No abstract

The degradation of coral reefs is becoming increasingly alarming. If left unchecked, there will be an imbalance of the marine ecosystem. Many factors are killing the coral reefs. There is nature factor such as global warming and human activities factor such as destructive fishing. In this paper, we proposed model coral reefs with a system of the nonlinear ordinary differential equation between five populations, namely coral reefs, parrotfish, macroalgae, algal turfs, and crown of thorns starfish in the Great Barrier Reef, Coral Sea. We consider biological interactions such as predator-prey relationships between the crown of thorns starfish and coral reefs, and macroalgae grazers on coral reefs. We consider destructive fishing that damage the coral. Using the standard dynamic system theory, we determined the stability of the system with and without fishing. We show numerical simulation and sensitivity analysis to evaluate the investigation results to conclude the effect of the destructive fishery on coral reefs.