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New Zealand conservation managers have a distinguished history in translocating forest birds, shorebirds and waterfowl to achieve conservation gains. Although New Zealand is a centre of seabird diversity, and many species are threatened and/or have suffered human-induced range reductions, until recently there had been few attempts to translocate seabirds. Reluctance to attempt translocations was due largely to the perceived risk of dispersal, and the expectation that birds would return to their source colony. Translocations have now been attempted with 10 species of burrow-nesting petrels in New Zealand, with chicks moved before they were likely to have developed awareness of their natal colony location, and hand-fed until they fledged. The translocation of 240 fairy prion chicks from Takapourewa (Stephens I) to Mana I in 2002-04 was one of few petrel translocation studies where systematic searches for returning translocated chicks at both the release site and the source colony were undertaken, and where a sample of marked control chicks allowed comparison of natural return rates with those of translocated chicks. Twenty translocated chicks returned to Mana I during 2004-12, and 25 were recovered at the source colony during 2005-08. Nearly identical proportions (c.20%) of translocated and control chicks were recovered, with higher recovery rates at the release site for each successive cohort. Birds appeared to develop their homing ability at different ages, and there was no apparent maximum age after which chicks should not be translocated. Exposing chicks to the source colony surface in daylight did not increase the risk of them returning to the source colony.

Translocations (deliberate movement and release of wildlife) have been of crucial importance in the management of New Zealand threatened birds, and as part of site restoration projects. We review attempts to translocate New Zealand birds for conservation reasons since 1863. Following an early pulse from 1895-1908, there was concerted and increasing effort (both in the number of translocations and the number of taxa translocated) and success since the early 1960s. Sixty- eight taxa (55 species) of New Zealand birds have been translocated in over 1100 separate releases, with new populations of 50 taxa (41 species) successfully established. Translocations of 9 further taxa (7 further species) are in progress. Overall, 61% of New Zealand’s extant endemic waterfowl, shorebird and landbird taxa have been translocated (51% of the total successfully, with an additional 4% in progress). Five taxa exist solely as translocated populations (little spotted kiwi Apteryx owenii, buff weka Gallirallus australis hectori, kakapo Strigops habroptilus, South Island saddleback Philesturnus carunculatus and black robin Petroica traversi), and 10 further taxa would be confined to single wild populations but for successful translocations. Most translocations were undertaken within historical ranges, however, 6 taxa have been established beyond their historical ranges, with attempts for 2 further taxa in progress.

The North Island kokako (Callaeas wilsoni) is a threatened endemic passerine whose distribution has declined greatly on the New Zealand mainland due primarily to predation by ship rats (Rattus rattus) and brushtail possums (Trichosurus vulpecula). It persists in 21 populations, of which 10 (48%) have been established by translocation, and 1 has been supplemented by translocation. Of the 11 populations subject to translocation, 4 are on islands and the remainder are on the mainland; 7 translocations have resulted in successful new or supplemented populations and another 4 translocations are in progress. Translocations to another 5 sites did not establish breeding populations for various reasons. In total, there were 94 translocations of 286 kokako to the 16 sites, and the number released at a site averaged 18 (range 3-33) birds. Kokako were released at a site over an average period of 49 months (range 1-159 months) with a mean of 3 birds (maximum 10) released per day. The small numbers of kokako released and the long time required to complete a translocation were due to the difficulty and high expense of catching kokako. Translocations will continue to be important for the conservation of this species, to establish further new populations and to limit inbreeding depression and allele loss in existing populations.