Araguaia National Park: Bananal Island (Brazil)
Araguaia National Park is located on Bananal Island in the Brazilian state of Tocantins. It is the largest known river island on Earth. The northern one-third of the island, which is designated as a National Park, is a popular destination for ecotourism. The southern two-thirds are indigenous territories.
Araguaia National Park
Araguaia National Park, originally established in 1959, is located on Bananal Island (Ilha do Bananal) in the western part of the Brazilian state of Tocantins. In 1986, most of the river island was declared indigenous land. The northern one-third of the island, which is designated as a National Park, is a popular destination for ecotourism. The southern two-thirds are indigenous territories.
The entirety of Bananal Island is either a natural or cultural preserve:
- Araguaia National Park covers an area of 557,700 ha or 5,577 sq km (1,377,920 acres or 2,153 sq mi).
- A further 1,258,500 ha or 13,585 sq km (3,356,921 acres or 5,245 sq mi) is a cultural preserve for indigenous peoples.
Araguaia National Park is largely flat land and lies at an altitude of 200 - 240 m (656 - 787 ft) above sea level. It is situated at the junction of the Amazon biome to the north and the grassland and stunted woodland biome to the south.
Rainfall is most frequent between November and March. The river is subject to large fluctuations in level and the park is subject to periodic flooding.
Flora
The landscape is a blend of Pantanal wetlands, Cerrado savanna and Amazonian Rainforest. The flora consists of a mixture of savannah grassland, scrub and deciduous forest. In addition, there are piassava palms and buriti palms in parts of the park that are frequently inundated.
In the forested areas, some frequently encountered species include the cow tree, Cabralea, Tabebuia, Qualea parviflora, black sweetwood and genipap. In the drier savannah part of the park, there are many species of grasses, with scattered trees such as the souari nut tree and the pau-d'alho.
Fauna
Mammals in Araguaia National Park include marsh deer, other species of deer, peccary, capybara, giant anteater, maned wolf, jaguar, giant otter and armadillo.
Reptiles present include the anaconda, spectacled caiman, black caiman and South American river turtle. The rivers are home to freshwater fish as well as Amazon river dolphins and Tucuxi dolphins.
The avifauna includes the common toucan, anhinga, greater rhea, quail, partridge, osprey, Orinoco goose, heron, egret, Spix's macaw, hoatzin and musician wren.

Location map of Bananal Island in the Brazilian state of Tocantins
Bananal Island
Bananal Island is a large river island formed from the bisection of the Araguaia River, in the southwestern part of the Brazilian state of Tocantins. The island is formed by a fork in a very flat section of the river. It is the largest fluvial island in the world.
The island was discovered on July 26, 1773, by the Sertanista (backwoodsman) José Pinto Fonseca and was initially named "Sant'Ana Island." Later, it was renamed "Bananal" due to the existence of extensive banana plantations.
Bananal is the second largest river island in the world and the largest without an ocean coastline, at 350 km (220 mi) long and 55 km (34 mi) wide. The rivers within the island flow parallel to the Araguaia and the Jaburu do Bananal is the longest river within a river.
No bridges serve Bananal Island. For much of the year, access to the island is by boat. However, for a few weeks during the dry season, from June to August, the river is low enough that the island can be reached by vehicle. The main forms of transport within the island are by horse and bicycle, or by foot.
Today, the island is a natural and cultural preserve. The northern one-third is designated as a National Park and is the habitat of babassu palms, tropical birds and freshwater fish. The southern two-thirds is set as a cultural preserve for indigenous peoples.
Suyá indigenous people populate the island and makeup at least four tribes that include the Javaés, Karajá, Ava-Canoeiro and Tuxá who live within 16 aldeias or villages.
Inside the "Mata do Mamão", an immense forest located in the north-central part of the island, there is a small group of Avá-Canoeiros who reject any kind of contact with civilization, including the indigenous peoples of the nearest villages.