In words, the prey population grows according to its per capita growth rate minus losses to predators. The equation for the prey population thus becomes The number of prey killed in one time interval will be the product of these, or using the symbols given above, aC t V t. Finally, it will depend on the attack rate: the ability of a predator to find and consume prey. It will also depend on the number of prey available: the more prey, the more successful the predators. This number killed will depend on the number of predators: the more predators, the more prey they will kill. To model the prey population, we begin with a basic geometric model for the prey populationĪnd subtract the number of prey individuals killed by predators in the interval from t to t + 1. However, either or both may have an implicit carrying capacity imposed by the interaction between the two populations. In the classic Lotka-Volterra model, neither prey population nor predator population has an explicit carrying capacity. The Classical Lotka-Volterra Predator-Prey Model In this chapter, we will explore the classic Lotka-Volterra predator-prey model (Rosenzweig and MacArthur 1963), which treats each population as if it were growing exponentially. Understand how variation in prey demographic rates, predator demographic rates, and predator attack rates influence the population growth of predators and their prey.
Develop a model for the interactions between predators and their prey.
Spreadsheet exercises in ecology and evolution. This material in this chapter has been adapted from Donovan and Welden (2002).ĭonovan, T.