Ratio-dependent Predator Prey Model Research Articles

Pattern Formation and analysis of reaction–diffusion ratio-dependent prey–predator model with harvesting in predator

A significant degree of complexity to the conventional ecological dynamic is added by studying prey–predator models with harvesting predators. The primary focus of classical models is the link between prey and predator populations, emphasizing their fundamental relationships and biological roles. A complex interaction between biological processes is shown when predator harvesting is combined with prey–predator models. This presents both opportunities and challenges for sustainable resource management. These models help the community to understand how much one can harvest without wiping out the predators or disturbing the balance of the ecosystem. In this study, spatially extended reaction–diffusion prey–predator dynamics with harvesting in predator is analyzed. The unconditionally positivity preserving scheme is applied for the numerical results. Pattern formation in the spatially extended system is also obtained. Various types of patterns like spots, stripes, and holes are observed by using extensive numerical simulations with various parameters. The numerical technique is unconditionally stable, dynamically consistent with the underlying model, preserves the positivity, has bounded behavior, and preserves the all true properties of the continuous model. The underlying model has two equilibrium points and both are successfully obtained with positive behavior for the whole domain. All the theoretical results are verified through the numerical simulations.

Dynamics for a Ratio-Dependent Prey–Predator Model with Different Free Boundaries

In this paper, we study the dynamics of the ratio-dependent type prey–predator model with different free boundaries. The two free boundaries, determined by prey and predator, respectively, implying that they may intersect with each other as time evolves, are used to describe the spreading of prey and predator. Our primary focus lies in analyzing the long-term behaviors of both predator and prey. We establish sufficient conditions for the spreading and vanishing of prey and predator. Furthermore, in cases where spread occurs, we offer estimates for the asymptotic spreading speeds of prey and predator, denoted as u and v, respectively, as well as the asymptotic speeds of the free boundaries, denoted by h and g. Our findings reveal that when the predator’s speed is lower than that of the prey, it leads to a reduction in the prey’s asymptotic speed.

Turing-Hopf Bifurcation Analysis in a Diffusive Ratio-Dependent Predator-Prey Model with Allee Effect and Predator Harvesting.

This paper investigates the complex dynamics of a ratio-dependent predator-prey model incorporating the Allee effect in prey and predator harvesting. To explore the joint effect of the harvesting effort and diffusion on the dynamics of the system, we perform the following analyses: (a) The stability of non-negative constant steady states; (b) The sufficient conditions for the occurrence of a Hopf bifurcation, Turing bifurcation, and Turing-Hopf bifurcation; (c) The derivation of the normal form near the Turing-Hopf singularity. Moreover, we provide numerical simulations to illustrate the theoretical results. The results demonstrate that the small change in harvesting effort and the ratio of the diffusion coefficients will destabilize the constant steady states and lead to the complex spatiotemporal behaviors, including homogeneous and inhomogeneous periodic solutions and nonconstant steady states. Moreover, the numerical simulations coincide with our theoretical results.

Global Bifurcation Analysis of Higher Codimension in a Ratio Dependent Predator-Prey Model with Prey Refuge and Constant Yield-Harvesting of Both Species

Global Bifurcation Analysis of Higher Codimension in a Ratio Dependent Predator-Prey Model with Prey Refuge and Constant Yield-Harvesting of Both Species

On the spatiotemporal structures of ratio-dependent prey–predator model of ecological system

Ecological system is the interaction of biological community with other organisms and their physical environments. One of the important models is spatiotemporal prey–predator model of Michaelis–Menten-type functional response and reaction diffusion with constant harvest rate. This paper investigates the spatiotemporal structures of ratio-dependent prey and predator densities under different constraint conditions and suitable parameters. The [Formula: see text] model expansion technique is followed to extract these densities. The prey and predator densities behave differently depending on the diffusion coefficients and other parametric ratios. The 3D and 2D behavior of these densities are also plotted and observed. These results may help for better understanding to study the biological community in a real marine environment or ecological system.

DYNAMIC STUDY OF A RATIO-DEPENDENT PREDATOR–PREY MODEL WITH STRONG ALLEE EFFECT AND NONLINEAR HARVESTING

The harvesting of species occurs in terrestrial and aquatic habitats across the world. It not only causes alteration in the population structure of the species subjected to harvesting but also of the species in interaction with the harvested species. The present work investigates the effect of nonlinear prey harvesting on the dynamics of a ratio-dependent predator–prey system with a strong Allee effect in prey population. It is found that the system exhibits a rich spectrum of dynamics including saddle-node bifurcation, Hopf bifurcation and homoclinic bifurcation with respect to the parameters that shape the nonlinear harvesting rate, namely, the maximum harvesting rate and a half-saturation constant that represents the prey density at which half of the maximum harvesting rate is reached. It is found that the basin of attraction of the stable coexistence state shrinks as the harvesting rate increases and if the harvesting rate is above a threshold value at which saddle-node bifurcation occurs, the stable coexistence of predator and prey populations is not possible for any initial start. It is also found that the harvesting policies in which the harvesting rate increases less rapidly at low prey population size are more favorable for the stable coexistence of species. The presence of Allee effect in the prey population is found to increase the chances of extinction of both species by reducing the threshold value of the harvesting rate at which the unconditional extinction occurs. Numerical simulations are carried out to support the analytical findings.

PERMANENCE OF A LOTKA-VOLTERRA RATIO-DEPENDENT PREDATOR-PREY MODEL WITH FEEDBACK CONTROLS AND PREY DIFFUSION

A three species multi-delay Lotka-Volterra ratio-dependent predator-prey model with feedback controls and prey diffusion is investigated. By developing some new analysis methods, some sufficient conditions are derived for the permanence of the system.

Dynamical behaviors of a constant prey refuge ratio-dependent prey–predator model with Allee and fear effects

In this paper, we consider a nonlinear ratio-dependent prey–predator model with constant prey refuge in the prey population. Both Allee and fear phenomena are incorporated explicitly in the growth rate of the prey population. The qualitative behaviors of the proposed model are investigated around the equilibrium points in detail. Hopf bifurcation including its direction and stability for the model is also studied. We observe that fear of predation risk can have both stabilizing and destabilizing effects and induces bubbling phenomenon in the system. It is also observed that for a fixed strength of fear, an increase in the Allee parameter makes the system unstable, whereas an increase in prey refuge drives the system toward stability. However, higher values of both the Allee and prey refuge parameters have negative impacts and the populations go to extinction. Further, we explore the variation of densities of the populations in different bi-parameter spaces, where the coexistence equilibrium point remains stable. Numerical simulations are carried out to explore the dynamical behaviors of the system with the help of MATLAB software.

Pattern formation in a ratio-dependent predator-prey model with cross diffusion

<abstract><p>This paper is focused on a ratio-dependent predator-prey model with cross-diffusion of quasilinear fractional type. By applying the theory of local bifurcation, it can be proved that there exists a positive non-constant steady state emanating from its semi-trivial solution of this problem. Further based on the spectral analysis, such bifurcating steady state is shown to be asymptotically stable when the cross diffusion rate is near some critical value. Finally, numerical simulations and ecological interpretations of our results are presented in the discussion section.</p></abstract>

Exploration on dynamics in a ratio-dependent predator-prey bioeconomic model with time delay and additional food supply.

In this manuscript, a novel ratio-dependent predator-prey bioeconomic model with time delay and additional food supply is investigated. We first change the bioeconomic model into a normal version by virtue of the differential-algebraic system theory. The local steady-state of equilibria and Hopf bifurcation could be derived by varying time delay. Later, the formulas of the direction of Hopf bifurcation and the properties of the bifurcating periodic solutions are obtained by the normal form theory and the center manifold theorem. Moreover, employing the Pontryagin's maximum principle and considering the instantaneous annual discount rate, the optimal harvesting problem of the model without time delay is analyzed. Finally, four numeric examples are carried out to verify the rationality of our analytical findings. Our analytical results show that Hopf bifurcation occurs in this model when the value of bifurcation parameter, the time delay of the maturation time of prey, crosses a critical value.

Modeling the Dynamics of a Ratio-Dependent Leslie–Gower Predator–Prey System with Strong Allee Effect

In this paper, the dynamics of a ratio-dependent predator–prey model with strong Allee effect and Holling IV functional response is investigated by using dynamical analysis. The model is shown to have complex dynamical behaviors including subcritical or supercritical Hopf bifurcation, saddle-node bifurcation, Bogdanov–Takens bifurcation of codimension-2, a nilpotent focus or cusp of codimension-2. The codimension-2 Bogdanov–Takens bifurcation point acts as an organizing center for the whole bifurcation set. The coexistence of stable and unstable positive equilibria, homoclinic cycle is also found. Our analysis shows that the ratio-dependent model may collapse suddenly due to certain parameter variation, i.e. the numbers of predator and prey will decrease sharply to zeroes after undergoing a short time of sustained oscillations with small amplitudes. Of particular interest is that the coalescence of saddle-node bifurcation point and Hopf bifurcation point may indicate the occurrence of relaxation oscillations and the critical state of extinction of predator and prey. Numerical simulations and phase portraits including one-parameter bifurcation curve and two-parameter bifurcation curves are given to illustrate the theoretical results.

Dynamical Analysis of Ratio-dependent Predator-Prey Models with Prey Refuge and Optimal Harvesting on Both Populations

In this article, we discuss a dynamical analysis of ratio-dependent response predator-prey model with prey refuge and harvesting on both populations. Harvesting on predator and prey is used because both populations are assumed to have an economic value. In this model, it is also assumed that prey has an instinct to protect themselves from the threat of predators. The conducted dynamical analysis consists of determination of equilibria, existence conditions and their stability. Analytical results show that there are two equilibria: namely predator extinction point and the coexistence point which are exist and stable under certain condition. Furthermore, Pontryagin maximum principle is used to find optimal harvesting on predator and prey. Some numerical simulations are performed to illustrate the analytical result.

Análisis cualitativo y simulaciones de un modelo depredador-presa tipo May-Holling-Tanner razón-dependiente con una fuente alternativa de alimento para el depredador

In this work, a May-Holling-Tanner ratio-dependent predator-prey model is studied with an alternative food source for the predator, described by a two-dimensional system of ordinary differential equations. We study the existence and uniqueness of the solutions of the mentioned above system. In addition, the boundedness and positivity of these solutions are analyzed and we establish conditions for the local stability of a simplified model, through a differentiable equivalence. Likewise, the Python programming language is used to perform the simulations using the Runge-Kutta numerical method of order four with the aim of showing the different cases of qualitative analysis.

Positive periodic solutions of a discrete ratio-dependent predator-prey model with impulsive effects

Positive periodic solutions of a discrete ratio-dependent predator-prey model with impulsive effects

Global Solution and Spatial Patterns for a Ratio-Dependent Predator–Prey Model with Predator-Taxis

Global Solution and Spatial Patterns for a Ratio-Dependent Predator–Prey Model with Predator-Taxis

Dynamics and bifurcations of a ratio-dependent predator-prey model

In this paper, we study a ratio-dependent predator-prey model with modied Holling-Tanner formalism, by using dynamical techniques and numerical continuation algorithms implemented in Matcont. We determine codim-1 and 2 bifurcation points and their corresponding normal form coecients. We also compute a curve of limit cycles of the system emanating from a Hopf point.

Basins of attraction in a modified ratio-dependent predator-prey model with prey refugee

<abstract><p>In this paper, we analyze a modified ratio-dependent predator-prey model with a strong Allee effect and linear prey refugee. The model exhibits rich dynamics with the existence of separatrices in the phase plane in-between basins of attraction associated with oscillation, coexistence, and extinction of the interacting populations. We prove that if the initial values are positive, all solutions are bounded and stay in the interior of the first quadrant. We show that the system undergoes several bifurcations such as transcritical, saddle-node, Hopf, and Bogdanov-Takens bifurcations. Consequently, a homoclinic bifurcation curve exists generating an unstable periodic orbit. Moreover, we find that the Bogdanov-Takens bifurcation acts as an organizing center for the scenario of surviving or extinction of both interacting species. Topologically different phase portraits with all possible trajectories and equilibria are depicted illustrating the behavior of the system.</p></abstract>

Analysis of Asymptotic and Transient Behaviors of Stochastic Ratio-Dependent Predator–Prey Model

In this paper, we focus on the asymptotic and transient dynamics of the studied ecosystem and measure the response to perturbation of the stochastic ratio-dependent predator–prey model. The method we use is mainly based on the Kronecker product and numerical simulation. Firstly, the mean-square stability matrix can be calculated from the Kronecker product, so as to compute three indicators (root-mean-square resilience, root-mean-square reactivity and root-mean-square amplification envelope) of the response to perturbation for the studied ecosystem. Since the above-measured amounts cannot be obtained explicitly, we use numerical simulation to draw the changing figures within the appropriate parameter range. Then we obtain some conclusions by comparing the numerical results. When perturbing any populations, increasing the disturbance intensity will reduce the mean-square stable area of the system. Ecologists can manage the ecosystem, reduce losses and maximize benefits according to the numerical results of the root-mean-square amplification envelope.

Spatiotemporal dynamics of a delayed diffusive ratio-dependent predator–prey model with fear effect

Spatiotemporal dynamics of a delayed diffusive ratio-dependent predator–prey model with fear effect

Complex Dynamics of a Ratio-Dependent Predator-Prey Model Induced by Spatial Motion

One of the most efficient predator-prey models with spatial effects is the one with ratio-dependent functional response. However, there is a need to further explore the effects of spatial motion on the dynamic behavior of population. In this work, we study a ratio-dependent predator-prey model with diffusion terms. The aim of this work is to investigate the changes in predator’s distribution in space as the prey populations change their mobility. We observe that the frequency diffusion of the prey gives rise to the sparse density of the predator. Moreover, we also observe that the increasing rate of the conversion into predator biomass induces pattern transitions of the predator. Specifically speaking, Turing pattern of the predator populations goes gradually from a spotted pattern to a black-eye pattern, with the intermediate state being the mixture of spot and stripe pattern. The simulation results and analysis of this work illustrate that the diffusion rate and the real intrinsic factor influence the persistence of the predator-prey system mutually.