The impact of invasive species on some ecological services in a harvested predator–prey system

Abstract

Biological invasion is a critical and emerging problem in the ecosystem as it has been the reason for the extinction and endangeredness of several species. Besides, harvesting on the different trophic levels also substantially impacts the dynamics of several interacting species. For this, we have considered a mathematical model consisting of prey, a predator, and an invasive species with Holling type II functional response and nonlinear harvesting to study the dual impact of harvesting and the presence of invasive species. Our results show that in the case of prey harvesting only, increasing effort on prey promotes the yield but reduces resilience. Whereas for the predator harvesting only, the intermediate effort level on the predator supports both the services simultaneously. In the case of joint harvesting of both species, predator-oriented harvesting gives more yield and resilience at the MSY level. Therefore, we conclude that the optimal yield and resilience in invasive species induced predator–prey systems can be found for the case predator or predator-oriented harvesting system with low predator catchability only. We also note no significant variation in the biomass, yield, and resilience between the linear and nonlinear models concerning the above cases except the number of equilibria and the specific ecosystem services. Invasions always harm the biological conservation of the ecosystem.