Ecological system with fear induced group defence and prey refuge

Shivam Yadav; Jai Prakash Tripathi; Shrichand Bhuria; Satish Kumar Tiwari; Deepak Tripathi; Vandana Tiwari; Ranjit Kumar Upadhyay; Yun Kang

arXiv · 2302.04594

Ecological system with fear induced group defence and prey refuge

Shivam Yadav·Jai Prakash Tripathi·Shrichand Bhuria·Satish Kumar Tiwari·Deepak Tripathi·Vandana Tiwari·Ranjit Kumar Upadhyay·Yun Kang

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Abstract

In this study, we investigate the dynamics of a spatial and non spatial prey-predator interaction model that includes the following: (i) fear effect incorporated in prey birth rate; (ii) group defence of prey against predators; and (iii) prey refuge. We provide comprehensive mathematical analysis of extinction and persistence scenarios for both prey and predator species. To better explore the dynamics of the system, a thorough investigation of bifurcation analysis has been performed using fear level, prey birth rate, and prey death rate caused by intra-prey competition as bifurcation parameter. All potential occurrences of bi-stability dynamics have also been investigated for some relevant sets of parametric values. Our numerical evaluations show that high levels of fear can stabilize the prey-predator system by ruling out the possibility of periodic solutions. Also, our model Hopf bifurcation is subcritical in contrast to traditional prey-predator models, which ignore the cost of fear and have supercritical Hopf bifurcations in general. In contrast to the general trend, predator species go extinct at higher values of prey birth rates. We have also found that, contrary to the typical tendency for prey species to go extinct, both prey and predator populations may coexist in the system as intra-prey competition level grows noticeably. The stability and Turing instability of associated spatial model have also been investigated analytically. We also perform the numerical simulation to observe the effect of different parameters on the density distribution of species. Different types of spatiotemporal patterns like spot, mixture of spots and stripes have been observed via variation of time evolution, diffusion coefficient of predator population, level of fear factor and prey refuge. The fear level parameter (k) has a great impact on the spatial dynamics of model system.

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Shivam Yadav, Jai Prakash Tripathi, Shrichand Bhuria, Satish Kumar Tiwari, Deepak Tripathi, Vandana Tiwari, Ranjit Kumar Upadhyay, Yun Kang. 2023-02-09. Ecological system with fear induced group defence and prey refuge. https://arxiv.org/abs/2302.04594

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