Carlos Botelho

Carlos Botelho State Park is a protected area covering approximately 37,793 hectares in the southern Vale do Ribeira region of São Paulo state, Brazil. Located in the municipalities of São Miguel Arcanjo, Capão Bonito, and Pilar do Sul, the park preserves one of the most extensive tracts of lowland and submontane Atlantic Forest remaining in São Paulo state. It forms part of the UNESCO World Heritage Atlantic Forest South-East Reserves complex and shares boundaries with the larger Intervales State Park, together creating an important Atlantic Forest wildlife corridor. The park was named after Carlos Botelho, a former São Paulo secretary of agriculture who was instrumental in early forest conservation in the state.

Carlos Botelho is renowned for harboring one of the largest and healthiest populations of woolly spider monkeys (muriquis, Brachyteles arachnoides) in the world, with several hundred individuals documented in long-term population monitoring studies. The park is a focal point for muriqui research and has been studied by Brazilian and international primatologists since the 1980s. Brown howler monkeys, black-faced lion tamarins, and tufted capuchins also inhabit the forest. Tapirs, pumas, ocelots, and giant anteaters are present. The avifauna exceeds 300 species, including the Harpy Eagle, Red-tailed Amazon, and numerous Atlantic Forest endemics. The park is an Important Bird Area.

The forest of Carlos Botelho represents lowland and submontane dense ombrophilous Atlantic Forest in exceptional condition, with a closed canopy reaching 25–35 meters and a complex stratified structure including emergent trees, subcanopy, shrub layer, and dense herbaceous layer. The flora is extraordinarily diverse, with hundreds of tree species per hectare, and exceptionally rich communities of epiphytic orchids (over 200 species), bromeliads, ferns, and mosses. Palms including Euterpe edulis (juçara palm) are abundant and support frugivorous wildlife. The park also contains patches of restinga forest at lower elevations near the Ribeira valley. The floristic composition is characteristic of the interior Atlantic Forest with significant regional endemism.

Carlos Botelho occupies part of the southern extension of the Serra de Paranapiacaba, a mountain range forming the drainage divide between the coastal Ribeira River system and the Paranapanema River draining to the Paraná basin. The underlying geology is composed of Precambrian metamorphic and igneous rocks—primarily gneisses, schists, and granitoids—of the Ribeira Belt, formed during the Brasiliano orogeny approximately 600–700 million years ago. The terrain is dissected by numerous streams and rivers draining into the Ribeira de Iguape River, which flows to the sea through one of the largest estuaries in the South Atlantic. The deeply weathered tropical soils support the extraordinarily productive rainforest vegetation.

The park experiences a humid subtropical climate with warm, wet summers and cooler, less rainy winters, though rainfall occurs in all months. Annual precipitation ranges from 1,400 to 1,800 mm, with the peak rainfall from November to March associated with the South Atlantic Convergence Zone. Mean temperatures range from 17°C in the coolest months to 25°C in summer at lower elevations, with highland areas remaining cooler. The high moisture content of the atmosphere supports the dense epiphyte communities that are characteristic of the Atlantic Forest in this region. Occasional cold fronts from the south bring brief temperature drops but frost is rare at the elevations occupied by the park.

The Vale do Ribeira region was inhabited by Tupinambá coastal groups and interior Jê-speaking peoples at the time of Portuguese contact. The Ribeira de Iguape River corridor became one of the first colonial agricultural zones in São Paulo state, producing gold, rice, and later bananas. The rugged interior of the Serra de Paranapiacaba remained largely inaccessible to colonists and provided refuge for indigenous peoples displaced from the coast. The region was settled by a mix of Portuguese colonists, freed enslaved Africans who established quilombola communities, and indigenous remnant groups—making the Vale do Ribeira one of the most culturally diverse regions in São Paulo state, with recognized quilombola territories adjacent to the park.

Carlos Botelho State Park was established in 1982 through the merger of several forest reserves maintained by the São Paulo state government since the early 20th century, including the São Miguel Arcanjo Forest Reserve established in 1941. The creation of the park formalized protection of forests that had been managed as state reserves for decades, providing stronger legal protection and a management framework. Scientific interest in the park intensified following the discovery of its exceptional muriqui population in the early 1980s, which catalyzed long-term research programs. The park was included in the São Paulo Atlantic Forest Corridor Project and later incorporated into the UNESCO World Heritage inscription in 1999.

Carlos Botelho offers several trail circuits through undisturbed Atlantic Forest, making it an outstanding destination for birdwatching and wildlife observation. The Trilha do Corisco (Lightning Trail) is a moderately challenging circuit through tall lowland forest with excellent opportunities to encounter muriquis, brown howler monkeys, and forest birds. The Trilha das Bromélias (Bromeliad Trail) passes through forest sections with exceptional epiphyte diversity. The park's streams offer refreshing natural swimming pools during the warm season. The primary draw for serious wildlife enthusiasts is the chance to observe muriquis—which are habituated to researchers and guides in some areas—feeding and moving through the high forest canopy.

The park's main entrance is located near São Miguel Arcanjo, accessible via the SP-139 highway connecting Capão Bonito to the Anchieta highway (SP-150). The park operates a visitor center with interpretation materials, restroom facilities, and picnic areas near the main entrance. Camping is available in designated areas within the park. The city of Registro, approximately 60 kilometers to the south, serves as a regional hub for the Vale do Ribeira with accommodation options. São Paulo city is approximately 200 kilometers northeast via the Anchieta highway. Guided trail access is required during peak periods, and prior registration with the Fundação Florestal (managing agency) is recommended.

Carlos Botelho's most significant conservation achievement is the long-term maintenance of viable muriqui populations in highly threatened Atlantic Forest, demonstrating the value of state park protection in stemming biodiversity loss. Ongoing threats include illegal logging in adjacent private lands that reduces habitat connectivity, poaching of palm hearts (juçara palm extraction), and fire from agricultural burning in surrounding areas that occasionally enters the park during drought years. The park participates in the São Paulo Atlantic Forest Connectivity Program, which supports restoration of forest corridors between protected areas. Climate change projections for the Vale do Ribeira indicate increased drought frequency that could stress moisture-dependent epiphyte communities and alter the water balance of the forest.