Ilha Grande National Park

Location: border of Mato Grosso do Sul and Paraná states Map

 

Description

Ilha Grande National Park (Parque Nacional de Ilha Grande) is a federally protected area in Brazil, established to safeguard the unique fluvial ecosystems of the Paraná River basin. Located on the border between the states of Paraná and Mato Grosso do Sul, near the Paraguay frontier, it encompasses a vast archipelago of islands, wetlands, floodplains, and riparian zones. Covering approximately 78,875 hectares (194,900 acres) or about 760 square kilometers, the park protects one of the last undammed stretches of the upper Paraná River, serving as a critical refuge for biodiversity in a region heavily impacted by hydroelectric development and agriculture. Administered by the Chico Mendes Institute for Biodiversity Conservation (ICMBio), it was designated a Ramsar Wetland of International Importance in 2017 and is part of broader conservation corridors linking protected areas across Brazil, Paraguay, and Argentina. The park's "ghost park" moniker stems from its limited public infrastructure and access, emphasizing its role more as a strict nature reserve than a tourist destination.

 

Geography and Climate

The park is positioned at coordinates around 23°24′S 53°49′W, spanning the Paraná River from the Itaipu reservoir downstream to the confluences of the Piquiri, Amambai, and Ivaí Rivers. It includes over 180 islands and islets, such as Ilha Grande (the largest), Ilha Peruzzi, Ilha Bandeirantes (also known as Ilha Jacaré), and Ilha do Pavão, along with riverbanks, natural ponds, freshwater marshes, and floodplains. The terrain is predominantly flat to gently undulating, with elevations typically below 300 meters, featuring a dynamic mosaic of aquatic and terrestrial habitats shaped by seasonal flooding. The Paraná River, the park's central feature, is the eighth-longest river globally and creates sandbars, channels, and lagoons like Lagoa Saraiva and Lagoa Xambrê.
The climate is tropical humid, with average temperatures ranging from 20–25°C (68–77°F) annually, highs up to 35°C (95°F) in summer (December–February), and lows around 10°C (50°F) in winter (June–August). Rainfall averages 1,500–2,000 mm (59–79 inches) per year, peaking during the wet season (October–March) with monthly totals up to 200 mm (8 inches), causing extensive flooding that inundates floodplains and enriches soils. The dry season (April–September) lowers water levels, exposing beaches and facilitating navigation. This hydrological regime supports a transition between Cerrado savanna-like grasslands and seasonal semideciduous forests, with riparian zones dominated by tall grasses, reeds, and aquatic vegetation.

 

History

The region's history is intertwined with indigenous peoples, including the Guarani and Xetá, who inhabited the islands and left archaeological sites now protected within the park. European exploration and settlement intensified in the 20th century, but major changes occurred with hydroelectric projects. The park's origins trace to the former Parque Nacional das Sete Quedas, created in 1961 to protect the Guaíra Falls (Sete Quedas), once the world's largest waterfall by volume—twice that of Niagara and six times Iguaçu. In the early 1980s, the falls were submerged by the Itaipu Dam, leading to the park's dissolution and displacement of residents. Natural recovery followed, with forest cover expanding 15-fold over 30 years as fears of further damming subsided.
Ilha Grande National Park was officially established on September 30, 1997, by presidential decree to preserve the remaining biodiversity of the upper Paraná. It was designated a Ramsar site in 2017, recognizing its wetland values. Management shifted to ICMBio, with fishing regulations introduced in 2008 to cover the park and adjacent areas. Despite proposals for public use, development stalled, leaving it as a "ghost park" with minimal infrastructure, partly due to discontinued trails and unresolved land compensation issues from the Itaipu era.

 

Biodiversity

As a transition zone between Cerrado and Atlantic Forest biomes, the park harbors exceptional biodiversity, including rare and endangered species. Flora features a mix of riparian forests, floodplains, and marshlands with species like aquatic plants, tall grasses, reeds, and semideciduous trees adapted to seasonal inundation. Key vegetation includes dense forest patches and transitional savanna elements.
Fauna is diverse, with over 300 bird species, such as jabiru storks (Jabiru mycteria), black-collared hawks, blue-and-yellow macaws, herons, kingfishers, anhingas, red-necked tanagers, saffron toucanets, maroon-bellied parakeets, white-necked hawks, Brazilian tanagers, scaled antbirds, green-headed tanagers, plain parakeets, channel-billed toucans, white-bearded manakins, jaó (Crypturellus undulatus), curassow (Crax fasciolata), American spoonbill (Platalea ajaja), and jacana (Jacana jacana). Many are endemic or threatened, and the park serves as a migratory stopover.
Mammals include marsh deer (Blastocerus dichotomus, the park's symbol), capybaras, brown howler monkeys (Alouatta fusca), Southeastern four-eyed opossums (Philander frenata, Atlantic Forest endemic), jaguars (Panthera onca), pumas, giant otters (Pteronura brasiliensis), neotropical otters, South American tapirs (Tapirus terrestris), giant anteaters (Myrmecophaga tridactyla), nine-banded armadillos, Azara’s agoutis, coatis, ocelots, tayras, common marmosets, crab-eating foxes, and critically endangered southern woolly spider monkeys.
Reptiles feature yellow-throated caimans (Caiman latirostris). Aquatic life includes fish like painted catfish (Pseudoplatystoma corruscans), jaú (Paulicea luetkeni), armed catfish (Pterodoras granulosus), golden dorado (Salminus maxillosus), and pacu (Piaractus mesopotamicus), with the park acting as a vital breeding and feeding ground.

 

Conservation Efforts and Status

Classified as IUCN Category II (national park), Ilha Grande focuses on ecosystem protection and limited recreation. ICMBio oversees management, enforcing fishing regulations (since 2008) and fire control through the Manejo Integrado de Fogo program for prescribed burns. It forms part of the Santa Maria Ecological Corridor, connecting to Iguaçu National Park and the Itaipu reservoir's protected margins, and is proposed for the Trinational Biodiversity Corridor to link units across Brazil, Paraguay, and Argentina in the Upper Paraná ecoregion.
Efforts include habitat restoration, artificial nesting for parrots (addressing deforestation), and community education. As a Ramsar site, it emphasizes wetland conservation, with collaborative initiatives involving locals and NGOs to combat illegal activities. The park's establishment has buffered against farmland expansion, promoting sustainable resource use and species recovery.

 

Threats and Challenges

Key threats include fires (criminal, intentional, or accidental from nearby land clearing), illegal hunting and fishing, pollution from upstream sources and vessel oil, invasive species introduction, and habitat fragmentation from agriculture and potential hydropower. The submersion of Sete Quedas altered ecosystems, reducing macaw populations, and strong river currents pose safety risks. Encroachment and lack of infrastructure hinder enforcement, while unresolved compensation for displaced residents adds social challenges.

 

Tourism and Activities

Access is limited and free, with no entrance gates or facilities like restrooms, restaurants, or camping. The river (excluded from park boundaries) allows navigation, but island landings require ICMBio authorization, except at Praia do Meião (Prainha), a small beach 5–10 minutes from Porto Camargo. Activities include boat tours from ports like Porto Camargo (northern access, Icaraíma, PR), Altônia (continental, for Lagoa Xambrê via private property), and Guaíra (southern). Kayaking, wildlife viewing, birdwatching, swimming at beaches, and regulated sport fishing are popular. The Rota dos Pioneiros trail offers historical kayak routes. Visitors must use authorized operators, wear life jackets due to currents, and avoid drinking river water. Boat rides pass scenic islands, lagoons, and bird sanctuaries like Lagoa Saraiva (no landing).

 

Research and Scientific Importance

The park is vital for studying fluvial ecosystems, wetland dynamics, and species recovery in dam-impacted regions. It hosts archaeological sites from Guarani and Xetá cultures, supporting cultural research. As an Important Bird and Biodiversity Area (IBA), it aids avifauna monitoring, though data gaps exist. Hydrological studies focus on fish breeding, while conservation research informs corridor initiatives and fire management.

 

Notable Events and Recent Updates

As of August 2025, no major incidents like large fires or developments are reported, but ongoing efforts include enhanced fire monitoring and potential tourism expansion. The 2017 Ramsar designation boosted international recognition, while historical events like the 1980s Itaipu flooding remain pivotal. Proposals for reforestation and sustainable tourism persist, with the park's recovery highlighting natural resilience.