Answer: Because they cause a disturbed ecosystems.
Explanation: It is evident that the military base provided both survival and elimination platforms for the butterflies species, translating that the butterflies are living in a disturbed ecosystem.
Hence, this provides a good template to understudy conservation for the purpose of maintaining and making wise-use of important wildlife resources and most importantly, the endangered species. Butterflies species dynamics had been used as an important tool for conservation for years now.