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Item Breeding ecology of a translocated population of red-crowned kakariki (Cyanoramphus novaezelandiae) on Tiritiri Matangi island, New Zealand : a thesis submitted in partial fulfillment of the requirements for the degree of Master of Sciences in Ecology at Massey University, Albany, New Zealand(Massey University, 2006) Ortiz-Catedral, LuisThe reproductive ecology of a translocated population of red-crowned kakariki (Cyanoramphus novaezelandiae) was monitored during 2004-2006, covering two breeding seasons on Tiritiri Matangi Island. Red-crowned kakariki nested in tree cavities, ground burrows and in vegetation clusters located in forest remnants, grasslands and replanted vegetation as well as in nestboxes. There was a marked difference in reproductive success between the two breeding seasons. In 2004-2005 1.4 fledglings per breeding pair were produced. In contrast. 3.4 fledglings per breeding pair were produced in 2005-2006. This increase was the result of changes in loss rate during the nesting cycle. Nest failure occurred in 57% of nests in 2004-2005 whereas only 8% of nests were affected in 2005-2006. In both breeding seasons, incubation was the main stage of losses. Clutches hatched with various degrees of asynchrony. Brood sizes ranged from one to nine nestlings. Within broods, nestlings of different hatching ranks reached similar mass at fledgling. Likewise, nestlings of different hatching ranks gained similar weight over the linear portion of the growth curve and grew wings at a similar rate. However, last hatched nestlings fledged with shorter wings. Furthermore, mortality was higher for last hatched nestlings. Sex ratios at the clutch level and at fledgling did not deviate from parity. However, at the clutch level there was a higher proportion of males in clutches laid early and middle in the breeding season. Various lines of evidence suggest that food availability has a direct effect on reproductive success of red-crowned kakariki and can exacerbate the costs of asynchronous hatching. Therefore it is a priority to investigate natural changes in food resources of the red-crowned kakariki and to assess the potential of direct management to improve the conservation of the species.Item Aspects of the biology of managed populations of two Cyanoramphus parakeet species in New Zealand : breeding biology, pathogen screening and translocation : a thesis submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Conservation Biology at Massey University, Auckland, New Zealand(Massey University, 2011) Ortiz-Catedral, Luis; Ortiz-Catedral, LuisIn this study, a visit to the remote Kermadec archipelago and the translocation of two parakeet species to novel sites opened up opportunities to document aspects of the biology of free-living and captive-bred parakeets. Four years after the eradication of cats and rats on Raoul Island by the Department of Conservation, the Kermadec redfronted parakeet has naturally recolonised this site, potentially from the adjacent Herald Islets. Over a period of three weeks in March-April 2008, 100 parakeets were captured on Raoul Island and the first evidence of nesting of the species at this site since 1836 was recorded. These observations reinforce the view that eradication of introduced predators such as cats and rats is a requisite for the recovery and establishment of populations of New Zealand parakeets. These observations also suggest that strategic eradication of cats and rats can facilitate the natural dispersal of parakeets. Taking into account the remarkable recolonisation of parakeets on Raoul Island and the existence of islands free of introduced mammalian predators and red-fronted parakeets in the Hauraki Gulf, a translocation of parakeets was envisaged. Between April and May 2008, 32 red-fronted parakeets were translocated from Little Barrier Island to Motuihe Island, in the first translocation of the species within the Hauraki Gulf in 32 years. Alongside such transfer, a total of 62 captive-bred Malherbe’s parakeets were monitored on Maud Island, in the Marlborough Sounds. Because the translocations of red-fronted and Malherbe’s parakeets were temporally close, a unique opportunity to study translocated free-living and captive-bred parakeets was identified. The focus of monitoring on both sites was the detection of successful nesting attempts, a short-term measure of translocation success. On both sites (Motuihe and Maud Islands) evidence of successful nesting was found within a year of the release of the first flocks. As part of the planning steps for the translocation of red-fronted parakeets, a survey was designed for four selected microorganisms of conservation concern for New Zealand parrots: Campylobacter, Salmonella, Yersinia and the beak and feather disease virus (BFDV). Only the latest was detected at a prevalence of 28% on Little Barrier Island. Subsequent isolation and sequencing of BFDV genomes revealed a previously undescribed genotype of this virus in New Zealand. The discovery of a new BFDV genome in a wild population of endemic New Zealand parakeets highlights need of future research. BFDV is known to affect the immune system and survival of infected individuals in other species and is likely to hamper conservation efforts for threatened parrot species. The challenges to study BFDV in New Zealand, a global hotspot of parrot diversity, are outlined and high priority lines of research are identified and discussed.