University of Guilan Journal of Mathematical Modeling 2345-394X 3 2 2016 03 01 A model for the dynamical study of food-chain system considering interference of top predator in a polluted environment 189 218 1471 EN Om Prakash Misra School of Mathematics and Allied Sciences, Jiwaji University, Gwalior-474 011, India Raveendra Babu Annavarapu School of Mathematics and Allied Sciences, Jiwaji University, Gwalior-474 011, India Journal Article 2015 09 28 The modeling investigation in this paper discusses the system level effects of a toxicant on a three species food chain system. In the models, we have assumed that the presence of top predator reduces the predatory ability of the intermediate predator. The stability analysis of the models is carried out and the sufficient conditions for the existence and extinction of the populations under the stress of toxicant are obtained. Further, it is also found that the predation rate of the intermediate predator is a bifurcating parameter and Hopf-bifurcation occurs at some critical value of this parameter. Finally, numerical simulation is carried out to support the analytical results. https://jmm.guilan.ac.ir/article_1471_62c5a01d2ff91441d9018f8a6877e4a7.pdf