San Antonio Bay

 

Description


San Antonio Bay – Bahía de San Antonio in Spanish – is a coastal marine protected area in the northwest corner of San Matías Gulf, in the northern part of Patagonia, Argentina. Xerophytic (desert tolerant) shrub vegetation called "monte" thrives in the uplands of this semi-desert part of Río Negro Province.

Tidal Feast
High tidal ranges of 9.3-meters (30.5 feet) are the dominant feature of the coast. The tides are an ecological engine that exposes vast intertidal habitats perfect for shorebirds twice every day. At low tide, the water can withdraw as far as 7 km (4.3 miles) from the coastal dunes, uncovering rich feeding areas used by shorebirds:

  • Salt marshes and wide mudflats (with or without crabs) in the Bay itself;
  • Broad sand flats in the mouth of the channel connecting San Antonio Bay to San Matías Gulf (Banco Reparo and Banco Lobos);
  • Broad rocky surfaces, known as "restinga", along the Gulf shore, which are covered with small mussels that shorebirds favour (Los Alamos and El Oasis). The particular type of restinga found at San Antonio occurs at few other places on the coast of Argentina, emphasizing the special importance of the area.
  • Sand beaches. (See Map and Pictures)
The richness and diversity of feeding and resting areas make San Antonio Bay a key migratory stopover for northbound and southbound shorebirds. An estimated 25-50% of the hemisphere’s Red Knots Calidris canutus rufa that winter in Tierra del Fuego stop here on their northward flight to their breeding grounds.

Two-banded Plover (Charadrius falklandicus) and American Oystercatcher (Haematopus palliatus) breed here. Other seabirds and waterfowl also nest in this area, including South American Tern (Sterna hirundinacea) and Kelp Gull (Larus dominicanus). Endemic landbirds such as Sandy Gallito (Teledromas fuscus) and Yellow Cardinal (Gubernatrix cristata) make use of adjacent uplands. San Antonio Bay is an important nursery for mollusks and fishes, some of them of high commercial value.

Popular for People and Wildlife
At San Antonio, rainfall averages 310 mm (12.2 in) a year; mean annual air temperature is 11.7º C (53º F). In early October, shorebirds arriving from the Arctic share the landscape with Southern Right Whales. In March, during peak shorebird migration, the climate is quite mild, with daily high temperatures around 26º C (79º F) and lows around 13º C (55º F). Tourists also find San Antonio very agreeable at this time of year, and it has become a destination for beachgoers and nature lovers who appreciate the richness of sea life: dolphins and Sea Lions, spectacular flocks of shorebirds swooping over the flats at low tide, and hundreds of colored Burrowing Parrots Cyanoliseus patagonus flying over the town and cliffs where they nest. They call San Antonio the "bluest gulf of the continent" because of the deep blue color of the sky and the sea.
Site Facts

Country, State,
Province/Region:
Argentina,
Province of Río Negro

Relative Location:
Northern Patagonia, from the Baliza San Matías (to the east) to El Sótano, including about 45 km of beaches.

Latitude/Longitude:
40º 45’ S, 64º 55’ W

Category:
International Site

Basis for Designation:
More than 100,000 shorebirds per year, including 40,000 Red Knots (Calidris canutus,) (around 25% of the biogeographic population). In recent years, fewer knots have been observed in the area, reflecting the dramatic declines that have been recorded for the species: it is estimated that at least 50% of the rufa population uses the area, underlining its importance for the future conservation of the species.

Size:
16,900 ha. (41,761 acres)

Joined:
1993

Site Owner/Steward:
Province of Río Negro

Site Partners:
Fundación Inalafquen, Consejo Provincial de Ecología de la Provincia de Río Negro

Contact:
Oscar Echeverría
CODEMA President
Province of Río Negro
oecheverria@codema.rionegro.gov.ar

Mabel Leonardo
President of Concejo Deliberante de San Antonio Oeste
celus05@hotmail.com

Patricia González
Fundación Inalafquen
ccanutus@yahoo.com.ar