature and the success of solutions to safeguard it. We used crime opportunity and deterrence theory, together with methods from epidemiology, to link space–time patterns in 560 rhino poaching incidents (2011–2021) to poacher and ranger behavior in a South African rhino stronghold. Poaching activity was significantly associated with proximity to ranger camps. Together with supplementary evidence we present from internal investigations, this suggests that criminal syndicates collude with some rangers to facilitate poaching. Poachers repeatedly targeted specific regions of the reserve for set periods before shifting, mirroring the “near-repeat” behavior observed for other crimes. Poachers also avoided tourist activity and minimized time on the reserve. Results suggest poachers strategically leverage space–time variation in opportunity and risk. Solutions based on these behavioral insights include early response to space–time clusters of poaching, spatially targeted implementation of rhino dehorning, and bolstering ranger resilience to the corrupting influence of criminal syndicates.