Laguna de Rocha, located in the department of Rocha, is a vast lagoon of extraordinary beauty, placid waters and varied landscapes. The water body itself covers 7,200 hectares, with a mean depth of 0,58 metres. Its main tributaries are Arroyo Rocha, Arroyo Las Conchas, Las Palmas and Arroyo Noques. A narrow sandbar divides it from the Atlantic Ocean, which opens three or four times per year, naturally or artificially. This exchange of fresh and salt waters enables an abundant and varied biodiversity.
Importance for conservation
It has been widely recognised at the national and international level as a relevant area for conservation. It was designated as a Ramsar site in 2015, and BirdLife International recognises it as an IBA (Important Bird and Biodiversity Area) under number UY019. It is also part of the Bañados del Este Biosphere Reserve of the MAB (Man and the Biosphere) UNESCO programme, and is also a Western Hemisphere Shorebird Reserve Network (WHSRN) site.
Home to more than 200 bird species, among them 6% of the global population of Buff-breasted Sandpipers (Calidris subruficollis), it is one of the most important conservation sites for this species in the world. There is also a large concentration of American golden plovers (Pluvialis dominica), and at least 20 more species of shorebirds.
Among the near threatened and vulnerable species recorded in the lagoon area are the black-and-white monjitas (Xolmis dominicana), Olrog’s gull (Larus atlanticus), the Chilean flamingo (Phoenicopterus chilensis). Its population of black-necked swans (Cygnus melanchoryphus) is one of the most important in the world.
Around the coast there are patches of psamophile scrub, formed by spine of the cross (Colletia paradoxa) and Peruvian pepper (Schinus molle), together with cereus, opuntia, hopseed bushes (Dodonaea viscosa), Lithraea molleoides and (Myrsine laetevirens). Various cacti are found, and also Ephedra tweediana, the only native gymnosperm shrub.
As to native mammals, brocket deer (Mazama gouazoubira), foxes, neotropical otters (Longra longicaudis), giant otters (Pteronura brasiliensis), capybara (Hydrochoerus hydrochaeris), the wildcat Leopardus geoffroyi and tucotuco (Ctenomys pearsoni). Their distribution and population figures are unknown.
Other vulnerable species include the toad Melanophryniscus montevidensis.
