Question

An introduced insect is devastating several related plant species within a diverse natural area. An environmental manager is tasked with developing and preserving the area. He decides to use a biological control method, a parasitic fly that feeds on the pest insect's larvae. Would this be considered a density-dependent or a density-independent approach to population control?

A. Density-independent, because it is not likely to completely control the pest's density

B. Density-independent, because both pest and biological control agent are introduced

C. Density-independent, because the parasite could become a pest, causing a natural disaster

D. Density-dependent, because it reduces the population density of the pest

E. Density-dependent, because both pest and biological control agent are introduced

Answer 1

The correct answer is D. I previously gave a wrong answer. I have given the correct answer with explanation. Hope this helps you.

In density dependant population regulation the population growth rates are regulated by bringing about changes in the population density. In the given scenario, biotic agent is used to regulate a population. Here the agent is the fly which is a predator to the insect.

A will not be the answer as the number of the pest population is decreasing.

B is not the answer as the pest population was already present, so the option does not make any sense.

C is not the answer as the parasitic fly predates on the insect not on the plant species.

E is not the answer as the pest was already present.