Coastal-Marine MPA
Rincón de Ajó
Defined Purpose Nature Reserve and Comprehensive Nature Reserve


The Rincón de Ajó Reserve is composed of two areas, the Integral Natural Reserve (coastal) and the Natural Reserve of Defined Objectives (marine). This reserve is part of the system of natural areas of Samborombón Bay, which is an extensive intertidal zone, consisting mainly of marshes, brackish marshes and crab beds. It is home to wetlands of great importance for biodiversity, particularly for a large number of migratory bird species.

The Natural Reserve (coastal sector) maintains its original natural characteristics, thanks to the fact that it is not very suitable for agricultural activity. It includes a complex system of brackish marshes and mudflats shaped by tidal action. The pampas deer, a natural monument of the Province, is one of its most relevant inhabitants, as well as a great variety of birds. The Reserva Natural de Objetivos Definidos (marine sector) contains a great diversity of marine fauna that finds in this site an ideal place for reproduction and is the starting point for important regulated economic activities.

Geographic Location


Buenos Aires


-36.32° Latitude S

-56.94° Longitude W

Size and Limits

Total Area:


Marine Area (RNOD):


Continental Area (RNI):


Area estimated based on the calculation of the area of the polygon represented on the map (ArcGIS PRO) with an Albers Equivalent Conic projection to preserve area calculations.

OPDS Bs. As. reports 95 km2 for the Reserva Natural de Objetivos Definidos (RNOD) and 28.67 km2 for the Reserva Natural Integral (RNI) (Read More).

Legal Aspects



Year of Creation


Creation Legislation

Provincial Law 12016 The law creates the Comprehensive Nature Reserve and, as a complement, creates the Defined Purpose Nature Reserve

IUCN Management Category

Marine Area (Defined Purpose Nature Reserve):


Continental Area (Comprehensive Nature Reserve):


Eco-regions represented


Argentine Province
Río de la Plata Ecoregion


Pampa Ecoregion

Conservation Objectives

This reserve still maintains its original natural characteristics, as it is not suitable for farming. It includes a complex system of brackish swamps and marshes created by low tides. The Pampas Deer, an emblem of the province, is one of the most important species, as well as a great variety of birds.

Rincón de Ajó shelters a large diversity of marine fauna as it is an ideal site for reproduction, and it is also an area for important regulated economic activities. This reserve consists of two areas with different management categories. Conservation of the representative area of swamps, crab fields, marshlands and grasslands that are the refuge of endemic fauna species.

Conservation values

1. Coastal Mixoalino wetland.
2. Pampean grasslands
3. Talares
4. Pampas deer
5. Migratory birds

Colonias y sitios de parada

La siguiente tabla presenta las colonias o sitios de parada de algunas especies emblemáticas de aves y mamíferos marinos presentes dentro de los límites del AMP.


Year of Management Plan approval


Management effectiveness and evaluation year

Not evaluated

Sources consulted: Management Plan (2017).
Seabird colonies: See Bibliography.