One of the effects of the farmer's action on the ecosystem would be that the birds will consume beneficial insects along with the pest species.
Biological control of pest requires that a living organism that will prey on the pests are introduced into the ecosystem
However, the most effective biological control of pests has to do with introducing biological agents that are very specific in action.
Using a bird species to control insect pests may lead to beneficial insects being consumed along with the insect pest in the ecosystem. The loss of beneficial insects will create a new problem in the ecosystem.
More on biological control of pests can be found here: https://brainly.com/question/1374168
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