The reintroduction of a species in a natural environment is defined as the introduction of individual(s) in a territory where the species is no longer present. This operation is rare because it is difficult to undertake, expensive and highly regulated.
Its main objectives are to improve species’ long-term chances of survival and to restore biodiversity. Reintroduction also contributes to raising awareness about nature conservation and plays a role in improving local and national economic development. Nevertheless, the process needs lengthy preparation in order to avoid potential negative effects on the ecosystem where the individuals are introduced. In this context, it is essential to undertake a feasibility study in order to understand the causes of the species’ disappearance, to evaluate the effects of this operation on the environment, and to establish its chances of success.
The individual animals used for reintroduction are preferably wild, but they can come from captivity and in this case they will have been reared with this purpose in mind. Stringent international regulations, notably from the CITES (the Convention on International Trade in Endangered Species of Wild Fauna and Flora) and national laws, govern this kind of transfer. For example, tigers can only be reintroduced to a certain environment if the original causes of the wild animals’ disappearance from that environment are no longer present or are strongly reduced. Moreover, the animals have to be numerous enough to be able to meet, to reproduce, and to renew the population.
The reintroduction of tigers requires a high level of expertise and a multi-disciplinary approach. Young felines spend a long period of time alongside their mother learning the skills necessary for survival in the wild (recognising dangers to avoid, prey, hunting techniques, and the behaviours to adopt in the presence of other tigers). In captivity, humans have to enable this learning to take place whilst also minimizing the extent to which the tigers become accustomed to human contact. This is particularly important for avoiding conflicts with local population (attacks on children or livestock…).
Indeed, the tiger has to be subject to careful monitoring as it can cover long distances, going close to villages. Its new habitat must be big enough and rich in biodiversity, particularly in prey, to reduce the risk of conflict. Although many tiger reintroduction projects are in the preparation phase (feasibility study in China, in Kazakhstan…), they have not yet reached the animal introduction phase. Until now, tigers have only been moved into environments from which the species has not completely disappeared. They have been transferred – not reintroduced.