Carijós

Carijós Ecological Station is a federal protected area encompassing the largest remaining mangrove complex in Santa Catarina state, southern Brazil. Located in the northern coastal municipalities of Florianópolis Island — primarily Canasvieiras and Ratones — the station covers approximately 7,110 hectares, protecting estuaries, restinga shrublands, Atlantic Forest fragments, and extensive tidal mangroves. Established to preserve the ecological functions of the Ratones and Saco Grande river estuaries, Carijós is managed by ICMBio and represents one of the southernmost significant mangrove ecosystems on the Brazilian Atlantic coast. The reserve is closed to public entry but surrounds the urban fringe of Florianópolis.

Carijós supports exceptional aquatic and coastal biodiversity. The mangrove channels are vital nursery grounds for fish species commercially harvested off Santa Catarina's coast, including snook, mullet, and sea bass. Neotropical otters hunt in the tidal creeks and are frequently observed near mangrove margins. The American black-necked stilt, roseate spoonbill, and various egret and heron species use the mudflats as feeding grounds year-round. The South American coati and crab-eating raccoon forage in mangrove margins at low tide. Bottlenose dolphins occasionally enter the Saco Grande estuary, and the reserve's wetlands host internationally significant populations of migratory shorebirds during the austral summer stopover season.

The station's dominant vegetation is mangrove forest, composed primarily of red mangrove (Rhizophora mangle), white mangrove (Laguncularia racemosa), and black mangrove (Avicennia germinans). These form dense, root-tangled intertidal forests reaching 8–12 meters in height along sheltered estuarine channels. Restinga — coastal shrubland on sandy soils — forms transition zones between tidal areas and terra firma, supporting endemic bromeliads and orchids adapted to sandy, nutrient-poor conditions. Atlantic Forest fragments in the reserve's upland sectors contain characteristic species of the Mixed Ombrophilous Forest subtype. Aquatic macrophytes colonize freshwater reaches above tidal influence, and exotic Hedychium coronarium invades disturbed margins.

Carijós sits on the northern coastal plain of Santa Catarina Island and adjacent mainland, where Precambrian granitic basement rocks are overlain by Quaternary sediments. Holocene marine transgression deposited the sandy barrier beaches and restinga substrates, while river-borne sediments have built the estuarine mudflats that support mangrove colonization. The Ratones River drains a small catchment in the island's hilly interior and delivers fine silts and organic material to the estuary. Tidal range in the area is microtidal (averaging 0.5–0.8 m), which favors the development of stable, well-vegetated mangrove stands rather than the more dynamic systems found in macrotidal environments along Brazil's northern coast.

The region experiences a humid subtropical climate (Köppen Cfa) with year-round rainfall averaging 1,500–1,700 mm annually and no pronounced dry season. Summers (December–February) are hot and humid, with temperatures regularly reaching 32–35°C and frequent convective thunderstorms. Winters (June–August) bring mild conditions with occasional cold fronts from the south that can push temperatures below 10°C. The Santa Catarina coast is periodically affected by extratropical cyclones and frontal systems that drive storm surge events — significant for mangrove health and shoreline stability. Sea surface temperatures in the adjacent Baía Norte range from 18°C in winter to 26°C in summer.

The name Carijós refers to the Tupinambá-related indigenous group that inhabited the Santa Catarina coast prior to Portuguese colonization in the 16th century. The Carijós fished the estuaries, harvested mangrove crabs, and maintained seasonal encampments along the bay margins. European colonization in the 17th and 18th centuries, particularly by Azorean settlers, brought fishing villages and small-scale agriculture to the island's northern coast. Mangrove wood was historically harvested for construction and charcoal production. By the 20th century, rapid urban expansion of Florianópolis began encroaching on estuarine areas, leading to calls for formal protection of the remaining mangrove complexes before further loss.

Carijós Ecological Station was established by federal decree in 1987 in response to rapid urbanization threatening Florianópolis's coastal ecosystems. The protected area incorporated two distinct estuarine complexes — Ratones and Saco Grande — that had survived development pressure due to their tidal and waterlogged terrain. ICMBio manages the station, which periodically updates its management plan to address boundary encroachment, water quality degradation from urban runoff, and mangrove die-back events. Restoration projects have replanted mangroves in areas disturbed by illegal construction and tidal channelization. The station collaborates with UFSC (Federal University of Santa Catarina) on long-term ecological monitoring programs.

Carijós does not permit general public visitation within its boundaries. The protected estuaries are accessible only to researchers and ICMBio staff holding active permits. A small visitor reception point near the Ratones River provides interpretive materials and is the base for community educational programs. Canoe and kayak observation of wildlife at the reserve boundary is practiced from community-operated launch points in Ratones village. The nearby beaches of Jurerê, Daniela, and Canasvieiras on Florianópolis Island offer coastal access adjacent to the reserve's buffer zone, where mangrove bird life is visible from public shorelines.

There are no visitor facilities within the ecological station. Florianópolis serves as the gateway city, with an international airport approximately 20 km from the northern coast and a full range of hotels, restaurants, and tourist services. The Ratones community at the reserve boundary is accessible by bus from central Florianópolis in approximately 45 minutes. Researchers requiring station access must apply to ICMBio's Santa Catarina office well in advance of fieldwork. For general coastal tourism, the northern beaches of Canasvieiras, Jurerê, and Ingleses offer accommodation and water activities within a few kilometers of the protected mangroves.

Carijós faces ongoing threats from urban encroachment, wastewater discharge into estuarine channels, and illegal landfilling of mangrove margins for construction. The Ratones River catchment has experienced deforestation and urban runoff that increases sediment and nutrient loads to the estuary. Exotic species, particularly Hedychium coronarium (white ginger lily), invade freshwater margins and displace native vegetation. ICMBio has partnered with Florianópolis municipal authorities on buffer zone planning and zoning enforcement. Sea-level rise projections indicate increased tidal flooding of low-lying restinga communities over coming decades. Water quality monitoring data from the station's estuaries has informed municipal wastewater treatment upgrades in northern Florianópolis neighborhoods.