Although animals are best conserved in their natural habitat, the increasing number of threats from human encroachment means that there is often not enough habitat left to support them. Consequently the breeding and care of animals within a zoo or aquarium environment may be one of the only ways these species will be saved by acting as an insurance policy. If a decision to bring an animal under captive management is left until extinction is imminent, it is often too late to save the species.
Reintroduction aims to re-establish a species in an area which was once part of its historical range, but where it has become extinct. Animals for reintroduction can be sourced from captive collections or can be wild animals translocated from other areas.
Reintroduction can be a valuable conservation tool and there are a number of exciting and successful projects in which zoos have played an important role. However, they tend to be very demanding in terms of financial support, resource management and ensuring that the populations being reintroduced are successful. Survival techniques can be lost in captive bred animals so programmes have to be planned carefully, ensuring that the animals have the necessary skills to survive. This may involve pre-release training in antipredator response, and avoiding imprinting by disguising keepers as members of the same species. Long-term post-release monitoring is also essential to evaluate the success of the project.