Thursday, October 20, 2011

The Nature of Patagonia

Ecologically diverse, sparsely populated and rich in spectacular landscape, Patagonia covers 800,000 square kilometers across southern South America; this includes all of Argentina south of the Rio Colorado and Chile south of Puerto Montt. A product of Andean volcanism, glacial and stream erosion and cold ocean currents, Patagonia hosts a magnificent diversity of flora and fauna.

As the Atlantic began to open, 160 million years ago, the oceanic Farallon Plate began to subduct beneath the North and South American Plates that were forced toward the west; the Nazca Plate, a remanant of the Farallon, continues to subduct today. Volcanism above this subduction zone has produced the Andes Mountains along the west edge of South America and Patagonia is a composite of volcanic bedrock, lava flows, ash deposits and Tertiary sediments, since molded by glacial and stream erosion. The Chilean segment, which extends to Cape Horn, is a landscape of rugged peaks, ice fields, islands, fjords and sea channels while the Argentine segment includes the eastern flank of the Andean Chain, a vast central plateau of high desert, gravel plains, ephemeral lakes and grassland steppes and the varied coastline of the South Atlantic. The cold Chilean and Malvinas currents, rich in plankton, bathe both coasts of Patagonia, attracting a spectacular diversity of sea birds and marine mammals; the latter include Magellanic, rockhopper and king penguins, albatrosses, southern elephant seals, southern fur seals and southern right whales.

Among the terrestrial wildlife of Patagonia are guanacos, rheas, flamingos, Andean condors, Patagonian fox, pumas, a wide variety of rodents and endemic deer such as huemuls and pudus. Adapting to the harsh environment, these animals inhabit a magnificent yet unsettled landscape; as the Nazca Plate continues to subduct, the Andes rise higher, producing intermittent earthquakes, lava flows and ash plumes. Indeed, the petrified forests of the Patagonian plateau attest to the region's turbulent natural history. To learn more about this spectacular ecosystem and to lend support to its protection, visit The Patagonian Foundation's website, listed in the right column of this blog.