Trophic Interactions and Predator-Prey Dynamics

This set of flashcards covers key vocabulary and concepts related to trophic interactions, predator-prey dynamics, and their mathematical modeling.

Predator-prey cycles

Fluctuations in the populations of predator and prey species over time, often exhibiting synchronous oscillations.

Lotka-Volterra model

Mathematical model that describes the dynamics of biological systems in which two species interact, one as a predator and the other as prey.

Functional response

The relationship between the density of prey and the feeding rate of predators, often categorized into types I, II, and III.

Numerical response

The change in the abundance of predators in response to changes in the abundance of prey.

Exponential growth rate

The rate at which a population expands when resources are unlimited and conditions favor growth.

Prey adaptations

Physical or behavioral traits that enhance an organism's ability to avoid predation.

Predator adaptations

Traits that enhance a predator's ability to capture and consume prey.

Isoclines

Lines on a phase-plane diagram that represent combinations of predator and prey populations where growth rates are zero.

Phase-plane diagram

A graphical representation that depicts the dynamics of two interacting populations, such as predator and prey.

Biocontrol

The use of natural predators or parasites to control pest populations.

r/p = P

Zero prey Population growth

r/p > P

Prey Population growth increase

r/c < P

Prey population decreasing

N = m/ac

Predator population has zero growth

N > m/ac

Predator population increases

N < m/ac

Predator population decreases

Relationship between predator and prey populations and their time period differences

Predatory and prey populations are ¼ out sync

R and M increases

Cycles are shorter and faster

Predicted population dynamics

Cycles of predators and prey have same period but with a phase shift the amplitude and period depend on initial conditions N, P, m, r, c, a

Lotka voltera model assumptions

Prey limited by predation, predators can only persist when prey are present, individual predators can consume infinite prey, random interactions and no density dependence.

Huffaker experiment findings

added habitat complexity adding more refuge

Type 1 functional response

Prey consumption increases linearly with prey density. feeding rate = cN often unrealistic, ignores other limits to predator feeding rate.

Type 2 Functional response

Prey consumption plateaus as prey density increases, incorporation of handling time, maximum possible feeding rate, = 1/h at which predator is satiated

Type 3 function response

S shaped relationship shown by generalist predators, feeding initially low increasing with prey density, change diet to more abundant prey, feeding rate increases at higher densities and plateaus at 1/h