Suppose that rabbits are the only prey and food supply of foxes, and that the pr

Question

Suppose that rabbits are the only prey and food supply of foxes, and that the predatorprey interaction follows LotkaVolterra dynamics. The mortality rate of foxes in the absence of rabbits is 0.1 per week, and the intrinsic growth rate of rabbits in the absence of predation is 0.2 per week. The capture efficiency is 0.002, and the efficiency at which rabbit biomass is converted into fox biomass is 0.2. If there are 40 foxes in a population, and 350 rabbits are present, the rate at which prey will be killed is _______ per week.

28

70

42

24

28

70

42

24

Explanation / Answer

Answer: (c) 42

Explanation:

For prey populations (N), assume growth is exponential, with mortality due to predation associated with the density of both prey and predator (P) populations and the efficiency of turning an encounter into a successful meal (a)

dN/dt = rN - aNP

Addition or loss of individuals in a prey population (dN/dt) is equal to the intrinsic growth rate (r) times the population size (N), minus the predation rate, which is equal to an estimate of the encounter rate (NP) times a coefficient that expresses the capture efficiency of the predator (a)

(0.2 x 350) - (0.002 x 350 x 40) = 70 - 28 = 42

Related Questions

Navigate

• Browse (All)
• Browse S
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.