Periodic solutions of a predator-prey system with stage-structures for predator and prey (Q1763796)

The authors consider a population predator-prey model, where predators are classified into two groups of mature and immature individuals and preys are classified into the similar two groups. The resulting system has four components. Its coefficients of the linear and quadratic terms are presumed to be periodic in time to account for seasonal phenomena. The author proves the existence of a positive periodic solution provided that minima and maxima of the coefficients satisfy a particular inequality. The proof is based on degree arguments in the form of the coincidence degree due to Gaines and Mawhin.