Attraction and Avoidance between Predators and Prey at Wildlife Crossings on Roads

Wildlife passages—infrastructural interventions designed to mitigate landscape fragmentation caused by anthropogenic linear developments—have long been predicated upon the assumption that faunal assemblages utilize these structures independently, devoid of interspecific behavioral modifications. However, emergent empirical evidence challenges this foundational premise, suggesting that trophic interactions may fundamentally subvert the intended functionality of such crossings by establishing ecological traps wherein predatory species strategically exploit concentrated prey movements or, conversely, wherein prey taxa exhibit pronounced behavioral aversions to structures bearing olfactory signatures of predation risk.​

Through occupancy modeling incorporating spatiotemporal covariance matrices across 113 crossing structures monitored over 2076 passage-days, researchers discerned statistically significant deviations from stochastic independence in approximately one-fifth of predator-prey dyads concerning spatial congruence and in two-thirds of dyadic relationships pertaining to diel synchronicity. The mathematical formulations—wherein φ (spatial co-occurrence parameter) equals ΨAB/(ΨA × ΨB) and δ (temporal co-occurrence parameter) equals rjAB/(rjA × rjB)—revealed multiplicative probabilities diverging substantially from unity, with values exceeding 1.0 indicating aggregative tendencies suggestive of predatory prospecting behaviors, while fractional values below unity denoted avoidance mechanisms consonant with threat-sensitive antipredator responses calibrated to body-size congruencies between consumers and consumed organisms.​

The implications of these findings are manifold and troubling. Rat-sized rodents demonstrated marked spatial and temporal segregation from mustelids (φ = 0.745, δ = 0.864), suggesting active avoidance of structures frequented by their primary predators. Conversely, lagomorphs exhibited pronounced spatiotemporal overlap with badgers (φ = 1.59, δ = 2.25), indicating that predators may be attending crossings to intercept prey. Such patterns, consistent with the threat-sensitive predator hypothesis, suggest that these anthropogenic bottlenecks may paradoxically function either as demographic sinks through elevated predation pressure or as functionally obsolete infrastructure through prey-mediated abandonment.​

Nevertheless, the correlative nature of this study precludes definitive causal attribution, and alternative explanations merit consideration. The observed co-occurrences might simply reflect matching habitat preferences rather than active predatory strategizing, though the systematic consistency between spatial and temporal patterns militates against this interpretation. Moreover, the ramifications extend beyond mere population dynamics to encompass genetic isolation, altered dispersal corridors, and reconfigured ecosystem processes, particularly in systems where introduced predators lack coevolutionary histories with indigenous prey.​

The conservation implications demand urgent attention. Two ameliorative strategies emerge: increasing the density and width of crossing structures to dilute predator-prey encounter probabilities, and incorporating structural heterogeneity—logs, rocks, refuges—within passages to stabilize predator-prey interactions by providing prey with escape opportunities. Until more manipulative field studies and long-term population analyses illuminate these dynamics comprehensively, the efficacy of wildlife passages as mitigation tools remains equivocal, and the "road ecosystem" continues to function as an unintended arena for predation that may compromise metapopulation connectivity objectives.

SOURCE- MDPI ARCHIEVES

WORDS COUNT- 450 

F.K SCORE- 14.6