Exploring the cascading effect of fear on the foraging activities of prey in a three species Agroecosystem
Department of Mathematics & Computing, Indian Institute of Technology (ISM), 826004, Dhanbad, Jharkhand, India
Accepted: 1 September 2021
Published online: 27 September 2021
Fear of top predators may be as or more important than direct killing in causing trophic cascades. The mere presence of top predators gives rise to a “landscape of fear”, buffering lower trophic levels from overconsumption by herbivores. In the present work, we have proposed a three-species food chain model of wolf spiders (top predator), insect pests (herbivores), and plant community interactions incorporating the cost of fear of wolf spiders in the predation rate of insect pests. It is assumed that some of the insect pests migrate due to the fear of wolf spiders. Positivity, boundedness, and parameter regimes for an ecologically realistic parameter set is identified. We have derived the local and global stability conditions for the proposed system. The existence of Hopf-bifurcation, direction and stability conditions of the bifurcating periodic solutions have been discussed. It is observed that the fear of wolf spiders has a stabilizing impact on system dynamics. It contributes positively to the role of wolf spiders as a biocontrol agent. One and two-parameter bifurcation diagrams have been plotted. It is observed that fear level decreases with an increase in the migration rate and for relatively large values of conversion rate, insect pests become less sensitive toward the perceived predation risk.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2021