Lecture 12: Consumer-Resource Interactions

Question 1

Prey pop size (LV)

Answer 1

dN/dt = rN - cNP
exp growth minus some predator-influenced loss

Question 2

Predator pop size (LV)

Answer 2

dP/dt = acNP - mP
prey availability reduced by predator mortality rate

Question 3

What does a mean in acNP?

Answer 3

Conversion efficiency, high when single prey item valuable

Question 4

Predator functional responses

Answer 4

• Type I - predator can keep prey in check at large pop size (metensia predation on picocyanobacteria - no plateau)
• Type II - overhead plateau
• Type III - predator pressure is reduced @ lower prey population sizes

Question 5

Amphipod (predator) vs isopod

Answer 5

Adding habitat complexity shifts from type II to type III (made stronger by top predator) + reduce maximum feeding rate

Question 6

Predator numerical response

Answer 6

acN: per-capita growth rate of the predator population as a function of victim abundance

Question 7

Equilibrium solutions to the predator-prey pop growth equations and their biological interpretations

Answer 7

P = r/c
N = m/ac