Does the influence of anthropic impacts reflect on the predator-prey relationship?

Abstract

The predator-prey interactions present in communities influence their composition and structure, acting as a controlling force in the spatial and temporal dynamics of populations. In this context, we aimed to evaluate the influence of environmental impacts on the interaction dynamics between predators and prey in environments with different qualitative characteristics. To this end, we collected macroinvertebrates (prey) and fish (predators) in four sampling sites with distinct seasonal periods. Correlation analyses were performed between predators and prey in different scenarios and, afterwards, the type of relationship, positive or negative, was evaluated. However, in our results more positive relationships were found than negative, which may indicate that predation directly affects other types of ecological relationships between prey groups. More significant relationships were exhibited in the upstream versus downstream regions. This fact may be linked to the anthropic impacts observed downstream. In summary, the relationship between predator-prey interactions and environmental quality, predicted in the initial hypothesis, was corroborated, in which upstream regions (with better qualitative characteristics) exhibited this relationship more stable than downstream regions.