Kim Stevens, Vonica Perold and Roelf Daling (suitably masked) after completing an IRATA Level 1 rope access course, required for safety purposes on mountainous Gough

Next month, South Africa will undertake the annual relief of its weather station on the United Kingdom’s Gough Island in the South Atlantic.  The relief is set to take place despite concerns emanating from the COVID-19 pandemic that hampered the annual relief earlier this year of South Africa’s other sub-Antarctic base, on Marion Island in the southern Indian Ocean (click here).

As will be well known to regular readers of ACAP Latest News, Gough Island is both the home of large seabird populations – including of five ACAP-listed species – and of introduced House Mice that have taken to attacking and killing birds, most notably chicks of the Critically Endangered Tristan Albatross Diomedea dabbenena.  Difficulties with international travel due to the pandemic caused the Gough Island Restoration Programme (GIRP) to cancel the intended mouse eradication exercise this austral winter, now intended to be undertaken next year (click here).

A three-person GIRP team (Chris Jones, Alexis Osborne and Michelle Risi) has been on Gough Island for two years, following colour-banded birds in long-term study colonies of Tristan Albatrosses, Atlantic Yellow-nosed Albatrosses Thalassarche chlororhynchos and Southern Giant Petrels Macronectes giganteus and recording the continued depredations by the ‘killer’ mice.  They will be replaced next month by a new team consisting of South Africans Roelf Daling, Vonica Perold (who has previously visited Gough) and Kim Stevens.  Both Kim and Vonica are PhD students at the University of Cape Town’s FitzPatrick Institute of African Ornithology and are experienced field researchers, having spent time studying seabirds on Marion Island.  Kim’s thesis research has been on the foraging ecology and breeding success of the Grey-Headed Albatross Thalassarche chrysostoma on Marion Island.  Vonica is working on temporal and spatial heterogeneity in marine plastic pollution, using seabirds, neuston nets and beach litter for her degree.  They both intend to submit their theses in 2022.

Kim Stevens rests above a Grey-headed Albatross colony on Marion Island

Vonica Perold among Gough’s lowland vegetation during the 2019 relief

Roelf Daling aboard the S.A. Agulhas II on an oceanographic cruise in 2017

The expected sailing date is 17 September on South Africa’s Antarctic research/supply ship, the S.A. Agulhas II.  The field team, along with their fellow G66 expedition members, will be quarantined for two weeks in a government-approved facility in Cape Town before sailing, to reduce the risk of taking the COVID-19 virus to the island.  Kim writes of the quarantine period: “We will be continuing with computer-based training … so we should have enough to keep us busy, but I still have a few projects on the go just in case things are quiet”.  Such as a couple of thesis chapters?

With thanks to Vonica Perold and to Kim Stevens - who can also bake and decorate a mean albicake!

Kim's “Flying Tristan Cake”: a four-layered chocolate cake with coffee buttercream icing in the shape of the world, with a female Tristan Albatross flying over it

John Cooper, ACAP Information Officer, 27 August 2020

Cory's  Shearwater in flight

Joana Calado (Molecular and Environmental Biology Centre, University of Minho, Braga, Portugal) and colleagues have published in the journal Ocean & Coastal Management on Cory's Shearwaters Calonectris borealis (and other seabirds) that interact with Portuguese fishing vessels in the North-east Atlantic.

The paper’s abstract follows:

“Seabirds are marine predators known to forage in association with fisheries, however detailed knowledge on seabird-fishery interactions remains scarce in several regions of the world.  We quantified seabird-fishery interactions and bycatch in central Portuguese coastal waters (NE Atlantic) between 2016 and 2018 in four gears: purse-seines, longlines, gillnets, and fishing traps.  We mapped gear-specific fishing effort and seabird bycatch events and characterized fishery catches.  Specific objectives were to determine separately for seabird-fishery interactions and bycatch (i) the gear with the highest rates, (ii) the most abundant species, and (iii) to assess the main drivers (i.e. year, season, gear, and fishery catch) of seabird-fishery interactions.  Purse-seines had the highest seabird-fishery interactions, and the most abundant species were Yellow-legged and Lesser black-backed gulls, Northern gannet, and Cory's shearwater.  Total seabird-fishery interactions varied inter-annually but not seasonally, indicating high total seabird numbers at fishing boats year-round.  In contrast, higher fishery interactions were found during spring for Yellow-legged gulls. Age classes of individuals varied according to species, and fishery catches had a positive effect on seabird-fishery interactions.  Seabird bycatch occurred mostly in longlines and within the ‘Ilhas Berlengas’ Special Protection Area. Northern gannet and Cory's shearwater were the most bycaught species, and species ecological traits seemed important in determining gear-specific bycatch.  Our results suggest a strong influence of purse-seine and artisanal fisheries on seabirds in the NE Atlantic coast, and future studies should investigate the effects of these fisheries on seabird populations in other regions of the world”.

Reference:

Calado J.G., Ramos, J.A. Almeida, A.,  Oliveira, N., Paiva, V.H.  2020.  Seabird-fishery interactions and bycatch at multiple gears in the Atlantic Iberian coast.  Ocean & Coastal Management  doi.org/10.1016/j.ocecoaman.2020.105306.

John Cooper, ACAP Information Officer, 26 August 2020

Laysan Albatross V301, fledged 2016, seen back in 2020, photograph by Pacific Rim Conservation

V106 as a downy chick during hand rearing in 2015, photograph by Robby Kohley, Pacific Rim Conservation

VI06 back in the refuge, photograph by Megan Dalton, Pacific Rim Conservation

So far, four translocated Laysan Albatross Phoebastria immutabilis chicks have returned to the James Campbell National Wildlife Refuge on the Hawaiian island of Oahu, according to the environmental NGO, Pacific Rim Conservation.  The birds are V106, from the 2015 cohort (out of 10 fledglings) who first returned in 2018 and has been sighted each year since and V301, V309 and V315 from the 2016 cohort (from 19 fledglings) who returned for the first time this year.

The NGO writes “Each now-adult bird was spotted multiple times, and sometimes seen dancing together!  We couldn't be more excited about these birds returning to the predator exclusion fence and look forward to seeing more of them (and hopefully their offspring) in the near future!”

A total of 46 translocated Laysan Albatross chicks fledged from the James Campbell NWR over the three-year period 2015-2017.  Several hundred sightings of Laysans have been subsequently recorded within the refuge. A pair of wild adults has bred in the refuge for the first time, laying an egg in December 2017 (click here).

Translocated Black-footed Albatrosses P. nigripes are also being hand-reared in the James Campbell NWR, as are two other seabird species (click here).

Read more about the seabird translocation projects here.

Information from Pacific Rim Conservation’s Facebook page.

John Cooper, ACAP Information Officer, 25 August 2020

Black-browed Albatrosses gather behind a fishing vessel, photograph by Graham Robertson

Julien Collett and Henri Weimerskirch (Centre d'Etudes Biologiques de Chizé, Université de la Rochelle, Villiers-en-Bois, France) have published open access in the Proceedings of the Royal Society B Biological Sciences on the ability of Black-browed Albatrosses Thalassarche melanophris to memorize where they encountered vessels across consecutive foraging trips from Kerguelen.

The paper’s abstract follows:

“Human activities generate food attracting many animals worldwide, causing major conservation issues. The spatio-temporal predictability of anthropogenic resources could reduce search costs for animals and mediate their attractiveness. We investigated this through GPS tracking in breeding black-browed albatrosses attracted to fishing boats. We tested for answers to the following questions. (i) Can future boat locations be anticipated from cues available to birds? (ii) Are birds able to appropriately use these cues to increase encounters? (iii) How frequently do birds use these cues? Boats were spatially persistent: birds searching in the direction where they previously attended boats would encounter twice as many boats compared with following a random direction strategy. A large proportion of birds did not use this cue: across pairs of consecutive trips (n = 85), 51% of birds switched their foraging direction irrespective of previous boat encounters. Still, 15 birds (27%) were observed to closely approach (approx. 0.1–1 km) where they previously attended a boat while boats were no longer there. This is less than the distance expected by chance (approx. 10–100 km), based on permutation control procedures accounting for individual-specific spatial consistency, suggesting individuals could memorize where they encountered boats across consecutive trips. We conclude albatrosses were able to exploit predictive cues from recent boat encounters but most favoured alternative resources.”

Reference:

Collet, J. & Weimerskirch, H. 2020.  Albatrosses can memorize locations of predictable fishing boats but favour natural foraging.  Proceedings of the Royal Society B Biological Sciences 287.  doi.org/10.1098/rspb.2020.0958.

John Cooper, ACAP Information Officer, 24 August 2020