Consider this food web. It is rich with animal species that fill a variety with niches within the ecosystem. Imagine that a local farmer has sprayed the area with insecticide. Predict how this might "initially" impact the food web and the roles each organism plays within it.
a
Although the farmer's spray would wipe out the insects, the other herbivores, rabbits, squirrels, mice and birds, would take over the empty niches and the food web would continue with very little change.
b
One section of the food web would be greatly impacted: the section containing the hawk and snake. They would quickly disappear due to the pesticide use.
c
One section of the food web would be greatly impacted right away: the section containing the insects and insect-eating animals. Without insects and possibly spiders, there would be no food for the frogs, shrews and insectivorous birds.
d
The entire food web would be decimated. The food web would collapse without this niche being filled due to the pesticides used.
c
One section of the food web would be greatly impacted right away: the section containing the insects and insect-eating animals. Without insects and possibly spiders, there would be no food for the frogs, shrews, and insectivorous birds.