To release or not to release? A call for caution when considering wildlife reintroductions

Abstract

In a global scenario of biodiversity loss, apex predators and large obligate scavengers are common targets of conservation efforts. Management agencies typically focus on individual species and on immediate actions, seemingly neglecting the holistic and long-term scope that lies at the very core of conservation biology. Conservation actions such as captive breeding and the eventual release of individuals can help species at the brink of extinction to recover. However, they sometimes seem to be the ultimate goal, regardless of the conservation status of the species and bypassing the need to pursue long-term ecosystem recovery. Minimizing the factors that drove species to a threatened status and assessing the ecological and societal impacts of reintroductions should be crucial steps before assuming that reintroductions are a priority. We discuss these issues based on ongoing management programs of several species in the Iberian Peninsula. We propose complementary actions that would promote the recovery of species and, ultimately, ecosystem resilience in the long term. Our concerns may prove useful for many other species and ecosystems on a global scale.