A small traditional population live through fishing, hunting, small-scale agriculture and sale of forest products such as nuts.

The Guariba-Roosevelt Extractive Reserve has an area of 164,224 hectares (405,810 acres) in parts of the Mato Grosso municipalities of Colniza (75%), Aripuanã (22%) and Rondolândia (3%).

Fauna include jaguar, tapir, black caiman, ocelot, capuchin monkey, six-banded armadillo, paca, agouti and birds such as barn swallow, swallow-tailed kite, solitary tinamou and gulls.

In October 2015 state employees arrested six people in the act of illegally felling trees and processing the wood.

They seized a large tractor, 80 logs and a motorcycle, and were searching for two other vehicles used to remove forest products.

Their presence was important in protecting the indigenous tribes living beside the reserve and maintaining the biodiversity in an area where a new species on monkey had recently been discovered.

[1] Decree 59 of 13 April 2015 expanded the area of the extractive reserve to a total of about 164,224 hectares (405,810 acres), with a perimeter of 654.74 kilometres (406.84 mi).