Tachinid flies from Antigua have been used to control green stink bugs that attack vegetable crops in Hawaii. Why did ecologists use the flies to control the stink bugs? 

The green stink bugs attack on the vegetable crops which resulted in heavy loss in the yield of the crops. This bugs were controlled with the use of Tachinid flies. These organisms provide protection to the vegetables against the bugs. The flies were used as a form of biocontrol agent. They do not cause any environmental hazards and problems to the ecosystems like the harmful chemical pesticides.