The San Antonio Bay Nature Reserve
This reserve created by the province of Rio Negro in June of 1993 includes the Bay of San Antonio, from the San Matías light house (in the zone of Port San Antonio East, 60 km from Las Grutas), to El Sotano (12 the km. west of Las Grutas), including almost 45 km of beaches.
The reserve out to sea includes the zone, up to 50 meters from the line of low tide.
The coasts of San Antonio are visited by the migratory chorlo playero in groups of hundreds of thousands, that cross every year roundtrip from Tierra del Fuego to the North Pole where they nest.
Such feat requires that they gather the necessary fuel in fat form, to reach the following station of passage some 1.000 km, 3.000 km or 5.000 km away, distance that they cross without stopping.
year from Tierra del Fuego
to the North Pole.
But they can only obtain food in the amount sufficient to collect these reserves in few key sites, the wetlands.
These wetlands contain small worms, crustaceans and mollusc, which proliferate at the right moment and allow these birds to eat and to accumulate fat in their organism (they double and even triple their own weight), which they will use like fuel for his migratory flight
The area is used by 17 species of migratory birds (sandpipers), including the Chorlo Colorado and other nine species that nest and reproduce in the Arctic Polar Circle in the Northern hemisphere and the Antarctica Dove that reproduces in the Antarctica.
food before the long trip.
The conservation of the chorlos and playeros depends on many people in many countries; "when one of the links is broken, the chain is cut". For that reason the province of Rio Negro decided
to create the natural protected area"Bay of San Antonio", later it joined the international conservation efforts soliciting the recognition as an international reserve, becoming thus a site of importance at world-wide level.
The wetlands are covered by shallow waters and constitute the most productive ecosystems of the planet. In the later years these areas have been disappearing at the rate of one hectare per minute.