Caíca

Habitat Distribution

• Native to Brazil; the most abundant mugilid on the Brazilian coast, ranging from the northern estuaries near the Amazon delta south through the entire Atlantic seaboard.
• Primarily a coastal and estuarine fish — bays, sounds, tidal creeks, and brackish lagoons are its core habitat, though juveniles push well into freshwater reaches of coastal rivers.
• Tolerates a wide salinity range, moving freely between full marine water and nearly fresh conditions depending on season and life stage.
• Documented in Paraíba (Cabedelo region) and throughout the Northeast; present along the Rio de Janeiro coast and south into the Prata drainage.

Key Locations

• Cabedelo, Paraíba — documented collection site and active artisanal fishery in the Northeast.
• Estuaries and bays along the Northeastern coast (Natal, João Pessoa) — shallow tidal systems with strong mullet populations.
• Coastal lagoons and river mouths of Rio de Janeiro state — consistent habitat throughout the year.
• The broader Brazilian Atlantic seaboard from the Amazon delta south — caíca is present in virtually every coastal estuary in the country.

Specific Spots

• Tidal creek mouths and estuary channels at the turn of the tide — caíca follow the current to feed on organic material stirred up by tidal flow.
• Shallow sand and mud flats inside bays; fish cruise these areas in loose schools, often visible as surface wakes or nervous water.
• Mangrove edges and brackish lagoon margins, where detritus and algae accumulate — prime feeding zones, especially on a rising tide.
• River mouths where freshwater meets salt; juveniles in particular concentrate here during warmer months.