# Prey Predator Dynamics

Topics: Predation, Ecology, Lotka–Volterra equation Pages: 2 (483 words) Published: April 1, 2013
NISHANT PRAVEEN          ASSIGNMENT 3                                                                                                             1111035 EFFECT OF PREY PREDATOR RELATIONSHIP OVER POPULATION DENSITY Study of species interaction has always interested ecologist. These studies help to develop the food web or chain where we see very simplified picture of interaction of species specifically about Prey and predation relationship .Prey predator relationship has been widely studied in ecology. An important general relation between prey and predator population was given by LOTKA-VOLERRA EQN. Which is a first-order non linear differential eqn given as:

1.dx/dt=x(A-By)

and 2. dy/dt=-y(C-Dx)

Where x the prey population increses proportionaly to population at any point of time and decreases proportionaly to its population multiplied by predators. And y the predator population decreses proportionaly to its population and increses proportionaly to its population multiplied by population of prey. The graphical solution to these differential equations follow:

so an increase in prey population later shows as an increase in predators and vice versa.

But this is a general model and more insight into prey predator dynamics have been observed like an article by Helen.J.Edwards and co authors who studied prey population dynamics for these type of interactions:1)Prey may compete for resources in a single habitat, or may be segregated, thus competing only indirectly . 2)Models in which a single prey species moves between two populations in different habitats have also been studied. A special feature of this type of relationship is that the rate at which a prey individual is attacked by a predator decreases when the population of that species becomes rare compared with the population of another prey .This may be because of several reasons:-: 1.)When one prey type becomes rare the predator may shift to more abundant specie. 2.)The decrese in prey population...