Data from: Why do top predators engage in superpredation? From an empirical scenario to a theoretical framework

Lethal interactions can shape ecosystem structure, and consequently
understanding their causes is ecologically relevant. To improve both
empirical and theoretical knowledge on superpredation (i.e. predation on
high-order predators), we studied an eagle owl population, including its
main prey and mesopredators, and then we crossed these results with
existing theories to provide a reasoning framework. We fitted our field
data into four main causes explaining lethal interactions: food stress,
opportunistic superpredation, removal of a competitor, and removal of a
potential threat. Empirically, superpredation seemed to be mostly
determined by the combination of the food-stress and
opportunistic-superpredation hypotheses, which highlights the complexity
of the factors triggering superpredation. Therefore, besides being a
response to lower food availability, superpredation may also represent an
effective mechanism to remove potential predators and/or competitors,
either intentionally or not. Our theoretical framework focused on the
decision-making process in superpredation, considering four inter-related
stages: encountering; attacking; and capturing a mesopredator; as well as
consuming a mesopredator once killed. Superpredation almost certainly
results from a complex process of decision-making, accounting for costs
and benefits assessed moment-to-moment and for each mesopredator
individual. It is time to build bridges between theoretical and empirical
studies to further understand the mechanisms driving complex interactions
among top predators and mesopredators.