Introduction

The intentional movement by humans of an animal or a population of animals from one location with free release at another to re-establish a species which has been lost, or supplement existing populations, has become an important tool in conservation biology (Fischer & Lindenmayer, 2000; Seddon et al., 2007). A common goal of many animal translocations is the establishment of self-sustaining populations. Animals may be sourced from other wild populations or from captive-stock. From an ecological perspective, the implications of where the animals originate, and therefore how prepared they may be for independent life post-release, and whether release site habitats are able to support viable populations, needs assessment. Re-establishment of species in areas from which they have been extirpated has never been intended to be the only means to conserve biodiversity. But, this is a particularly useful approach that is likely to be used increasingly in the coming decades, as numbers of critically endangered species rise (Chapter 3), or as some advocate if assisted colonisation of species (also referred to as managed relocation, assisted migration, or assisted translocation) becomes a realistic intervention strategy in biodiversity management under climate change (Hoegh-Guldberg et al., 2008).