Susan Waugh (Museum of New Zealand Te Papa Tongarewa, Wellington, New Zealand) and Kerry-Jayne Wilson have published open-access in the journal Marine Ornithology on the conservation status of the globally Vulnerable ACAP-listed Westland Petrel Procellaria westlandica, a New Zealand endemic, recommending it be uplisted to Endangered and that its ACAP threat assessment be revised.

The paper’s abstract follows:

“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 Sus 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.”

A Westland Petrel at its breeding site, photograph by Susan Waugh

Reference:

Waugh, S.M. & Wilson, K.-J. 2017. Threats and threat status of the Westland Petrel Procellaria westlandica. Marine Ornithology 45: 195-203.

John Cooper, ACAP Information Officer, 08 November 2017

John van den Hoff (Australian Antarctic Division, Kingston, Tasmania, Australia) has published open access in the journal Marine Ornithology on observations of Southern Giant Petrels Macronectes giganteus at breeding colonies in East Antarctica

The paper’s abstract follows:

“Southern Giant Petrels Macronectes giganteus were leg-ringed as nestlings at two East Antarctic breeding locations, the Frazier Islands and Hawker Island, during the period 1959–1988. I searched these colonies in 2011, deducing ring numbers by using multiple digital photographs. The resightings suggest, but do not confirm, emigration between colonies separated by 1 500 km of coastline. The disparate nature of the ringing program within the Australian Antarctic Territory has led to a loss of important information that could now be used to model and predict how this long-lived species might respond to a number of population pressures, including environmental variability.”

Breeding Southern Giant Petrels on Hawker Island, East Antarctica, photograph by Barbara Wienecke

Reference:

Van Den Hoff, J. 2017. Sightings of ringed Southern Giant Petrels Macronectes giganteus in East Antarctica: a tale of missed opportunity.  Marine Ornithology 45: 191-194.

John Cooper, ACAP Information Officer, 07 November 2017

David Hyrenbach (Hawai'i Pacific University, Marine Science, Waimanalo, Hawaii USA) and colleagues have published in the latest issue of the open-access journal Marine Ornithology on plastic ingestion by Black-footed Albatrosses Phoebastria nigripes foraging to the west of the Hawaiian islands.

“We quantified the incidence (percentage of samples with plastic) and loads (mass, volume) of four plastic types (fragments, line, sheet, foam) ingested by Black-footed Albatross Phoebastria nigripes chicks raised on Kure Atoll, the westernmost Hawaiian colony. All 25 samples contained plastic, mostly in the form of foam and line. On average (± SD), boluses and stomachs contained 28.2 ± 14.3 g and 40.3 ± 29.0 g of plastic, respectively. Plastic was the dominant indigestible material in the boluses and the stomach samples, accounting for 48.8%-89.7% of the bolus mass (mean 67.4 ± 12.1%, median 67.5%, n = 20), and for 18.2%-94.1% of the stomach content mass (mean 70.0 ± 30.3%, median 75.6%, n = 5). Although the ingested plastic fragments ranged widely in size, most (92% in boluses, 91% in stomachs) were mesoplastics (5-25 mm), followed by macroplastics (>25 mm; 7% in boluses, 6% in stomachs), and microplastics (1-5 mm; 1% in boluses, 4% in stomachs). Yet the two fragment size distributions were significantly different, with more small-sized items (3-8 mm) in stomachs and with more large-sized items (46-72 mm) in boluses. To investigate where albatross parents collect this material, we tracked seven provisioning adults during 14 foraging trips using satellite-linked transmitters. The tracked birds foraged west of Kure Atoll (180-150°E, 30-40°N) and spent most of their time over pelagic waters (>2000 m deep; averaging 89 ± 9%), with substantial time over seamounts (averaging 11 ± 7%). Together, these results indicate that Black-footed Albatross chicks at Kure Atoll ingest plastics sourced by their parents foraging in waters of the western North Pacific. Provisioning adults forage within an area of surface convergence, downstream from the Kuroshio Current, and frequently visit seamounts northwest of the Hawaiian archipelago.”

Black-footed Albatross at sea, photograph by Vicki Miller

Reference:

Hyrenbach, K.D., Hester, M.M., Adams, J., Titmus, A.J., Michael, P., Wahl, T., Chang, C.-W., Marie, A. & Vanderlip, C. 2017. Plastic ingestion by Black-footed Albatross Phoebastria nigripes from Kure Atoll, Hawai'i: linking chick diet remains and parental at-sea foraging distributions. Marine Ornithology 45: 225-236.

John Cooper, ACAP Information Officer, 06 November 2017

ACAP held a one-day workshop on gadfly petrels of the genera Pterodroma and Pseudobulweria and other small petrels on 10 September in Wellington, New Zealand, prior to the 10th Meeting of its Advisory Committee (AC10).

The overall objective of the workshop was to advance understanding of the best approaches for international cooperation in the conservation of Pterodroma and other small burrowing petrel species and to prepare a report and recommendations for consideration at the Sixth Session of the Meeting of the Parties to the Agreement (MoP6), due to be held in South Africa in May 2018 (click here to access the workshop's agenda).

Globally Endangered Atlantic Petrel Pterodroma incerta - at risk to introduced House Mice on Gough Island, photograph by Graham Parker/Kalinka Rexer-Huber

The workshop opened with Karen Baird (New Zealand) presenting a commissioned review from BirdLife International entitled “Status, trends and conservation management needs of the Pterodroma and Pseudobulweria petrels” (click here to access the summary). The paper noted that gadfly petrels are a complex group of 39 extant species found in tropical and temperate regions. Many are single-island endemic breeders, often breeding in very remote and inaccessible areas. All are migratory, with records of at least one species in over 100 countries; and occurring as a breeder or resident in 44 countries; 26 species visit 10 or more countries. The review found that of the 39 species almost 67% are globally threatened by IUCN criteria with a further 10% Near Threatened. Fifty-eight per cent of species have a decreasing population trend, eight species have a single subpopulation and seven species have population sizes of less than 250 mature individuals. The review paper was followed by short presentations covering Pterodroma species occurring in the Americas, New Zealand and in Oceania.

Following discussion the workshop supported ACAP increasing its role in international conservation actions for gadfly petrels, and in future perhaps for shearwaters, storm petrels and the remainder of the Procellariiformes.  It was recognised that an increased role was constrained by resources and should be focused on those species that would gain most from international conservation action. Overall these smaller species (both gadfly petrels and others) are affected predominately by land-based threats as opposed to the sea-based threats faced predominantly by the current ACAP-listed species.

The Pterodroma Workshop report (AC10 Doc 14 Rev 1) considered that there is a case for a limited number of additions to ACAP’s Annex 1.  It also noted the need to include social science and sustainable development issues into the design and execution of invasive species eradication projects, especially on inhabited islands.

The report of the workshop was then considered by the Advisory Committee at its 10th Meeting. The recommendations endorsed by the Advisory Committee in regard to the outcomes of the Pterodroma Workshop were as follows as set out in its own report:

1. The Advisory Committee should revisit and complete a revised prioritisation process as soon as possible.

2. Based on this prioritisation and other considerations, Parties may wish to bring forward further species for consideration as additions to Annex 1 of ACAP; the Meeting of Parties might consider whether cases for addition should address the resource needs of such additions.

3. The Secretariat and Parties should improve links to existing international conservation efforts for land-based threats, particularly those working on eradication of invasive species.

4. Encourages the updating of, and possible additions to, ACAP Conservation Guidelines to ensure they adequately cover gadfly petrels and smaller Procellariiformes by the Working Groups.

5. The Population and Conservation Status Working Group and the Secretariat consider ways to improve the profile and uptake of the revised ACAP Conservation Guidelines to highlight that although they are focused on ACAP species, they also cover the smaller Procellariiformes.

6. Explore ways to increase contact with experts on smaller Procellariiformes.

The Committee agreed that the workshop report will form an annex to its own report to the 6th Session of ACAP’s Meeting of Parties, to be held in South Africa next year. It was also agreed that a contact group led by the UK and New Zealand should be established to continue discussions intersessionally regarding Pterodroma and other small burrowing petrels.

The workshop was chaired by Mark Tasker (UK) with John Cooper, ACAP Information Officer acting as rapporteur, with 30 attendees.

John Cooper. ACAP Information Officer, 03 November 2017