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The kea (Nestor notabilis) and other New Zealand forest birds are threatened by predation by introduced mammals. Mammal control for biodiversity conservation in New Zealand commonly involves the aerial application of cereal-pellet baits containing sodium fluoroacetate ('Compound 1080'), but its effectiveness for kea conservation has not previously been assessed. This study examined the effects of aerial 1080 on the reproductive success of kea in a lowland rimu forest on the West Coast of New Zealand's South Island. We measured three parameters which collectively describe annual reproductive success (nesting frequency, nest survival and final chick count), within a Before-After-Control-Impact experiment. The Impact site was a 30 000 ha area over which 1080 baits were aerially applied in the spring of a rimu (Dacrydium cupressinum) mast year (i.e. with heavy seedfall), with the After phase of the experiment lasting for two kea nesting seasons. The invasive mammals ship rat (Rattus rattus), brushtail possum (Trichosurus vulpecula) and stoat (Mustela erminea), which are potential predators of kea nests, were much less abundant in the Impact site after 1080 application, on the basis of standard indexing techniques. There was strong statistical support for an effect of aerial 1080 on kea nest survival. Aerial 1080 improved the odds of daily nest survival by a factor of 9.1 at the treatment site. Nest survival rates in the Control and Impact sites, before the application of 1080, were 21% and 46.4%, respectively. After the application of 1080 to the Impact site, nest survival increased to 84.8% in this site, whereas it declined to 12.2% in the untreated Control site. This substantial positive effect of aerial 1080 on kea nest survival is attributed to the effective control of mammalian nest predators, particularly the secondary poisoning of stoats.

Parrots are one of the most complex avian lineages worldwide, yet little is known about their patterns of movement and space use. Such information is vital for understanding the social development and structure of members of this long-lived order, as well as for the establishment of effective conservation and management actions for the many threatened or endangered species. While global positioning system (GPS) telemetry has been employed successfully on a broad range of birds, to date no studies have been published in which this technology has been used on any psittaciform species, most probably due to concerns held by researchers regarding the high cost of GPS units or the perceived ability of members of this order to remove or damage tracking gear. Here, we evaluate the feasibility and performance of animal-borne GPS telemetry as a means of tracking parrots. First, we encased inexpensive (,US$70) archival GPS dataloggers (~19 g) in bite-proof housing, and then we evaluated the effects of the devices on the study animals and their operational performance during field trials (n ¼ 14) on wild-caught Kea (Nestor notabilis), a large (~1 kg) parrot endemic to the Southern Alps of New Zealand. We observed no apparent adverse effects of the loggers on the behavior and condition of the Kea and no damage to the devices that impaired their function, and found that the operational performance of the loggers was similar to that reported for devices deployed on other birds and animals. Our study demonstrates that GPS telemetry can be a highly effective method for characterizing the movement patterns of free-ranging parrots.Estudio de factibilidad del uso de telemetría GPS para loros: Un caso de estudio con Nestor notabilis RESUMEN Los loros son uno de los linajes de aves sociales más complejos del mundo, y sin embargo poco se sabe sobre sus patrones de movimiento y uso del espacio. Esta información es vital para entender el desarrollo social y la estructura de los miembros de este orden de larga vida, así como para el desarrollo de acciones efectivas de conservación y manejo para muchas de las especies amenazadas o en peligro. Mientras que la telemetría con sistemas de posicionamiento global (GPS por sus siglas en inglés) ha sido usada conéxito en una amplia gama de aves, no hay estudios publicados donde se haya usado esta tecnología con ninguna especie de Psitaciforme, probablemente debido al alto costo de las unidades GPS o a la habilidad potencial de los miembros de este orden para sacarse o dañar los equipos de rastreo. Aquí evaluamos la factibilidad de uso y el rendimiento de la telemetría GPS desde el nacimiento de los animales, como un medio para seguir a los loros. Primero, revestimos un registrador de datos de GPS (~19 g) barato (,$70 USD) en un envase a prueba de mordidas y luego evaluamos los efectos de estos equipos en los animales de estudio y su rendimiento operativo en las pruebas de campo (n ¼ 14) en individuos cautivos de Nestor notabilis -un loro grande (~1kg) endémico de los Alpes del Sur de Nueva Zelandi...

The kea (Nestor notabilis) is a highly intelligent and adaptable omnivorous New Zealand parrot. These traits potentially put kea at risk of poisoning during vertebrate pest poisoning operations. However, as kea fall prey to introduced pests, they also gain from pest control, creating a cost-benefit situation. Pest control in kea habitat is mainly by aerial 1080, the distribution of sodium fluoroacetate poison pellets by helicopter. Understanding the net outcome for kea of this pest control method is extremely important because kea are endangered and aerial 1080 use is controversial. We use 222 monitoring cases of individually marked kea at 19 aerial 1080 operations to model kea survival of aerial 1080 operations with respect to five variables. Proximity to human-occupied sites where kea scrounge human food was inversely related to survival; the odds of survival increased by a factor of 6.9 for remote kea compared to those that lived near scrounging sites. High survival in remote areas is explained by innate neophobia and a short field-life of prefeed baits, which together preclude acceptance of poison baits as familiar food. Elevated risk to kea living near scrounging sites is explained by learned neophilia, possibly exacerbated by lead poisoning. Survival was also related to the history of aerial 1080 treatment at a site; the odds of survival increased by a factor of 21.3 at sites with repeated operations compared with first time treatments. This effect is possibly due to selection for neophobic phenotypes. We suggest that 1080 poisoning risk management for kea should focus on reducing human food availability through an advocacy campaign. If most kea have not been fed by humans, then the long term outcome of the South Island aerial 1080 programme should be positive for the kea.

ContextFeral cats have benefitted from effective control of foxes in south-western Australia and, consequently, their impact on some threatened mammal species has increased. Control of feral cats in the region can be enhanced by use of the Eradicat® cat bait, but its impact on non-target animal populations requires investigation before widespread use. AimsThe aim of the present study was to determine through field trials whether consumption of Eradicat® baits by resident red-tailed phascogales, following a broadscale baiting operation to control feral cats, was sufficiently frequent to cause significant rates of mortality in wild populations of phascogales. MethodsNine radio-tagged red-tailed phascogales were monitored through an Eradicat® baiting event to determine their survival. Removal and consumption of toxic and non-toxic rhodamine B-labelled baits by a range of species were monitored with camera traps and by subsequent trapping of red-tailed phascogales and other mammals to sample whiskers for evidence of rhodamine uptake. Key resultsAlthough some phascogales showed interest in baits and sometimes moved them from the deposition site, all radio-tagged phascogales survived for at least 1 week after baiting, by which time very few or no baits remained. Examination of whiskers sampled from individuals exposed to rhodamine-labelled baits showed that consumption of non-toxic Eradicat® baits by phascogales was negligible; only one phascogale of 62 sampled showed any rhodamine banding. ConclusionsThe present study provided no evidence that red-tailed phascogales in the study region are at risk from an Eradicat® baiting episode in autumn. ImplicationsThe risk to red-tailed phascogale populations through the use of Eradicat® baiting to control cats in their habitat in the Great Southern region of Western Australia is likely to be low. Further research to elucidate any impact of repeated baiting on populations of this species at several locations is recommended.