overpredation

Overpredation describes a situation in which predation pressure on a prey population is excessive relative to the prey’s ability to reproduce and recover, leading to declines that may outpace natural fluctuations. It is not a formal ecological term but a way to describe imbalances in predator–prey dynamics where predation overwhelms prey populations.

Causes of overpredation include natural cycles of predator and prey populations, as well as human-induced factors. Habitat loss and fragmentation can reduce refugia for prey, while climate change can shift predator and prey distributions. The removal or depletion of alternative prey can force predators to concentrate on a single prey species, and the introduction of nonnative predators or competitors can alter food webs. Disease, high predator densities sustained by abundant resources, and changes in fishing or land-use practices can also contribute.

Ecological consequences can be significant. Sustained high predation can drive prey populations to local or regional declines or extinctions, reduce genetic diversity, and trigger trophic cascades that alter vegetation, invertebrate communities, and ecosystem processes. These changes may affect ecosystem services, such as pest regulation, pollination, or fisheries, and can reduce biodiversity.

Examples are often discussed in island and marine contexts, where introduced or unmanaged predators can impose strong predation pressure on native prey. In such settings, management may require predator control, restoration of prey habitats and refuges, or ecosystem-based approaches that consider the needs of multiple species.

Management and research emphasize monitoring, adaptive management, and precautionary action to prevent or mitigate overpredation while maintaining ecological balance.