Reserva natural Lagunas de San Vicente, Nature reserve in San Vicente Partido, Argentina.

Reserva natural Lagunas de San Vicente is a protected wetland area in San Vicente Partido, Buenos Aires Province, within the Matanza-Riachuelo basin. It contains the Laguna de San Vicente, the San Vicente Stream and the Laguna La Bellaca, forming a wetland complex that provides ecosystem services to the local population and the watershed. Over 200 animal species have been recorded there.

The protected area was established in 2011 through Provincial Decree to safeguard the local ecosystems. This official designation marked an important moment in preserving the wetlands and the species that depend on them.

The reserve's name comes from the Laguna de San Vicente, the largest of its water bodies, and the wetland complex is shared with the Matanza-Riachuelo basin. More than 200 animal species have been recorded here, among them chiflones, jacanas, cuervillos de cañada, teros, horneros and seven-colored tanagers, plus lagoon turtles and coipos. In 2019, carnival celebrations held around the reserve sparked controversy among local residents.

The reserve lies in the Matanza-Riachuelo basin within San Vicente Partido, south of Buenos Aires. Access is by road from San Vicente, and the wetlands can be explored on foot along the shores of the Laguna de San Vicente, the San Vicente Stream and the Laguna La Bellaca. Water levels and muddy ground vary with rainfall, so footwear suited to wet terrain helps.

The wetland naturally filters water for the Matanza-Riachuelo watershed, providing essential services to the local population. This natural cleaning function often goes unnoticed but is crucial for the region's environmental health.