Global Dynamics of a Fisheries Economic Model with Gradient Adjustment

Taking into account the nonlinear demand function, we have developed a multi-agent fishery economic model, where a multitude of agents are bounded by rationality. The fishing decisions of these agents are driven by a profit gradient mechanism. To assess the local stability of the system, stability analysis is performed with the Jury criterion. The investigation has revealed the presence of two conventional paths to chaos, namely, the flip bifurcation and the Neimark-Sacker bifurcation. This was achieved by mapping the stability regions and stability curves of the Nash equilibrium. The multistability of the system is further explored on two-dimensional planes on which the influence of joint parameters on the system's stability is demonstrated. The existence of Arnold's tongue has demonstrated unparalleled complexity and intricate interactions across different scales of the system. Both critical curves and basins of attraction are illustrated to gain insight into global bifurcations. The chaotic attractor is found to be confined within specific boundaries. The findings clearly show higher maximum instantaneous demand, relatively slower adjustment speed, and lower price sensitivity. Arguably, a controlled cost would lead to sustainable fishing resources. Moreover, the results also suggest that the agents would benefit more from confined conditions.