Cabo Dos Bahías y el manejo del guanaco en la Patagonia argentina

Abstract

In 2000, a massive die-off resulted in a drastic reduction of the guanaco (Lama guanicoe) population of Cabo Dos Bahías Reserve, Chubut, Argentina. This event became an emblematic example of guanaco population dynamics in which it is presumed that the lack of regulatory mechanisms induced a population excess that damaged forage resources to an extreme that the population crashed due to starvation. Although this case poorly represents the relevant ecological scenarios, it has a disproportionate influence on current debates regarding the management of guanaco populations. Some authors even claim that, unless guanaco populations are culled, this degradation process will propagate across Patagonian rangelands. In this paper we aimed to synthetize the available evidence and to socialize the results obtained after 15 years following guanaco and vegetation dynamics at Cabo Dos Bahías to contribute to the discussion on the causes and consequences of mentioned guanaco die-off. The available evidence shows that population density is compatible with forage availability and it is coupled with its inter-annual variability. Range condition at the reserve is similar or better, upon the indicator considered, than range condition at neighbouring ranches with traditional livestock management. Our analysis indicates that, although Cabo dos Bahías presented high guanaco densities, which fluctuated more than other populations, there is no evidence to support the lack of regulation, population excess or environmental damage. Finally, we discuss our results in the context of the current debate about guanaco management in Patagonia.