The influence of vigilance on intraguild predation

Area of Science:

• Ecology
• Behavioral Ecology
• Theoretical Ecology

Background:

• Intraguild predation theory posits stability requires intermediate predators to exploit prey better and top predators to consume intermediate predators.
• Mammalian carnivore systems show top predators attacking intermediate predators without consumption, challenging existing theory.
• Behavioral responses, like altered vigilance, may maintain intraguild predation system stability.

Purpose of the Study:

• To investigate how top predator attacks on intermediate predators, without consumption, affect intraguild predation system stability.
• To model the dynamical role of prey and intermediate predator vigilance in these systems.
• To explore conditions for stable coexistence in intraguild predation with behavioral modifications.

Main Methods:

• Developed two theoretical models of intraguild predation.
• Model 1 incorporated prey vigilance.
• Model 2 incorporated intermediate predator vigilance.

Main Results:

• Stable coexistence is possible with low top predator consumption rates on intermediate predators if attack rates are high.
• Stability is achieved when top predators never consume intermediate predators only if multiple prey species are shared.
• When prey are vigilant and share two species, increased top predator attacks on intermediate predators decrease competition and prey vigilance, increasing top predator densities.

Conclusions:

• Predator and prey behavior, particularly vigilance, plays a crucial dynamical role in intraguild predation systems.
• Top predators attacking intermediate predators without consumption can be a stable strategy under specific conditions, such as shared prey resources.
• Behavioral plasticity in predator-prey interactions is key to understanding ecological stability.