Promoting sustainable use of wild animals and plants is a global target in biodiversity conservation. However, the role of wild species harvest as a conservation tool remains controversial. When unsustainable, wild harvesting leads to population decline or even extirpation of species. When sustainable, it has the chance to promote win-win solutions for conservation and development. This is particularly important for developing countries where solutions integrating development and conservation are imperative. Here, we reviewed 87 cases of wild harvesting of vertebrates and plants in developing countries to understand the conditions that lead to sustainable versus unsustainable harvest outcomes. We considered characteristics of the species (e.g. resilience and resource type), the type of use (commercial or subsistence) and key socio-economic indicators such as GDP per capita, poverty ratio and human population density as potentially important variables that may affect the likelihood of a wild harvest being sustainable. We used random forest classification and logistic regression to find the most important predictors among those variables, and to detail the predicted effects on sustainability of harvest.
Results/Conclusions
Species resilience, GDP per capita and poverty headcount ratio were the strongest predictors of sustainability. Species resilience was positively related to sustainability of harvest, whereas GDP per capita and poverty ratio were negatively related. Harvesting a low-resilient species in a scenario of middle-income level and high poverty ratio seems a recipe for population decline. On the other extreme, harvesting a high-resilient species under low-income level and low poverty ratio seems much more likely to achieve (but not guarantee) a sustainable harvest. The interactions between species biology, the economic performance and the proportion of people living below the poverty line make predicting the outcome of harvesting something of a moving target. The challenge of harvesting wild populations in a sustainable way seems to be most difficult in growing economies with high poverty rates. Given that size of the economy and poverty ratio are conditions that are unfeasible to manipulate for most managers and decision makers, setting informed harvesting restrictions, investing in law enforcement and enhancing management practices are all key to sustainable harvest. This study highlights the risks of wild population harvest under the challenging socio-economic conditions inherent in developing countries. It also helps to visualize where efforts and resources are most needed to achieve sustainable harvest.