It was created in 1986 to protect a wintering zone for migratory birds along the Lagoa dos Patos, the estuary of the Guaiba river or Guaíba Lake about 200 kilometres (120 mi) south of Porto Alegre.

The park was created by decree nº 93.546 of 6 November 1986, and is administered by the Chico Mendes Institute for Biodiversity Conservation.

[2] It covers parts of the municipalities of Mostardas, São José do Norte and Tavares in the state of Rio Grande do Sul.

The basic objectives are preservation of natural ecosystems of great ecological relevance and scenic beauty and enabling scientific research, environmental education, outdoor recreation and eco-tourism.

[3] Protected species in the park include cinereous harrier (Circus cinereus), Olrog's gull (Larus atlanticus), dot-winged crake (Porzana spiloptera) and royal tern (Thalasseus maximus).