Problems encountered by individuals in animal translocations: Lessons from field studies

The translocation of animal species, that is the transfer of individuals from a source population to a release area to restock, is a widespread practice in conservation biology and wildlife management. However, translocation is likely a severe test for the translocated individuals as they are subjected to stressful and inevitable disturbances: physical handling, transport and release into an unknown environment. Moreover, other disturbances may be induced by translocation, for example in case of social disorganization among translocated individuals or of a large difference in habitat quality between origin and release areas. These disturbances induced by the translocation process may have a negative impact upon the translocated individuals, through reduced survival or breeding success, or abnormal behaviour. Consequently, founding a viable population by the mean of a translocation is not easy. Then, it is necessary to determine which factors are involved in the failure or the success of a translo...