The Mbaracaya Forest Nature Reserve (MFNR) consists of 64,405.7 hectares, located in the eastern region of Paraguay near the Brazilian border, an area with small landholdings and numerous cattle rancHng establishments in the Mbaracaya Range (Karapa). In the east there are various properties, ranches and two indigenous communities of different ethnic partialities, and in the south and east, there are farms of varying sizes.
Mbaracaya is located within the humid subtropical forest of eastern Paraguay, part of the Interior Atlantic Forest of southeastern Brazil, northeastern Argentina and eastern Paraguay. It is the largest continuous remnant of the IAF in Paraguay. The annual average temperature is between 21'C to 22°C, and the total annual precipitation is 1,800 mm. The Mbaracaya Range runs northeast/southeast, crossing the northeastern corner of the Reserve. This area is composed of numerous small, but deep, valleys with recurrent waterfalls creating hundreds of small tributaries towards the Jejui River basin.
Different forest types cover almost 88% of the Reserve and the remainder consists of wetlands, pasture lands, lagoons, rivers and Cerrado vegetation. The forest is divided in three different types: tall, medium and low. The tall forest generally has a significant amount of humidity, with few areas containing little or no amount of water. Many tall canopy trees are good quality lumber and can measure up to 30-35 meters. The low forests vary; some are quite far from the watercourses while others are periodically or almost permanently flooded. The Riparian forest borders the Jejui-mi River and is susceptible to periodic floods that can be very severe after days of intense rain.