Conservacion Patagonica IDIOMA: ESPAÑOL

Overgrazing and Desertification

Desertification in the Southern Cone

For centuries, Patagonia's vast expanses of arid grasslands supported large herds of wild herbivores grazing on native grasses and scrubs. However, the introduction of sheep (and occasionally cattle) ranching in the early 20th century quickly destroyed this ecological balance. Although these hardy pioneers in Patagonia displayed admirable fortitude in braving the harsh climate, they established a system of land use that could not thrive given the region's geography and ecology. Stocking rates were consistently over 60% above the estimated carrying capacity of the land. Domestic animals, particularly sheep, inflict far more damage on grasses as they graze than do native herbivores.

The result: vast areas of remote and undeveloped Patagonia approach irreversible ecological collapse. As livestock strips an area down to minimal vegetation, a downward spiral begins. Sheep are selective grazers and long-standing irresponsibility in management has intensified grazing patterns of uneven utilization. This inequity in grazing can lead to animal distribution levels that vary from 8 to 20 times the total stocking rate of a given pasture. This grazing pattern makes it virtually impossible for certain plants to recover. More and more woody, unpalatable plants dominate the landscape as livestock selectively eat grasses and not these scrubs, rendering the land less productive for both livestock and wildlife.

Damaged grasslands retain less moisture, continuing to break up ground cover and further inhibiting the re-growth of native, perennial plants that are more capable of sabsorbing carbon dioxide and enriching soil. Meanwhile, diminishing vegetation cover leaves sandy soils vulnerable to wind erosion from Patagonia's notoriously fierce winds. Like in regions of Africa bordering the Sahara, vast areas of Patagonia have already turned to desert, virtual dead zones for flora and fauna.

Damaged grasslands are vulnerable to wind erosion

Cattle ranching in Patagonia

These ecologically damaging practices have proven economically unsustainable as well. Although drastically lower stocking rates might make sheep ranching ecologically responsible, such a system would not be economically viable in much of the region given its remoteness, severe climate and the relatively low global price of meat and wool. The Patagonian sheep industry, which began less than a century ago, peaked in 1952, with over 21 million sheep in the region. Since then, the livestock industry has contracted; by 1999, only 8.5 million sheep remained in the region. Competition on the world wool market from Australia combined with ecological decline from overshooting the carrying capacity of the land to make raising livestock a poor economic base for the region. Many historic estancias have been abandoned as desertification has rendered them economically unviable.

Severe desertification affects ~30 % of the region. Even worse, over 90 % of Patagonia suffers from some degree of degraded soils, mostly because of unsustainable land use exacerbated by natural forces of erosion. Studies have found that in no area of Patagonia have the impacts from grazing been negligible. Throughout Chile and Argentina, the desertification of Patagonia is widely recognized as one of the most urgent ecological problems. Government ministries in Chile and Argentina confirm that overgrazing must end to avoid further—often irreversible—damages.

Erosion due to overgrazing

Grasslands recover and wildlife returns

Luckily, there is hope for reversing this plight. After just five years free of livestock, the grasslands of the Chacabuco Valley, the heart of the future Patagonia National Park, have made impressive and visible strides towards recovery. Through pioneering ecosystem restoration practices, we aim to establish this project as a model initiative for restoring health to Patagonia.