Interspecific interaction among mammals in Panna Tiger Reserve, central India: Prey-predator dynamics

Abstract

Interspecific interactions play a critical role in shaping ecosystem structure, species assemblages, and food web dynamics. Specifically, carnivores often exert top-down regulatory control on ecological communities, and the loss of apex predators can lead to profound changes in community composition and ecosystem function. Thus, carnivore reintroduction (trophic rewilding) has gained prominence as a strategy to restore ecological balance. However, the success of such efforts is contingent upon the availability of a sufficient prey base capable of supporting growing carnivore populations, underscoring the significance of bottom-up regulatory processes. Furthermore, species composition and assemblage patterns are strongly influenced by environmental variables and landscape characteristics. In this study, we examined the mammalian community of Panna Tiger Reserve (PTR) to evaluate the relative roles of top-down and bottom-up regulation in shaping mammalian assemblages. We utilized camera trap data from two seasons (2019) and constructed hypothesis-driven interaction pathways representing both regulatory processes within a piecewise structural equation modeling (SEM) framework. The results demonstrated that both top-down (carnivore-driven) and bottom-up (prey-driven) mechanisms significantly influence community structure. Additionally, environmental factors and habitat features were found to be critical drivers affecting the spatial distribution of both predators and prey. Importantly, our findings highlight the dominant influence of top-down effects in species community, however, bottom-up regulation in facilitating the successful reintroduction and population recovery of tigers in PTR, despite the presence of a high density of co-predators. This underscores the essential role of prey abundance and habitat quality in supporting large carnivore conservation. Overall, this study provides key insights into trophic rewilding and emphasizes the importance of maintaining intact habitats, conserving prey populations, and promoting coexistence within multi-species communities.