Translocation of individuals to offshore managed islands or "sanctuaries" is at the core of conservation in New Zealand. For the critically endangered Malherbe's parakeet, translocation to Maud, Chalky and Tuhua (Major) Islands represents the difference between survival and extinction. Historically found only on mainland New Zealand, Malherbe's parakeets are bred in captivity, carefully reared and subsequently released onto islands free of mammalian predators and competitors, two threats faced by the few remaining mainland parakeets. Since 2005, numerous individuals have been released onto these islands. However, monitoring Malherbe's parakeets and determining how successful a translocation has been are difficult tasks. In 2007, we started the first project aimed at documenting the breeding biology of the species on an island site: Maud Island. Using the Maud Island population of this species, we have developed a survey methodology to estimate population growth. Along the way we have collected information about the biology of the species in the wild, crucial to maximise the effectiveness of captive-breeding and translocation. Ourproject has generated the first population estimate for this critically endangered specieson an island: 97 individuals from an initial founder flock of 11 captive-bred parakeets. This finding indicates that Maud Island is an important stronghold for the species and currently has nearly 40% of the global population estimate. This methodology is now being used on other populations of parakeets. In coming months, other islands such as Tuhua(Major) and Chalky Island will also count with an updated population estimate. This information is critical to re-assess the conservation status of one of New Zealand's rarest bird species. Besides developing a methodology to monitor parakeets and estimate population size based on sightings of banded individuals, we have also obtained information about the health of parakeets. In November 2009, some individuals with signs of abnormal feather loss were photographed and since then we have conducted tests to detect potential causative agents. Overall, this project has significance at a regional and international scale as lessons learnt with Malherbe's parakeets can be applied to other closely related species in Australia and other islands of the South Pacific.