False Exclusion: A Case to Embed Predator Performance in Classical Population Models.

Area of Science:

• Ecology
• Theoretical Ecology
• Mathematical Biology

Background:

• Classical predator-prey models, such as Lotka-Volterra, primarily incorporate prey-dependent ingestion rates.
• Other crucial prey-dependent predator responses have been largely excluded from ecological models.
• These neglected factors can significantly influence population dynamics.

Purpose of the Study:

• To investigate the impact of previously excluded prey-dependent predator responses on ecological dynamics.
• To introduce empirically derived functions for nonlinear predator behaviors into existing models.
• To reevaluate classical assumptions in predator-prey theory.

Main Methods:

• Experiments were conducted using model zooplankton to derive empirical functions for predator responses.
• These functions were integrated into a generic predator-prey model.
• Bifurcation analysis and parameter space exploration were used to assess model dynamics.

Main Results:

• Including nonlinear, prey-dependent predator responses altered model predictions significantly.
• Revised models predicted predator extinctions or survival in scenarios where classical models did not.
• Model stability was enhanced, with smaller amplitude population cycles compared to classical models.

Conclusions:

• Classical predator-prey models may provide incomplete predictions due to excluded prey-dependent responses.
• Incorporating factors like predator efficiency, resource allocation, and mortality rates improves ecological model realism.
• Reevaluation of predator responses to prey abundance is crucial for accurate ecological forecasting.