The Pampas ecoregion
The approximate extent of this extensive ecoregion is 500,000 km2, including the provinces of Buenos Aires (except its southern extremity), northeastern La Pampa, southeastern Córdoba, southern Santa Fe, and Entre Ríos. Some studies also consider the grasslands in the provinces of San Luis and La Pampa to be part of this ecoregion. The climate in this area ranges from temperate-humid to subhumid, with precipitation varying from 600 to 1,000 mm and average annual temperatures between 15 and 18 °C.
The plain is characterized by a gentle relief only interrupted in the south by the mountain ranges of the Tandil and Ventania Systems, with heights of 500 and 1,000 meters above sea level, respectively. This region, classified as one of the most fertile in the world, is and has been since the late 19th century, the center of significant economic investments in the country, leading to significant transformations of its original landscape. Initially covered by a temperate grassland dominated by the flechillar community (grasslands with species of Stipa and Piptochaetium), today the predominant plant species in natural grasslands include Festuca ventanicola, Senecio leucopeplus, Sorghastrum pellitum, Paspalum quadrifarium and Cortaderia selloana . The region is primarily dedicated to the cultivation of cereals and oilseeds, as well as cattle farming. In recent decades, as a result of the modernization of agricultural technologies, the cultivated area has increased significantly (only corn, soybeans, and sunflower cover 30% of the region), and fields remain under crops for much of the year (second crops). Although sheep farming experienced a boom from the late 19th century until 1940, its significant decline began in the 1970s, and currently, most fields only maintain sheep for consumption purposes.
This ecoregion due to soil characteristics, climate (precipitation), etc., is subdivided into different subregions (see map). Subregion A corresponds to the Ondulated Pampa. B to the Interior, C to the Austral, and D to the Flooded. It is important to note that agricultural and livestock activities vary according to these subregions.
In this ecoregion, the puma has a greater presence and conflict with ranchers in the Austral Pampa and the Interior Pampa. The puma's natural prey in the Pampas include, in terms of native species, the rhea (American Rhea), the capybara (Hydrochoerus hydrochoeris), the viscacha (Lagostomus maximus), the coypu (Myocastor coypus) y a tres especies de Dasipódidos y, dentro de las exóticas, al ciervo colorado (Cervus elaphus), fallow deer (Dama dama), axis (Axis axis), jabalí (Sus scrofa), antílope negro (Antilope cervicapra), the European hare (Lepus europaeus). The puma has already begun to recolonize the Bahía de Samborombón area, so current or future predation on the Pampas deer (Ozotoceros bezoarticus) (which once, along with the rhea, was its main prey) is not ruled out.