• Both predator and prey can have a major impact on each other’s distribution and abundance.• Each can cause the other’s population to rise and fall in a fairly regular pattern.
• Notice that: – Predator abundance is always lower than prey – The peaks and troughs of the predator population occur after those of the prey population
Explanation• Numbers of prey increase due to breeding cycle or seasonal availability of food• This provides more food for the predators, and their numbers increase• More predators, cause a decrease in the number of prey due to increased hunting pressure• As prey decline, less predators survive
• The classic example is the Lynx and the snow rabbit.• The data in this example is quite clear cut because the snow hare are the main prey of the Lynx and there is no other significant predator involved
Predation is a straight-forward interspecies population interaction. Onespecies uses another as a food resource. Predators play an importantrole in controlling prey population numbers in some systems. In simplesystems, the predator-prey relationship results in coupled populationosscilations
• prey numbers increase, predator numbers increase…to a point where thepredation causes population decline in the prey item..
• This is an “idealised” relationship•In reality, most predator-prey interactions are not this clear cut becauseof complex relationships within the food web, i.e. There can be morethan one predator or prey.