Stefan Schoombie (FitzPatrick Institute of African Ornithology, University of Cape Town, Rondebosch, South Africa) and colleagues have published in the journal Antarctic Science on the occurrence of avian pox virus in regionally and globally Vulnerable Wandering Albatrosses Diomedea exulans and regionally and globally Vulnerable White-chinned Petrels Procellaria aequinoctialis at South Africa’s sub-Antarctic Marion Island.

The paper’s abstract follows:

“Albatrosses are among the most threatened groups of seabirds with the main land-based threats being alien invasive species, human disturbance and habitat degradation. Disease outbreaks in Antarctic and sub-Antarctic seabird populations are uncommon, but in the past few decades there has been an increase in reported cases. The sub-Antarctic Prince Edward Islands (46°S, 37°E) in the south-western Indian Ocean provide breeding grounds for many seabird species, including 44% of all wandering albatrosses (Diomedea exulans L.). In 2015, five wandering albatrosses and two penguins (Eudyptes chrysocome Forster and Aptenodytes patagonicus Miller) with pox-like lesions were observed on Marion Island, the larger of the two Prince Edward Islands. Despite intensive study of the wandering albatross population since the 1980s, the only previous records of such lesions are one case in 2006 and another in 2009 in white-chinned petrels (Procellaria aequinoctialis L.). Molecular and phylogenetic analysis of tissue samples from two albatross chicks confirmed the presence of avian pox virus (Avipoxvirus). This highlights the need for research into the diseases present on sub-Antarctic islands, for strict controls to limit the risk of accidental introduction of diseases through human activities and the need for effective conservation measures in the event of an outbreak.”

Wandering Albatross with its chick on Marion Island, photograph by John Cooper

Reference:

Schoombie, S., Schoombie, J., Oosthuizen, A., Suleman, E., Jones, M.G.W., Pretorius, L., Dilley, B.J. & Ryan, P.G. 2017. Avian pox in seabirds on Marion Island, southern Indian Ocean. Antarctic Science https://doi.org/10.1017/S0954102017000347.

John Cooper, ACAP Information Officer, 09 October 2017

Nina O'Hanlon (Environmental Research Institute, University of the Highlands and Islands, Thurso, United Kingdom) and colleagues have reviewed in the journal Environmental Pollution the levels of plastic pollution via entanglement, nest incorporation and ingestion affecting seabirds occurring in the north-eastern Atlantic Ocean. Procellariiform seabirds covered in the paper include the ACAP-listed and Critically Endangered Balearic Shearwater Puffinus mauretanicus (but for which no plastic pollution records were found), along with eight other species of gadfly petrels, shearwaters, a fulmar and storm petrels.

The paper’s abstract follows:

“Marine plastic pollution is an increasing, and global, environmental issue. Numerous marine species are affected by plastic debris through entanglement, nest incorporation, and ingestion, which can lead to lethal and sub-lethal impacts. However, in the northeastern Atlantic Ocean, an area of international importance for seabirds, there has been little effort to date to assess information from studies of wildlife and plastic to better understand the spatiotemporal variation of how marine plastic affects different seabird species. To improve our understanding of seabirds and marine plastic in this region, we completed a synthesis of the published and grey literature to obtain information on all known documented cases of plastic ingestion and nest incorporation by this group. We found that of 69 seabird species that commonly occur in the northeastern Atlantic, 25 had evidence of ingesting plastic. However, data on plastic ingestion was available for only 49% of all species, with 74% of investigated species recorded ingesting plastic. We found only three published studies on nest incorporation, for the Northern Gannet (Morus bassanus) and Black-legged Kittiwake (Rissa tridactyla). For many species, sample sizes were small or not reported, and only 39% of studies were from the 21st century, whilst information from multiple countries and years was only available for 11 species. This indicates that we actually know very little about the current prevalence of plastic ingestion and nest incorporation for many species, several of them globally threatened. Furthermore, in the majority of studies, the metrics reported were inadequate to carry out robust comparisons among locations and species or perform meta-analyses. We recommend multi-jurisdictional collaboration to obtain a more comprehensive and current understanding of how marine plastic is affecting seabirds in the northeastern Atlantic Ocean.”

Balearic Sheawater at sea

With thanks to Alex Bond.

Reference:

O'Hanlon, N.J., James, N.A., Masden, E.A. & Bond, A.L. 2017. Seabirds and marine plastic debris in the northeastern Atlantic: a synthesis and recommendations for monitoring and research, Environmental Pollution. doi.org/10.1016/j.envpol.2017.08.101.

John Cooper, ACAP Information Officer, 06 October 2017

I read Richard Cuthbert’s recently published book on the globally Endangered Hutton’s Shearwater Puffinus huttoni by head torch over two nights in field huts on New Zealand’s Great Barrier Island while tramping the Aotea Track last month after attending ACAP meetings in Wellington. Fitting, I think, as I was on the track to visit the mountain breeding site of another of the country’s endemic burrowing seabirds, the ACAP-listed and globally Vulnerable Black Petrel Procellaria parkinsoni on the upper slopes of Mount Hobson Hirikimata.

New Zealand works hard to look after its many seabird species. The Black Petrel has its champion, Elizabeth ‘Biz’ Bell of the consultancy Wildlife Management International who continues with her annual breeding studies when not eradicating invasive mammals on seabird islands around the world. Hutton’s Shearwater that breeds in mountains inland of Kaikoura on South Island has also had its champions, notably mountain climber Geoff Harrow QSM who discovered its then unknown breeding sites in the Seaward Kaikoura Mountain Range in 1964/65. Years later Geoff helped found the Hutton’s Shearwater Charitable Trust in 2008, of which he is now its patron. The trust rescues and releases fledglings downed by Kaikoura’s street lights and also monitors a fenced sanctuary known as Te Rae o Atiu close to sea level where hand-reared chicks translocated over the period 2005 to 2013 are now returning to breed safe from introduced predators.

In September 1996 English biology graduate Richard Cuthbert, along with a colleague, a field hut and supplies, is dropped off by helicopter in the Kowhai Valley in the Seaward Kaikoura Mountains to commence his PhD research on Hutton’s Shearwater. For three summer seasons Richard works out of the hut in the valley, helped by a number of field assistants, most importantly Erica Sommer, now his wife.  Even Sir David Attenborough drops in for a filming visit!  His PhD is awarded by the University of Otago in 1999 and a suite of eight peer-reviewed publications on Hutton’s Shearwater follows in peer-reviewed  ornithological journals over the next four years.

Richard Cuthbert in a favoured environment: a sub-Antarctic seabird island in the South Atlantic in 2012

Following their field work in New Zealand, Richard and Erica spend a year on Gough Island in the South Atlantic over 2000/01, studying its seabirds that are threatened by House Mice, and over a number of follow-up visits on annual relief voyages, the mice themselves. This essential work has led directly to the welcome (and long-awaited) announcement last month that Gough’s “killer” mice are to be eradicated in 2019 (click here). I have worked with Richard on Gough where I experienced his impressive hill-walking speed while climbing with (well, actually behind) him to a long-term study colony of the globally Critically Endangered Tristan Albatross Diomedea dabbenena in Gonydale - that I set up in 2006. This hill-walking ability was critical to his study of Hutton’s Shearwater, as becomes apparent as one reads his book, launched in September in Kaikoura as the shearwaters return to breed once more.

Seabirds beyond the Mountain Crest is, quite simply, a great read. The author skilfully interweaves the shearwater's known history since its first description and Harrow’s dedicated explorations with evocative accounts of his own field work. Starting with an account of the species’ discovery and naming (and clearing up some mysteries on the way), Richard Cuthbert goes on to describe his first arrival in the Kowhai Valley. Chapters describing field work in all weathers, with the odd climbing outing, follow. Information on the breeding biology of the shearwater is interspersed with encounters of other animals present in the valley. The inquisitive Kea, a mountain parrot is not always welcomed when trying to sleep in the field hut: “…the kea amused themselves by … galloping in unison from one end of the roof to the other…”.

Previously it had been mooted that introduced Stoats were causing low breeding success, loss of colonies and a shrinkage of the shearwater’s population. Richard with Erica’s assistance study the Stoats’ diet (by collecting and dissecting  their scats) and movements by radio-tracking and convincingly show that it is not them but actually predation and habitat destruction by feral pigs that is the primary cause. His surveys find that colonies abandoned since their discovery in the 1960s by Geoff Harrow are all accessible to pigs, whereas the two remaining active colonies are not.  As a consequence control of pig numbers has been undertaken by hunting and trapping near his study colony in the Kowhai Valley.

A Hutton's Shearwater at its mountain burrow entrance, photograph by Richard Cuthbert

 Erica Sommer fits a radio tag to a Stoat, photograph by Richard Cuthbert

The book is nicely set out with a number of half- and full-page colour photos. The science is well explained at the level of the informed layperson without the need for tables and graphs. As a long-term reviewer and editor of scientific works I was pleased to spot no typos from my torch-lit sleeping bag, so well done to the author and to Otago University Press.

Seabirds beyond the Mountain Crest ends with an account of the November 2016 earthquake centred on Kaikoura that has severely impacted at least one of the two mountain colonies (click here). It is not as yet known how many shearwaters that were then in their burrows were killed. Richard Cuthbert writes that he is planning to return to Kaikoura in December to help investigate the situation at the breeding sites.  Let’s hope the news is not all bad, and the shearwater he studied and now has written about so engagingly continues to survive in its mountain haunts.

Book cover from a painting by Austen Deans

With thanks to Richard Cuthbert and Victor Billot of Otago University Press.

Reference:

Cuthbert, R.J. 2017. Seabirds beyond the Mountain Crest. The History, Natural History and Conservation of Hutton’s Shearwater.  Dunedin: Otago University Press. 212 pp. Paperback. 240 x 170 mm.  ISBN 978-0-947522-64-3. NZ$ 45. www.otago.ac.nz/press.

John Cooper, ACAP Information Officer, 05 October 2017

Yusuke Goto (Atmosphere and Ocean Research Institute, The University of Tokyo, Chiba, Japan) and colleagues have published in the journal Science Advanceson a study of GPS tracking data set from globally Near Threatened Streaked Shearwaters Calonectris leucomelas at sea.

The paper’s abstract follows:

“Numerous flying and swimming animals constantly need to control their heading (that is, their direction of orientation) in a flow to reach their distant destination. However, animal orientation in a flow has yet to be satisfactorily explained because it is difficult to directly measure animal heading and flow. We constructed a new animal movement model based on the asymmetric distribution of the GPS (Global Positioning System) track vector along its mean vector, which might be caused by wind flow. This statistical model enabled us to simultaneously estimate animal heading (navigational decision-making) and ocean wind information over the range traversed by free-ranging birds. We applied this method to the tracking data of homing seabirds. The wind flow estimated by the model was consistent with the spatiotemporally coarse wind information provided by an atmospheric simulation model. The estimated heading information revealed that homing seabirds could head in a direction different from that leading to the colony to offset wind effects and to enable them to eventually move in the direction they intended to take, even though they are over the open sea where visual cues are unavailable. Our results highlight the utility of combining large data sets of animal movements with the “inverse problem approach,” enabling unobservable causal factors to be estimated from the observed output data. This approach potentially initiates a new era of analyzing animal decision-making in the field.”

Read a popular account of the study here.

Reference:

Goto^, Y., Yoda, K. & Sato^, K. 2017. Asymmetry hidden in birds’ tracks reveals wind, heading, and orientation ability over the ocean. Science Advances 3(9). DOI: 10.1126/sciadv.1700097.

John Cooper, ACAP Information Officer, 04 October 2017