The reserve is in the municipality of Silva Jardim, Rio de Janeiro. The terrain is relatively flat, with elevations from 14 to 205 metres (46 to 673 ft).[2] Average annual rainfall is 2,400 millimetres (94 in).
Temperatures range from 18 to 35 °C (64 to 95 °F) with an average of 23 °C (73 °F). The São João River defines the boundary of the reserve, which is laced with small springs, channels and streams.[2]
Environment
The vegetation includes dense lowland rainforest, some flooded and some not. Some areas have suffered deforestation. Over 365 plant species have been recorded, of which 12 are on the IUCN list of endangered species.[2]
The reserve is home to 77 known species of mammals. Currently, the mammal population is threatened due to many reasons such as wildfires and poaching.[3]
The reserve is famous for its golden lion tamarins (Leontopithecus rosalia), which represent most part of the few remaining wild golden lion tamarins in the world. There is estimated to be 1000 tamarins in the reserve and surrounding areas. Currently the Golden Lion Tamarin Conservation Project (GLTCP) is attempting to save the golden lion tamarins from extinction.[4]
The Biological Reserve is a "strict nature reserve" under IUCN protected area category Ia. The purpose is to fully preserve the biota and other natural attributes without direct human interference.
As well as protecting the coastal forest ecosystem and remaining native fauna and preserving endangered indigenous species, the reserve has the function of creating laboratories to create and restock examples of flora and fauna.[2]