Susan Waugh (Museum of New Zealand Te Papa Tongarewa, Wellington, New Zealand) and colleagues have published in the journal The Condor: Ornithological Applications on foraging patterns of the ACAP-listed and globally Endangered Westland Petrel Procellaria westlandica.

The paper’s abstract follows:

“Environmental and anthropogenic influences in the marine environment are primary drivers of behavior and demographic outcomes for marine birds. We examined factors influencing the foraging patterns of the Westland Petrel (Procellaria westlandica), a highly threatened, endemic petrel that inhabits subtropical water masses primarily in the Tasman Sea, with a poorly known at-sea distribution. Risk assessments place the species at moderate risk of population impacts from fisheries-related mortality. Studies in the 1990s indicated that trawl fisheries would have an important influence on the Westland Petrel's foraging behavior. We investigated the influence of climatic conditions, marine productivity, bathymetry, the core fishery zone, concurrent fishing activity, light conditions, sex, and breeding stage on Westland Petrel foraging patterns. We analyzed the stable isotopes of carbon and nitrogen from blood sampled during the incubation period and examined changes in isotopic niche width over a 6-yr period. We found that the Westland Petrel's foraging zone varied only slightly between years and that the location of intensively used areas was strongly influenced by bathymetric slope and latitude, and negatively influenced by chlorophyll-a. The core fishery zone had a secondary influence, suggesting that these petrels co-occur with fisheries, but are not dependent on waste for food. Trophic niche width was significantly wider during strong El Niño conditions, indicating that food type, rather than location, was most affected by climatic variation. Consistent use of one marine area across varying times and conditions increases the risk of adverse effects of climate or human-induced impacts on the species. However, marine spatial management tools become viable in these conditions. Further, with rapid increases in sea surface temperatures and extreme values recorded in the region in recent periods, changes to fisheries zones and distributions of natural prey of the species are likely to occur and may change the population's sustainability.”

Westlaand Petrel at sea, photograph by Raja Stephenson

Reference:

Waugh, S.M., Griffiths, J.W., Poupart, T.A., Filippi, D.P., Rogers, K. & Arnould, J.Y.P. 2018.  Environmental factors and fisheries influence the foraging patterns of a subtropical seabird, the Westland Petrel (Procellaria westlandica), in the Tasman Sea.  The Condor 120: 371-387.

John Cooper, ACAP Information Officer, 28 May 2018

Henri Weimerskirch (Centre d’Etudes Biologiques Chizé – Université de la Rochelle, Villiers en Bois, France) and colleagues have published in the journal Polar Biology on albatross numbers on Amsterdam, Crozet, Kerguelen and St Paul Islands.

The paper’s abstract follows:

“Today albatrosses are threatened worldwide, especially by fishing activities, and many populations are currently in decline.  Albatrosses breeding at the French Southern Territories in the south-western Indian Ocean, on the Crozet, Kerguelen and Saint-Paul–Amsterdam island archipelagos, are monitored regularly. This monitoring has been based on a sample of species and sites, and there was a need for an assessment of the population trends for all species at each site. During the past 3 years most populations have been surveyed, allowing an assessment of the trends of albatrosses breeding at the archipelagos of the French Southern Territories over the past 40 years. Wandering Albatrosses show similar trends at all sites within the Crozet and Kerguelen archipelagos, with a recent recovery of colonies after strong declines in the 1970s. Amsterdam Albatrosses are increasing, albeit at lower rates during recent years. Indian Yellow-nosed Albatrosses show a global decline over the entire range. The trends among Black-browed and Grey-headed Albatrosses vary between colonies and archipelagos. Sooty Albatrosses have continuously decreased in numbers whereas Light-mantled Albatross numbers vary considerably between years, with an overall increase over the past 30 years. These results confirm that the French Southern Territories in the southwest Indian Ocean support a significant portion of the world populations of several albatross species. Several species appear to be steadily decreasing probably because of the impact of fisheries and disease outbreaks. The reasons for different trends among populations of the same species are not well understood and require further investigation.”

The crater of St Paul, with La Quille behind, photograph by Jerome Demaine

Reference:

Weimerskirch, H., Delord, K., Barbraud, C., Le Bouard· F., Ryan, P.G., Fretwell, P., Marteau, C. 2018.  Status and trends of albatrosses in the French Southern Territories, Western Indian Ocean.  Polar Biology  doi.org/10.1007/s0030 0-018-2335-0.

albatross bumbes on AmseJohn Cooper, ACAP Information Officer, 25 May 2018

Short-tailed Shearwater at sea, photograph by Peter Ryan

Alan Springer (Institute of Marine Science, University of Alaska Fairbanks, USA) and colleagues have published in the PNAS:

“We have identified a remarkable example of a transhemispheric macrosystem spanning 15,000 kilometers of the Pacific Ocean maintained by a migratory species of seabird that nests in the South Pacific and winters in the North Pacific.”

The paper’s abstract follows:

“Pink salmon (Oncorhynchus gorbuscha) in the North Pacific Ocean have flourished since the 1970s, with growth in wild populations augmented by rising hatchery production. As their abundance has grown, so too has evidence that they are having important effects on other species and on ocean ecosystems. In alternating years of high abundance, they can initiate pelagic trophic cascades in the northern North Pacific Ocean and Bering Sea and depress the availability of common prey resources of other species of salmon, resident seabirds, and other pelagic species. We now propose that the geographic scale of ecosystem disservices of pink salmon is far greater due to a 15,000-kilometer transhemispheric teleconnection in a Pacific Ocean macrosystem maintained by short-tailed shearwaters (Ardenna tenuirostris), seabirds that migrate annually between their nesting grounds in the South Pacific Ocean and wintering grounds in the North Pacific Ocean. Over this century, the frequency and magnitude of mass mortalities of shearwaters as they arrive in Australia, and their abundance and productivity, have been related to the abundance of pink salmon. This has influenced human social, economic, and cultural traditions there, and has the potential to alter the role shearwaters play in insular terrestrial ecology. We can view the unique biennial pulses of pink salmon as a large, replicated, natural experiment that offers basin-scale opportunities to better learn how these ecosystems function. By exploring trophic interaction chains driven by pink salmon, we may achieve a deeper conservation conscientiousness for these northern open oceans.”

Read a popular account of the publication.

Reference:

Springer, A.M., van Vliet, G.B., Bool, N., Crowley, M., Fullagar, P., Lea, M.-A., Monash, R., Price, C., Vertigan, C. & Woehler, E.J. 2018.  Transhemispheric ecosystem disservices of pink salmon in a Pacific Ocean macrosystem.  Proceedings of the National Academy of Sciences of the United States of America  doi.org/10.1073/pnas.1720577115.

John Cooper, ACAP Information Officer, 24 May 2018

Following a taxonomic reassessment, BirdLife International has split Newell’s Shearwater Puffinus newelli into Newell’s Shearwater P. newelli (sensu stricto) and Rapa Shearwater P. myrtae.  The newly defined Newell’s Shearwater breeds on Hawaiian Islands, predominantly on Kaua`i, whereas the Rapa Shearwater is only known to breed on four tiny islets around Rapa, French Polynesia.

Newell's Shearwater, photograph by Eric Vanderwerf

“Both of the newly recognised taxa are under threat from introduced predators, with rats, cats and the mongoose Herpestes javanicus all potentially impacting P. newelli while cats and Polynesian Rats Rattus exulans may be impacting P. myrtae.  Introduced species may also be impacting habitat quality for both species, with habitat alteration by pigs, goats and strawberry guava on Hawaiian islands; while goat grazing may be having an impact on habitat quality for P. myrtae, in addition to anthropogenic land clearance and cultivation.  It is also not only introduced species that have impacted P. newelli. Hurricanes Iwa and Iniki both had a devastating impact on forests of Kaua`i in 1982 and 1992 and the species is heavily impacted by collisions with man-made structures as well as being attracted by artificial lighting”*.

Following an assessment both species have been proposed for a threatened status as globally Critically Endangered.  BirdLife is now calling for comment on the categorizations on its Globally Threatened Bird Forums.

Read more here, including full details of the assessments.  Newell’s Shearwater (sensu lato) is currently categorized as globally Endangered.

Read more ALN postings on Newell’s Shearwaters here.

*quote precised and edited for grammar.

John Cooper, ACAP Information Officer, 23 May 2018