Facing the 2013 Gold Rush: A Population Viability Analysis For the Endangered White-lipped Peccary (Tayassu pecari) in Corcovado National Park, Costa Rica

Rivera, Christian J. [Browse]
Senior thesis
50 pages


Wilcove, David S. [Browse]
Princeton University. Department of Ecology and Evolutionary Biology [Browse]
Class year
Summary note
The white-lipped peccary (Tayassu pecari) is facing range-wide declines throughout the Neotropics. It has been eliminated from about 89% of its historical range in Costa Rica. Corcovado National Park, in the Osa Peninsula of Costa Rica, is the last remaining stronghold for the white-lipped peccary in the country. In 2006, 30 people were reported mining in the Park. In 2013, Corcovado National Park experienced a sudden gold rush that is attributed to the poor socioeconomic conditions of the Peninsula. The gold mining operations brought with them a wave of 250 miners and vigorous hunting pressures on the white-lipped peccary population and the rest of the fauna in the Park. Given that the species is endangered and is susceptible to hunting due to its herding behavior and tendency to cohere and attack when threatened rather than flee, it is important to assess its probability of extinction under various hunting scenarios. Incorporating data from studies on the life history of the species throughout its range in the Neotropics and in Corcovado, I used the population viability analysis software VORTEX to simulate the population trajectories and probabilities of extinction of the species under current hunting pressures. Furthermore, I extended the model to simulate probabilities of extinction under various management scenarios where the numbers of miners hunting is reduced. The results of this study revealed that under the status quo where 250 miners are present in the Park, the population of white-lipped peccaries has a about a 40% chance of extinction within five years and about a 99% chance of extinction within 10 years. Moreover, there is an “extinction threshold” for the population between the presence of 100 and 150 miners hunting in the Park. At this threshold, the population growth rate, r, drops from a positive growth rate (r = 0.09, SD = 0.08) to a negative one (r = -0.07, SD = 0.29). I suggest that anti-mining and anti-poaching laws be enforced immediately, and that the number of miners be reduced to 100 at a minimum, if not completely, in order to ensure that the population of white-lipped peccaries becomes viable and evades a local extinction.

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