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

Last week staff of CONAF (Corporación Nacional Forestal) and the NGO Oikonos Ecosystem Knowledge discovered the mutilated corpses of an estimated 300 globally Vulnerable Pink-footed Shearwaters Ardenna creatopus within the National Reserve on Chile’s Isla Mocha.  The remains (mainly wings, heads and legs) were of feathered chicks that had been removed from their burrows.  However, a fire lit against the base of a tree would  also have attracted birds at night as fledging occurs in April and May.

Remains of Pink-footed Shearwaters - and a fire - on Isla Mocha, photographs courtesy of CONAF and Oikonos

“We deeply regret this illegal practice which puts the natural heritage of Chile at risk and [also] the balance of the ecosystem of Isla Mocha.  Oikonos with CONAF make a complaint against those who are responsible for these illegal events that occurred in the early hours of this Thursday [17 May] on Isla Mocha” [in translation].

The Pink-footed Shearwater is an ACAP-listed species (the 31st and most recent to be included within the Agreement) and is a Chilean breeding endemic.  More patrols to deter the illegal take on Isla Mocha have been planned and “legal actions” against those who are responsible are intended. A person has been apprehended and faces charges.

It seems that the poaching of shearwater chicks happens most years within the reserve despite annual patrols in the fledging season, but this year the night-time fire attracted the attention of the police and and a reserve ranger.

With thanks to Verónica López, Oikonos.

John Cooper, ACAP Information Officer, 22 May 2018

The Terres australes antarctiques françaises (TAAF) has applied for the inscription of France’s sub-Antarctic islands (Amsterdam, Crozets, Kerguelen and St Paul) on the List of Natural Sites of UNESCO’s World Heritage Convention (WHC). The nomination file, submitted by France to the WHC in February this year, will be evaluated at the 43rd Session of the World Heritage Committee in July next year.

The French islands were first listed on the convention’s Tentative List in 2016 (click here for the French text for the La Réserve naturelle nationale des Terres Australes Françaises).

Read the announcement in French here and a description of the full nomination process here.

Critically Endangered Amsterdam Albatross Diomedea amsterdamensis - endemic to Amsterdam Island, photograph by Roald Harivel

If the French nomination is successful next year, it will leave only the South Africa’s Prince Edward Islands without World Heritage status in the southern Indian Ocean. Following an unsuccessful nomination, South Africa withdrew its sub-Antarctic islands from its Tentative List.

Click here for a global list of World Heritage sites that support ACAP-listed species.

With thanks to Maëlle Connan.

John Cooper, ACAP Information Officer, 21 May 2018