The Purus-Madeira interfluvial – an Amazon region running south to north from Rondônia state through Amazonas state – has been little studied by science. It is very high in biodiversity and has been fairly well preserved up until now, thanks mostly to low human occupation and difficulty of access.Studies indicate that more than 740 bird species occur regularly in the Madeira-Purus region representing more than 40 percent of all known Brazilian avifauna and approximately 60 percent of known Amazonian bird species. A new species, Campina’s Jay (Cyanocorax hafferi). with gaudy blue plumage, was recently recognized by science.Eleven protected areas, including a new national park, created in 2009 to ensure conservation of endemic species near the increasingly improved BR-319 highway, were meant to serve as a buffer against unrestrained development in the Purus-Madeira region.However, the Federal Attorneys Office accuses the Brazilian government of creating paper parks, without staffing or management plans. As a result, this diverse ecosystem is starting to see rapid negative change as plans to pave the BR-319 go forward, with the road offering access to illegal loggers, cattle ranchers and land grabbers invading protected areas. Earlier this year, Mongabay contributor Gustavo Faleiros and filmmaker Marcio Isensee e Sá visited the unique biodiverse Amazon forests found on the divide between the Purus and Madeira river basins, where a decades-delayed plan to improve the BR-319 highway is gaining momentum, bringing environmental transformation. This story is third in the series. IGAPÓ-AÇU RIVER, Amazonas state, Brazil – Jorge Nildo does not have kind words for himself. “I was a devil. It really was a mess,” he confesses. At age 39, this Amazonian man with the open smile, remembers his days as a hunter in the rainforests of the Igapó-Açu River, a Madeira River tributary. “We would go up the river and kill 200, 300 pacas [large rodents], caititu [peccary], deer, jaguar.” Nildo also worked as a guide to hunters who came from outside the Amazon. Born on the banks of the Igapó-Açu, he knew – and still knows – how to navigate through the submerged and trees and flooded forest at the height of the wet season, and especially how to find the high ground where animals are concentrated. For those driving north from Porto Velho along the BR-319 highway, the riparian forests of Igapó-Açu represent the last large-scale section of protected unfragmented rainforest seen before approaching Manaus, the capital of Amazonas state, which lies just 200 kilometers (125 miles) farther up the road. South of the Igapó-Açu River ferry crossing, the BR-319 saw little serious maintenance since the road’s construction in the 1970s, though upkeep has been ratcheted up in recent years. North of the ferry, the asphalt is in better condition, and access is better, so we drove north past a succession of large farms, degraded pastures and remnant forest patches. The river, the largest of the tributaries in the Purus-Madeira watersheds, impresses with its beauty. Its waters are jet black duet to the acidity of the soil, decaying leaves and regular forest flooding. The river’s name comes from the Tupi language; “igapó” means flooded forest, and “açu” means large. In 2009, almost its entire length and surrounding woodlands were turned into a protected natural area – the Igapó-Açú Sustainable Development Reserve (SDR). This Brazilian government designation allows for the controlled use of natural resources by the traditional communities that occupy the land. That means that its 397,500 hectares (1,535 square miles) – an area the equivalent to four New York Cities – was no longer available after 2009 to people who did not live there after 2009. Nildo has since left his career as a professional hunter, and is today a major conservationist in the region, and a member of the Igapó-Açú SDR Management Council. “This reserve was really made to maintain the [indigenous and traditional] culture, the way of life of those who live here,” Nildo explains.