The Site features a range of ecosystems such as streams, rivers, swamps, wetlands and terrestrial biotopes. It boasts wide biological diversity with 148 species of mammals, which represent 2.7% of the world’s mammals. The Site hosts threatened species such as the brown-headed spider monkey (Ateles fusciceps), the giant otter (Pteronura brasiliensis), the giant anteater (Myrmecophaga tridactyla) and the critically endangered cotton-headed tamarin (Saguinus oedipus). In addition, 86 bird species have been recorded, with some of them considered endemic such as the blue-billed curassow (Crax Alberti) and the northern screamer (Chauna Chavaria), and others coming from North America, such as the little blue heron (Egretta calerua) and the laughing gull (Larus Atricilla). Also, 52 representative fish species support the livelihoods of many people who live inside and around the Site. Among the main threats to the Site are land use changes, forest felling, water pollution resulting from informal gold mining, and the use of pesticides in the agricultural areas of the wetland.