Conservation of plants and animals — Science STD 8 — Question

The killing of small animals disturb the life cycle and food chain. For example if we kill snakes, rodents that are eaten by snakes will increase in number and destroy the crop at mass level. In another case if we kill frogs then the number of insects that destroy our crops and are eaten by frogs will damage the crop. In nutshell killing of any animal leads to our own harm.