The aim of this paper is to consider a non-autonomous predator-prey-like system, with a Gompertz growth law for the prey. By introducing random variations in both prey birth and predator death rates, a stochastic model for the predator-prey-like system in a random environment is proposed and investigated. The corresponding Fokker-Planck equation is solved to obtain the joint probability density...

In this paper, maximum sustainable yield policy in prey-predator system is discussed where the prey population follows logistic law of growth. Here a model is proposed involving linear prey–predator interaction and intra-specific competition among predator populations. The growth rate of the predator depends upon predation on the modelled and alternate prey. In traditional prey–predator system,...

The classical Holling type II functional response, describing the per capita predation as a function of prey density, was modified by Beddington and de Angelis to include interference of predators that increases with predator density and decreases the number of killed prey. In the present paper we further generalize the Beddington-de Angelis functional response, considering that all predator ac...

Though prey use a variety of information sources to assess predation risk, evolutionary cohistory with a predator could constrain information use, and nonnative prey might fail to recognize risk from a novel predator. Nonnative prey might instead use generalized risk assessment, relying on general alarm signals from injured conspecifics rather than cues from predators. I tested the influence of...

We utilized a long-term data base collected over a broad geographic range to examine predator size prey size relationships for 18 species of marine fish predators from continental shelf waters off the northeast US coast. Regression analysis was used to illustrate interspecific variation in ontogenetic patterns of prey size use, gape allometries, and ratio-based trophic niche breadths. Sizebased...

A coarse grained description of a two-dimensional prey-predator system is given in terms of a simple three-state lattice model containing two control parameters: the spreading rates of prey and predator. The properties of the model are investigated by dynamical mean-field approximations and extensive numerical simulations. It is shown that the stationary state phase diagram is divided into two ...

Ecological theory suggests that prey size should increase with predator size, but this trend may be masked by other factors affecting prey selection, such as environmental constraints or specific prey preferences of predator species. Owls are an ideal case study for exploring how predator body size affects prey selection in the presence of other factors due to the ease of analyzing their diets ...

Predators play a key role in shaping natural ecosystems, and understanding the factors that influence a predator's kill rate is central to predicting predator-prey dynamics. While prey density has a well-established effect on predation, it is increasingly apparent that predator density also can critically influence predator kill rates. The effects of both prey and predator density on the functi...

In this paper, we have proposed a study on controllability and optimal harvestingof a prey predator model and mathematical non linear formation of the equation equilibriumpoint of Routh harvest stability analysis. The problem of determining the optimal harvestpolicy is solved by invoking Pontryagin0s maximum principle dynamic optimization of theharvest policy is studied by taking the combined h...

scientists are interested in find out “how to use living resources without damaging the ecosystem at the same time?” from nineteen century because the living resources are limited. thus, the harvested rate is used as the control parameters. moreover, the study of harvested population dynamics is more realistic.    in the present paper, some predator-prey models in which two ecologically interac...