and, umm, a lot of species, for example, in southeast asia. reporter: dragon flies help control mosquito populations and manage diseases like malaria and dengue fever. but as wetlands fannish, the dragon fly s future sun certain. according to is 201 study, over a third of wetlands have been lost since 1970, a rate three times that of forests. and if you see a sign against the wetlands saying, reclaimed. what they re doing is draining it, filling it in to build housing, and infrastructure. that s destruction.