Two-Parameter Bifurcation in a Predator]Prey System of Ivlev Type*

Our concern is to consider an ecological system with Ivlev’s functional response 1yeya x of predator to prey. In addition to a, this system contains parameters r and D, which represent the intrinsic rate of increase for the prey population and the death rate for the predator population, respectively. A necessary and sufficient condition for the uniqueness of limit cycles of the predator]prey system is presented. This result gives the bifurcation curve in the a, D.-plane.