Caitlin Kroeger (Department of Ocean Sciences, Long Marine Lab, University of California, Santa Cruz, California, USA) has been awarded a PhD for her thesis on sympatric breeding Campbell Thalassarche impavida and Grey-headed Albatrosses T. chrysostoma during incubation and early-chick-rearing stages on New Zealand’s Campbell Island.

The abstract of her thesis follows:

“The modulation of energy balance through physiological or behavioral adjustments (i.e., allostasis) allows organisms to cope with unexpected challenges, ensuring reproductive success and survival. However, energetic challenges can be exacerbated during critical life stages such as breeding, when more resources are needed to feed offspring. Amphibious marine organisms like seabirds already face a unique challenge of finding patchily distributed ephemeral prey within a vast, dynamic ocean and delivering prey to hungry chicks at land-based nests. With the depletion of ozone and rising sea temperatures, atmospheric and oceanographic disruptions are escalating, affecting the distribution of prey in addition to altering windscapes that seabirds, like the glider-shaped albatrosses, rely on for traveling. Metabolic stress hormones in seabirds can be used to indicate adverse changes within the environment; however, the functional role of stress hormones is confounded by factors such as species, life history, or breeding stage. In chapter 2, I used structural equation models to improve our understanding of the role of corticosterone, a stress hormone, as a mediator of energy balance in two sympatric breeding albatrosses during incubation and early-chick-rearing stages. Campbell (Thalassarche impavida) and grey-headed albatrosses (T. chrysostoma) are annual and biennial breeders, respectively, that occupy differing prey niches. By measuring foraging behavior, mass change, and hormone levels, I found that corticosterone concentrations before and after foraging trips were similar between species and across stages, potentially because of behavioral flexibility or different corticosterone functional roles across stages. However, when parents were provisioning small chicks during the guard stage, the former were more sensitive to changes in energy balance, suggesting that hormone concentrations elicited during this stage are indicative of foraging conditions. Also, pre-trip corticosterone may determine foraging destination in incubation-stage Campbell albatrosses, but it remains unclear if this mediates foraging success. In chapter 3, I examined the role of environmental interactions, behavioral flexibility, and morphological constraints on energy balance during early chick-rearing using the doubly labelled water method to estimate the daily energy expenditure (DEE) of GPS tracked individuals. In both species, greater DEE was associated with greater foraging success, lower mean wind speeds during water take-offs, a greater proportion of strong tailwinds (> 12 ms-1), and younger chick age. Greater foraging success was marginally costlier in male albatrosses of both species and DEE was higher in grey-headed albatrosses when they experienced a greater proportion of strong headwinds. Climate models predict wind speeds will weaken in the foraging range of female Campbell albatrosses and intensify in the range of grey-headed and male Campbell albatrosses, thus breeding costs may increase for both species. In chapter 4, I used a flight cost function to show that mean flight costs were greater during the incubation stage for grey-headed albatrosses, which may interrupt breeding cycles. I then used reanalyzed wind data in combination with bird-borne GPS tracking data to score the cost of flight path trajectory choices and to calculate vector correlation coefficients to evaluate wind-use consistency. Greater wind-use consistency resulted in lower mean flight costs and greater foraging success for both species, but Campbell albatrosses that use low-wind regions had the greatest wind-use consistency. Males of both species gained less mass than females when making similar cost choices during incubation stage transit. Chick-rearing individuals of both species traded greater cost choices for greater foraging success during outbound transit. Overall, foraging strategy, mediated by hormones and morphology, revealed energetic vulnerabilities with respect to species, sex, and breeding stage.”

Note that thesis is “is under embargo until March 20, 2020”.  Access more of Caitlin’s research here.

A Campbell (right) and a Grey-headed Albatross interact on Campbell Island

Reference:

Kroeger, C.E. 2019.  Stress hormones, foraging energetics, and wind-use patterns in two sympatrically breeding southern albatrosses.  PhD thesis.  University of California Santa Cruz.

John Cooper, ACAP Information Officer, 01 November 2019

On 24 September the Centro de Recuperação de Animais Marinhos, Universidade Federal do Rio Grande (CRAM-FURG) received a Northern Giant Petrel Macronectes halli (see below) rescued by the Department of Environment, Santa Vitória Do Palmar, the southernmost municipality in Brazil (click here).

The petrel died during treatment.  During a following necropsy to determine the cause of death a large number of plastic fragments was found in the gastro-intestinal deal tract (see photo below).

CRAM-FURG (Centre for Recovery of Marine Animals) is a hospital dedicated to the rehabilitation of animals, including seabirds, seals and turtles found in Rio Grande do Sul.  The centre reports increasing levels of ingested plastic in treated animals.

Click here to access other posts to ACAP Latest News that describe more cases of giant petrels ingesting plastic objects, as well as latex balloons.

With thanks to Projeto Albatroz, photographs from CRAM-FURG.

John Cooper, ACAP Information Officer, 31 October 2019

Harine Heerah (Centre d'Etude Biologique de Chizé, Villers-en-Bois, France) and colleagues have published in the journal Biological Conservation on tracking Amsterdam Albatrosses Diomedea amsterdamensis, Sooty Albatrosses Phoebetria fusca, Indian Yellow-nosed Albatrosses Thalassarche carteri and Northern Rockhopper Penguins Eudyptes moseleyi at sea from Amsterdam Island in relation to longline fishing effort and marine protected areas.

The paper’s abstract follows:

“In the Southern Ocean, the impact of environmental changes and increasing human encroachment is causing declines in several populations of seabirds.  Amsterdam island (77°33′E; 37°50′S) hosts some emblematic but globally threatened seabird species with alarming population trends. In 2017, concerns about Amsterdam Island's marine biodiversity led to the extension of a marine reserve to the boundaries of the exclusive economic zone (EEZ). Nevertheless, it is unknown whether this protected area is sufficiently large to encompass the most important foraging hotspots of the threatened seabirds, particularly during key stages of their life cycle (e.g. breeding period). We analysed movements of four threatened seabird species using a tracking dataset acquired over several breeding seasons from Amsterdam Island: Amsterdam albatross Diomedea amsterdamensis, sooty albatross Phoebetria fusca, Indian yellow-nosed albatross Thalassarche carteri and northern rockhopper penguin Eudyptes moseleyi. Our objectives were threefold: (1) characterise the at-sea distribution of the above-mentioned populations and delineate the marine Important Bird and Biodiversity Areas (mIBAs) triggered by them; (2) assess the potential threat at-sea by quantifying the overlap between seabird distribution and longline fishing efforts; (3) evaluate the coverage of identified mIBAs by marine protected areas and suggest complementary conservation actions. The identified important areas fell within the boundaries of the EEZ, but vastly exceeded the former reserve. Thus, our results reinforce the justification of the recent expansion of the reserve to the boundaries of the EEZ. However, overall seabird distributions extended beyond the EEZ (5 to 50% of the locations) and we found substantial overlap with longline fishing in the high seas. Our results provide a spatio-temporal envelope of where and when bycatch mitigation and observer coverage of longline fisheries should be mandated and enforced.”

Amsterdam Albatross at sea off Amsterdam Island, photograph by Kirk Zufelt

Reference:

Heerah, K., Dias, M.P., Delord, K., Oppel, S., Barbraud, C., Weimerskirch, H. & Bost, C.A. 2019.  Important areas and conservation sites for a community of globally threatened marine predators of the Southern Indian Ocean.  Biological Conservation 234: 192-201.

John Cooper, ACAP Information Officer, 30 October 2019

The Australasian Seabird Group (ASG) is a special-interest group of Birds Australia, the country partner of BirdLife International.  It was formed in 1971 and is managed in collaboration with the Ornithological Society of New Zealand (Birds New Zealand).  The ASG is a society of seabird researchers, managers and individuals dedicated to the study, enjoyment and conservation of seabirds and their habitats.

Australasian Seabird Group logo: a White-faced Storm Petrel Pelagodroma marina

The Group’s objective is to “promote seabird research and conservation in Australasia”.  This objective is pursued through a range of activities, including publication (from 2010) of a quarterly e-bulletin distributed to members, organisation of symposia on issues affecting seabirds, provision of expert opinion on the management and conservation of seabird populations in Australasia, and the coordination of projects including surveys of seabird islands and beach patrol projects.

The ASG is managed by Executive and General Committees.  Correspondence between ACAP Latest News and several committee members has led to the group lending its support to ACAP’s intention to launch the inaugural World Albatross Day next year on 19 June, the date the Agreement was signed in Canberra, Australia in 2001.  Both Australia and New Zealand are Parties to the Agreement as founding signatories (click here).

The Convener of the ASG’s Executive Committee, Barry Baker has written to ACAP Latest News: “Many albatrosses and petrels are threatened with extinction and only slight increases in the mortality of adults can rapidly reduce populations within a couple of decades.  In a world where there is a focus on the sustainability of extractive industries it behoves fishers and fishery managers to take all necessary steps to reduce the impacts of their activities on non-target species, including seabirds.”

    The ASG’s Secretary, Nicholas Carlile writes as follows: “World Albatross Day is an opportunity to celebrate all that is amazing, humbling and beautiful about this enigmatic group of seabirds.  With so many species close to being lost forever, we must remain vigilant, energetic and forthright in our defence of their survival and ability to flourish in our changing world."

Photo: On Mount Gower, Lord Howe Island, with Vulnerable Providence Petrels Pterodroma solandri overhead

Kerry-Jayne Wilson MNZM who represents New Zealand on the ASG’s General Committee has also expressed her concern: “Albatrosses and other seabirds are under threat, and climate change will further intensify that threat.  Imagine a world without these magnificent birds, is that the legacy we want to leave for generations to come?”

Photo: With King Penguins Aptenodytes patagonicus, Volunteer Point, Fakland Islands (Islas Malvinas)*

ACAP will liaise with the Australasian Seabird Group over the next seven months to raise awareness of World Albatross Day and the plight faced by albatrosses, especially within Australia and New Zealand and in their waters.

Endangered Antipodean Albatross Diomedea antipodensis off Kaikoura, New Zealand; photograph by Kerry-Jayne Wilson

With thanks to Barry Baker, Nicholas Carlile and Kerry-Jayne Wilson

John Cooper, ACAP Information Officer, 29 November 2019

*A dispute exists between the Governments of Argentina and the United Kingdom of Great Britain and Northern Ireland concerning sovereignty over the Falkland Islands (Islas Malvinas), South Georgia and the South Sandwich Islands (Islas Georgias del Sur y Islas Sandwich del Sur) and the surrounding maritime areas.