L\'evy flight movements prevent extinctions and maximize population abundances in fragile Lotka Volterra systems

TL;DR

This study shows that scale-free Le9vy flight movements can prevent extinctions and enhance population stability in fragile predator-prey systems by balancing exploitation and regeneration in fragmented habitats.

Contribution

It demonstrates how intermediate Le9vy flight strategies optimize population resilience and coexistence in complex ecological models, a novel insight into movement ecology.

Findings

Le9vy flights prevent predator extinction in fragile systems.

Intermediate Le9vy index balances exploitation and regeneration.

Superdiffusive Le9vy flights lead to extinction due to overexploitation.

Abstract

Multiple-scale mobility is ubiquitous in nature and has become instrumental for understanding and modeling animal foraging behavior. However, the impact of individual movements on the long-term stability of populations remains largely unexplored. We analyze deterministic and stochastic Lotka Volterra systems, where mobile predators consume scarce resources (prey) confined in patches. In fragile systems (that is, those unfavorable to species coexistence), the predator species has a maximized abundance and is resilient to degraded prey conditions when individual mobility is multiple scaled. Within the L\'evy flight model, highly superdiffusive foragers rarely encounter prey patches and go extinct, whereas normally diffusing foragers tend to proliferate within patches, causing extinctions by overexploitation. L\'evy flights of intermediate index allow a sustainable balance between patch exploitation and regeneration over wide ranges of demographic rates. Our analytical and simulated results can explain field observations and suggest that scale-free random movements are an important mechanism by which entire populations adapt to scarcity in fragmented ecosystems.