Functional response

It is associated with the numerical response, which is the reproduction rate of a consumer as a function of food density.

The type II functional response is characterized by a decelerating intake rate, which follows from the assumption that the consumer is limited by its capacity to process food.

Type II functional response is often modelled by a rectangular hyperbola, for instance as by Holling's disc equation,[3] which assumes that processing of food and searching for food are mutually exclusive behaviours.

Wolves are then satiated and the total number of caribou kills reaches a plateau.

This accelerating function was originally formulated in analogy with of the kinetics of an enzyme with two binding sites for k = 2.

Holling identified this mechanism in shrews and deer mice feeding on sawflies.

The characteristic saturation point of the type III functional response was also observed in the deer mice.

Murdoch demonstrated this effect with guppy preying on tubificids and fruit flies.

When the prey densities change in approximate proportion to each other, as is the case in most natural situations, a type II functional response is typically found.

This explains why the type III functional response has been found in many experiments in which prey densities are artificially manipulated, but is rare in nature.