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The density and distribution of Westland Petrel burrows was assessed over a 12-year period (2007-2019). During that time, burrow density increased while occupancy remained stable, commensurate with an annual population growth rate of 1.022 (95% confidence interval: 0.971-1.076), as estimated using mark recapture data. From our surveys, we estimated a 2019 baseline population of ~6 200 breeding pairs and a world population of 13 800-17 600 individuals, covering around 95% of the population. Transects were conducted to establish the location and density of 17 petrel sub-colonies in rugged, untracked terrain in Paparoa National Park, West Coast, New Zealand. Major storms in 2014-2018 caused widespread treefall and landslides, destroying breeding habitat throughout the species' breeding range. Demographic effects of the major and ongoing habitat loss may continue in the medium to long term, as birds re-establish burrows and partnerships following loss of their habitat. Our study illustrates the complex effects of climate-related disruption on the biology of a long-lived species. With a single nesting area in the West Coast region, climate change will likely have an ongoing influence on the species' global population, since an increase in the frequency of severe weather events, including ex-tropical cyclones, is expected. However, current indications suggest that the species has some flexibility to adapt and to occupy new areas following habitat disturbance. [ABSTRACT FROM AUTHOR]

Threat status assessments provide a benchmark for identifying priorities for conservation and related research for special-status species. We review data about an endemic New Zealand seabird, the Westland Petrel Procellaria westlandica. and provide information to assist future threat assessment reviews. A range of threats have potential or have already contributed to reductions in population growth at a level that may exceed 10% over 10 years (ranked "High" or "High potential" threats). The realised (observed) threats include landslips and extreme climate events that degrade nesting habitat; bycatch mortality in commercial, recreational, and high-seas fisheries; attraction of fledglings to lights; and the potential encroachment of pigs Sits scrofa and dogs Canis familiaris into breeding areas. Low-ranked threats (which may contribute <10% to population reduction over 10 years) include habitat degradation by browsing introduced mammals and land development; death of individuals by striking wires or buildings; disturbance at colonies; the petrels' consumption of fisheries waste and plastics; human harvest; and naturally occurring mortality such as predation by native species or entrapment in tree branches and vines. Population size estimation, demographic modelling, and trend information indicate that the population is small (~2800 breeding pairs), with very low productivity and therefore potential vulnerability to stochastic events. Recent surveys show that the area of breeding habitat occupied by the birds is only about 0.16 km². Storm events in 2014 severely reduced habitat quality, destroyed large parts of some colonies, and increased the likelihood of further erosion and landslip for at least 75% of the global breeding population. Storm impacts at other colonies have not yet been assessed. In light of this information, we recommend immediate review of the threat status of the species and initiation of mitigation to reduce the severity of threats. The information available indicates that a relisting to IUCN Endangered status may be warranted, and that the Agreement on the Conservation of Albatrosses and Petrels threat assessments should be revised to include two high-level potential threats: pig predation and dog predation. [ABSTRACT FROM AUTHOR]

The little penguinEudyptula minoris primarily an inshore forager with its range generally limited to c. 30 km of breeding sites during the nesting period. However, exceptions with greater foraging distances have been recorded in Australia. To investigate the foraging range plasticity in New Zealand we used GPS tracks gathered on 68 individuals in three regions of central New Zealand between 2011 and 2016. Foraging patterns varied between sites and between years. Tracks revealed that penguins can rely on distant foraging areas while incubating, with nesting birds travelling up to 214 km to feed. Isotope analyses of blood samples showed that this distant food across deep waters (0–200 m) is likely to be squid dominated. During the chick rearing period, birds undertook a diet shift to a higher trophic level while foraging closer to their colony, and possibly near river plumes. These findings highlight the need to consider the little penguins’ large potential foraging ranges when managing threats and changes to the environment. [ABSTRACT FROM PUBLISHER]

Occupying about 14% of the world's surface, the Southern Ocean plays a fundamental role in ocean and atmosphere circulation, carbon cycling and Antarctic ice-sheet dynamics. Unfortunately, high interannual variability and a dearth of instrumental observations before the 1950s limits our understanding of how marine-atmosphere-ice domains interact on multi-decadal timescales and the impact of anthropogenic forcing. Here we integrate climate-sensitive tree growth with ocean and atmospheric observations on southwest Pacific subantarctic islands that lie at the boundary of polar and subtropical climates (52-54° S). Our annually resolved temperature reconstruction captures regional change since the 1870s and demonstrates a significant increase in variability from the 1940s, a phenomenon predating the observational record. Climate reanalysis and modelling show a parallel change in tropical Pacific sea surface temperatures that generate an atmospheric Rossby wave train which propagates across a large part of the Southern Hemisphere during the austral spring and summer. Our results suggest that modern observed high interannual variability was established across the mid-twentieth century, and that the influence of contemporary equatorial Pacific temperatures may now be a permanent feature across the mid- to high latitudes. [ABSTRACT FROM AUTHOR]

Occupying 14% of the world's surface, the Southern Ocean plays a fundamental role in global climate, ocean circulation, carbon cycling and Antarctic ice-sheet stability. Unfortunately, high interannual variability and a dearth of instrumental observations before the 1950s limits our understanding of how marine-atmosphere-ice domains interact on multi-decadal timescales and the impact of anthropogenic forcing. Here we integrate climate-sensitive tree growth with ocean and atmospheric observations on southwest Pacific subantarctic islands that lie at the boundary of polar and subtropical climates (52-54˚S). Our annually-resolved temperature reconstruction captures regional change since the 1870s and demonstrates a significant increase in variability from the mid-twentieth century, a phenomenon predating the observational record. Climate reanalysis and modelling shows a parallel change in tropical Pacific sea surface temperatures that generate an atmospheric Rossby wave train which propagates across a large part of the Southern Hemisphere during the austral spring and summer. [ABSTRACT FROM AUTHOR]

The arrival of iceberg B09B in Commonwealth Bay, East Antarctica, and subsequent fast ice expansion has dramatically increased the distance Adélie penguins (Pygoscelis adeliae) breeding at Cape Denison must travel in search of food. This has provided a natural experiment to investigate the impact of iceberg stranding events and sea ice expansion along the East Antarctic coast. As part of the Australasian Antarctic Expedition 2013–14, the Adélie penguin colony at Cape Denison was censused to compare to historic counts. Whilst some 5520 pairs still bred at Cape Denison there has been an order of magnitude decline in Adélie numbers in the area in comparison to the first counts a century ago and, critically, recent estimates based on satellite images and a census in 1997. In contrast, an Adélie population on the eastern fringe of Commonwealth Bay just 8 km from the fast ice edge was thriving, indicating the arrival of B09B and fast ice expansion was probably responsible for the observed recent population decline. In conclusion, the Cape Denison population could be extirpated within 20 years unless B09B relocates or the now perennial fast ice within the bay breaks out. Our results have important implications for wider East Antarctic if the current increasing sea ice trend continues. [ABSTRACT FROM AUTHOR]

The article discusses a study which examines the population of South polar skuas in Cape Denison at Commonwealth Bay, Antarctica in 2013. Findings show the stability of South polar skuas' population based on counts made in 1912, 1913, 1982, 2002 and 2003. It also indicates the lower population density in the region compared with other parts of Antarctica.

This paper presents the first detailed study of the timing and breeding success of an apparently declining population of blue penguins (Eudyptula minor) on the West Coast, South island, New Zealand. Nest contents of 138 natural burrows and 19 nest boxes were determined at regular intervals during the 2006 breeding season. Hatching, fledging, and overall breeding success rates were comparatively high at 78.9, 83.9, and 66.2%, respectively, suggesting that the apparent population decline cannot be explained solely by low breeding success. With 1.18 fledglings produced per pair, productivity was lower than on the east coast of the South island, possibly due to the absence of double clutching. The high incidence of road kills suggests that road traffic may be a major contributing factor to the decline of the blue penguin population in the study area. [ABSTRACT FROM AUTHOR]

Presents results of a monitoring study of three Adélie penguin rookeries at Cape Bird, Antarctica, that was carried out between 1965-87, and, in the light of the results, concludes that it is necessary to be cautious when using bird populations to detect man-induced changes in the marine environment.