Abstract: Hutton’s shearwater (Puffinus huttoni) is a burrowing petrel endemic to the alpine zone of the Seaward Kaikōura Ranges, New Zealand. In November 2019, we accessed an understudied breeding colony at Shearwater Stream in the Puhi Peaks Nature Reserve for the first time since a Mw 7.8 earthquake struck the region in 2016. We measured population parameters and carried out a geomorphological assessment. We estimate that the Shearwater Stream colony supports approximately 3,000 breeding pairs. Ground deformation attributed to the 2016 earthquake did not explain the discrepancy between this estimate and the commonly cited (pre-quake) population estimate of ~8,000 pairs. We highlight the limitations of extrapolated population parameters and of using vegetation cover as a coarse proxy for colony area. We discuss how low burrow occupancy and long-term reductions in the availability of suitable habitat indicate a population at risk of decline. We highlight how stable long-term data for burrow density and breeding success may not be reliable indicators of population health at Shearwater Stream.
Abstract: A new colony of the endangered Hutton’s shearwaters (Puffinus huttoni) has been established at Te Rae o Atiu on the Kaikōura Peninsula, South Island east coast, New Zealand to provide insurance against catastrophic events at the high-altitude natural colonies in the Kōwhai River and Shearwater Stream, Seaward Kaikōura Range. The translocation of 495 chicks from the Kōwhai River colony was carried out in six operations from 2005 to 2013. Of the 473 fledglings, 97 have been recorded back at Te Rae o Atiu. Chick selection criteria, fledgling mass, fledgling wing length, days present before fledging, and days of emergence before fledging had no bearing on whether chicks returned from their post-fledging migration to Australian waters or not. One hundred and twelve Te Rae o Atiu bred chicks have fledged up until 2020–21. The Te Rae o Atiu fledglings had similar mass and wing lengths, and days emerged prior to fledging, to the translocated fledglings. There were no differences between the groups of Te Rae o Atiu bred birds that returned or did not. At 2020–21, 21 of the 112 second-generation chicks have returned from their initial migration, and the earliest have bred successfully. The colony has grown to about 75 birds producing about 30 eggs, 24 chicks, and 22 fledglings annually. Future growth of Te Rae o Atiu will be reliant on these home-bred chicks as the oldest translocation birds will soon be approaching the end of their breeding lives. Acoustic attraction of birds flying over Te Rae o Atiu from the sea towards the Kōwhai River natal colony has been mostly unsuccessful with only two birds attracted.
Abstract: The critically endangered kuaka Whenua Hou (Whenua Hou diving petrel, Pelecanoides georgicus whenuahouensis) is a burrow-nesting petrel, restricted to breeding in the foredunes of Whenua Hou. The species’ recovery is inhibited by ongoing threats such as vessel-based light pollution, interspecific competition, and climate change including storm-induced erosion of fragile breeding habitat and thus, kuaka Whenua Hou would benefit from the establishment of a new colony through translocation. However, translocations of petrels require hand-rearing of pre-fledging chicks on the destination site to reset their philopatric behaviour. We documented a hand-rearing and translocation trial of kuaka Whenua Hou in preparation for future translocations. Ten kuaka Whenua Hou chicks were translocated from natal burrows to nest boxes installed behind the colony, and hand-reared on a bespoke diet of pureed sardines. All hand-reared chicks fledged successfully, with fledging mass similar to naturally-reared chicks and with slightly longer wing lengths. The techniques used highlighted the importance of selection criteria, access to natural growth curves to infer feeding regimes, nutritionally rich diets, and strict hygiene protocols. Our trial provides a knowledge base for future translocations and the establishment of new kuaka Whenua Hou colonies.
Tuhinga whakarāpopoto: He momo tata korehāhā te kuaka o Whenua Hou (Pelecanoides georgicus whenuahouensis), he momo ōi e whai rua hei kōhanga, kua mau ki te whakatipu ki ngā tāhuahua kopī o mua o Whenua Hou. Ko te whakarauora o tēnei momo kua whakanguengue i ngā āhuatanga whakaraerae e mau tonu pērā i te pokanga rama, ā rātou ake pakanga ki a rātou me te hurihuri o te āhuarangi, tae noa atu ki te horonga whenua o te pūrei kōhanga marore nō te marangai, ā nō reira, ka whai hua te kuaka Whenua Hou i te whakatūtanga atu o tētahi taiwhenua hou mā te nukunuku kōhanga. Engari, me whakatipu ngā pīrere ki te ringa ki te wāhi e tū ai te kōhanga hou kia ea ai te nuku kōhanga, ā, kia tautuhi anō tā rātou hiahia ki te hoki atu ki te kāinga i whakatipuria kētia rātou. I āta mārama mātou ki te whakamātautau o te whakatipu ā-ringa me te nukunuku kōhanga o te kuaka Whenua Hou kia whakarite ai ki te nukunukunga tūturu e haere ake nei. I nuku kia ngahuru ngā pīpī kuaka Whenua Hou mai i ngā rua i whānau mai ai rātou ki ētahi kōhanga hanga i whakatūria ki muri i te taiwhenua matua, ā, i whakatipuria rātou ki te ringa ki ētahi kai ake o te hārini penupenu. I whai huruhuru pai ngā pīpī katoa, ā, ehara i te rerekē te taumaha o ēnei pīpī i ērā i whakatipuria ki ō rātou ake kōhanga, engari he paku roa ake ngā parirau. I whakamiramira atu ngā tū-āhua i whakamahia i te hiranga o ngā paearu whiri, te whai wāhitanga ki ngā pikinga whakatipu māori kia whakapae tika ai te tikanga whāngai, te whiringa o te kai taioranga me ngā tikanga akuaku mārō. Ka noho tā mātou whakamātautau hei tūāpapa mātauranga ki ngā nukunukunga kōhanga e haere ake nei, me te whakatūtanga o ētahi taiwhenua hou mō ngā kuaka Whenua Hou.
Abstract: Captive facilities across New Zealand strive to mimic natural conditions for captive animals as closely as possible. In the case of the kiwi (Apteryx spp.), captive habitats are augmented with natural stimuli such as soils, leaf litter, bark, plants, logs, and mosses. Interaction with these introduced stimuli has been shown to encourage normal foraging behaviour and is speculated to aid in inoculating young animals with healthy microbial communities. However, introducing non-sterile natural stimuli into the captive environment also carries the risk of exposing kiwi to diseases such as aspergillosis, coccidiosis, and candidiasis. Aspergillosis is of particular concern to rearing facilities – the disease is most commonly attributed to exposure to Aspergillus fumigatus, an opportunistic fungal pathogen. Here we present a PCR-based screen to qualitatively detect the presence and/or absence of A. fumigatus in soils. Soil samples collected from nesting sites of rowi (Ōkārito brown kiwi, Apteryx rowi) in the Ōkārito region of the West Coast were screened for A. fumigatus using a species-specific primer set coupled with a basic DNA extraction. Willowbank Wildlife Reserve soil and substrate samples were also screened as a baseline comparison representing captive rearing facilities. Results from the assays showed that the extraction technique was effective at isolating A. fumigatus DNA at detectable levels from a variety of soils, and that Ōkārito soils did not harbour a higher abundance of A. fumigatus than those found at Willowbank. This preliminary screening method could be used by facilities in New Zealand to quickly and cheaply screen soils and substrates for A. fumigatus before introducing them to captive enclosures.
Abstract: The species composition of moa assemblages reflected the local vegetation. These assemblages have been used as indicators of the geological age – glacial or Holocene – of the fauna. Within the assemblages, some species of moa have been associated with specific vegetation types, including Anomalopteryx didiformis with lowland rain forest, and Euryapteryx curtus, with dry shrubland. The sequence of radiocarbon ages for A. didiformis and E. curtus in the Waitomo karst, in the west central North Island, New Zealand, records changes in the distributions of their habitats over the past 28,000 years. The presence of A. didiformis shows that, contrary to current reconstructions, there was lowland rain forest in the karst during the Last Glacial Maximum. An abrupt change to E. curtus and hence of its shrubland habitat coincided with the Oruanui super eruption of Taupo volcano 25,400 years ago. Anomalopteryx didiformis and its rain forest habitat did not return to the karst until c. 13,000 years ago. E. curtus disappeared from the karst some time before that, during the gradual post-glacial warming, but remained elsewhere on the Volcanic Plateau, probably in the seral vegetation that followed the continual eruptions. Moa distributions were not always altered just by climate change. Major eruptions such as the Oruanui could change their habitat and hence their distribution over much of both main islands.
Abstract: House mice (Mus musculus) have proven to be the most difficult introduced mammal to eradicate from (and keep out of) New Zealand reserves and sanctuaries. Partly as a consequence of this, little is known about how bird communities respond to mouse eradication. Mice were successfully eradicated from 217 ha Mana Island Scientific Reserve, near Wellington, in 1989–90. Five-minute bird count surveys undertaken in spring and autumn before and after mouse eradication revealed that 13 of 22 species were recorded significantly more often after mouse eradication, and just two species were recorded significantly less often following the eradication (and each of these in one only of the two seasons that were compared). Four species had no significant change, and three species showed mixed responses between the two seasons. While the overall pattern was of increased relative bird abundance after mouse eradication, there is limited information on why individual bird species increased during the study period, and whether this was a consequence of mouse eradication. Bird count data revealed that insectivorous passerines may have benefited the most from mouse eradication on Mana Island, suggesting that competition for invertebrate prey was the main impact that mice had on the birds of the island. The use of anticoagulant rodenticides to eradicate mice from Mana Island had little detectable impact on populations of the island’s birds.