Chaotic dynamics in a simple predator-prey model with discrete delay
Abstract
A discrete delay is included to model the time between the capture of the
prey and its conversion to viable biomass in the simplest classical Gause type
predator-prey model that has equilibrium dynamics without delay. As the delay
increases from zero, the coexistence equilibrium undergoes a supercritical Hopf
bifurcation, two saddle-node bifurcations of limit cycles, and a cascade of
period doublings, eventu1ally leading to chaos. The resulting periodic orbits
and the strange attractor resemble their counterparts for the Mackey-Glass
equation. Due to the global stability of the system without delay, these
complicated dynamics can be solely attributed to the introduction of the delay.
Since many models include predator-prey like interactions as submodels, this
study emphasizes the importance of understanding the implications of
overlooking delay in such models on the reliability of the model-based
predictions, especially since the temperature is known to have an effect on the
length of certain delays.