The conservation unit was originally created in 1961 as the Jaru Forest Reserve, then replaced in 1984 by the Jaru Biological Reserve. The initial area of was increased by about on 2 May 2006. The reserve now covers . It is administered by the
Chico Mendes Institute for Biodiversity Conservation. It is located in the municipalities of
Vale do Anari,
Machadinho d'Oeste and
Ji-Paraná in the state of Rondônia. The reserve would be in the proposed
South Amazon Ecotones Ecological Corridor. Altitudes range from . Average annual rainfall is . Temperatures range from with an average of . The reserve is in the middle
Ji-Paraná River basin, in the sub-basin of the Tarumã stream. It lies between the Sierra do Moquém to the north and the Sierra da Providência to the south, south east and east. A survey recorded 168 species of fish, the probable presence of 189 species of amphibians and reptiles, 538 species of birds and over 73 species of mammals. ==Conservation==