Abstract
In this paper, we are concerned with the role of the age structure of a prey
in the dynamic of a predator prey model. Specifically, we study the effect of predation
on a non-reproductive class of the prey, when the reproductive class of the prey presents
a group defense mechanism. Three different scenarios are analyzed: (1) Constant
predation rate on the nonreproductive class, no defense mechanism; (2) Predation
of Type II of Holling on the non-reproductive class, no defense mechanism; and (3)
Predation of Type II of Holling on the non-reproductive class, defense mechanism.
