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The Patagonian Large Marine Ecosystem is one of the largest and richest marine areas on Earth, comprising more than 2 million km², and extending from southern Brazil (23ºS) to the waters South of the Burwood Bank (55ºS) in Argentina. The high productivity of this area is sustained by the nutrient transport of two major marine currents, the Falklands-Malvinas and the Brazil currents.

The Falklands-Malvinas current derives from the Antarctic Circumpolar current, moves North along the Patagonian continental slope and contains cold (sea surface temperature less than 7ºC in the winter) and low salinity waters. On the other hand, the subtropical Brazil current contains warm (sea surface temperature about 26ºC) and high salinity waters, and moves south along the continental shelf. Both currents meet at about 38ºS in the so-called Confluence Area, which represents one of the richest marine areas in the world.

The high phytoplankton productivity of this area is the basis for its rich marine life. The PLME harbours large populations of fish, squid and crustaceans, and sustains important breeding colonies and feeding grounds of seabirds, seals and cetaceans.

Sixteen seabird species (2 species of penguins, the Southern giant petrel, 5 cormorant species, 3 seagull species, 2 tern species and 2 skua species) breed along the Patagonian coast and depend on the PLME for feeding. Approximately, 75% of the global population of black-browed albatross live and breed in these waters. More than a million breeding pairs of Magellanic penguins, 72,000 southern sea lions and 60,000 southern elephant seals are home to the PLME. In addition, several seabird and marine mammal species migrate yearly to this area coming from sub-Antarctic and Antarctic waters. All these species together, constitute one of the greatest marine wildlife spectacles on the globe.

The PLME sustains one of the largest fisheries on the planet. The most important threats to the conservation of the area are overfishing of target species, bycatch, incidental mortality of seabirds and mammals, and the destruction of benthic habitats (with the associated loss in biodiversity) as a result of bottom trawling. Illegal, unregulated, and unreported fishing (IUU) is also threatening important fish and squid species found on the continental shelf and slope off Argentina. In addition, increasing fishing operations in international waters pose serious threats to local fish and squid populations.

Other threats are related to pollution, especially by run-offs and garbage from coastal cities, and also from fishing operations. Also, oil pollution represents a potential threat to the conservation of the area, as important oil transport takes place along the Patagonian coast from oil platforms and extracting sites on land to the refineries located North on the Buenos Aires coast.

Introduced marine species, resulting from tank cleaning and ship transport, also represents a threat to local populations especially along the Patagonian coast.

Page 2 | Patagonian Sea: Conservation in Action