Figure 3From: Optimal control problem arises from illegal poaching of southern white rhino mathematical modelThe effects of the changes in parameter \(\alpha ^{*}\). The blue curve (stable to \(\mathcal{E}_{1}\)) represents that it takes 11 years for white rhino to become adult, the black curve (stable to \(\mathcal{E}_{2}\)) represents that it takes 7 years, while the red curve (stable to \(\mathcal{E}_{3}\)) represents that it takes 3 yearsBack to article page