A Stage-Structured Fishery Model for African Catfish and Nile Tilapia Feeding on Two Food Resources with Harvesting

Figure 5

Simulation results, using system (18), including only the Nile tilapia. The figures show the dependence of impact on size structure (red curve), impact on biomass (blue curve), total biomass (green curve), and yield (black curve) with respect to equal harvesting rates, i.e., . The initial values are chosen positive, and other parameter values can be found in Tables 3–5.