Anton Wolfaardt with the huge Black-browed Albatross colony on Beauchêne Island, South Atlantic, photograph by Leigh Wolfaardt

South Africa’s sub-Antarctic Marion Island is overrun by introduced House Mice Mus musculus, which in the last two decades have taken to attacking and killing the island’s albatrosses and petrels, notably chicks of the globally threatened Grey-headed Thalassarche chrysostoma, Sooty Phoebetria fusca and Wandering Diomedea exulans Albatrosses (click here for previous ACAP Latest News posts on Marion’s mice).

Mice are eating Marion Island's seabirds: a BirdLife South Africa video

The Mouse Free Marion Project is a joint endeavour between the South African Department of Environment, Forestry and Fisheries (DEFF) and the environmental NGO BirdLife South Africa.  A separate entity, the Mouse-Free Marion NPC, has been set up to undertake this important work.  Following a feasibility study in 2013 by New Zealand island restoration expert John Parkes it currently aims to eradicate the mice in 2023.  Last year a call was made for “a highly qualified, dedicated and dynamic” Project Manager to review and refine the Mouse-Free Marion Project and its operational plans and assist with the appointment of the Operations Manager and the eradication team.

Mice attack and kill Grey-headed Albatross chicks on Marion Island, photographs by Ben Dilley and the FitzPatrick Institute

ACAP Latest News is now pleased to report that as of the beginning of the month the appointed MFM Project Manager is South African Anton Wolfaardt, well known to the ACAP community as Co-convenor of its Seabird Working Group (although a position from which he will now stand down to concentrate on the Marion mice).

After spending a year on Marion Island in 1994/95 monitoring its seabirds, Anton completed his PhD at the University of Cape Town (UCT) in 2007 on the impact of oil pollution on the breeding ecology of the now Endangered African Penguin Spheniscus demersus.  He then spent five years in the Falkland Islands (Islas Malvinas)* working for the United Kingdom’s Joint Nature Conservation Committee as the ACAP Coordinator for the South Atlantic including the Falkland Islands, South Georgia and South Sandwich Islands (Islas Georgias del Sur y Islas Sandwich del Sur)*, the Tristan da Cunha -Gough Islands and the UK’s interests in Antarctica.  In recent years Anton has worked as a freelance environmental consultant, as well as as acting as a lecturer and guide on expedition ships to the Antarctic and sub-Antarctic regions during austral summers, along with running a small farm in South Africa’s Eastern Cape with his wife Leigh Wolfaardt – also well known to ACAP for her albatross artwork.

The attempt to eradicate Marion Island’s mice in two years’ time follows on from this year’s attempt to eradicate the House Mice of Gough Island which are also attacking the island’s birdlife by the UK’s Gough Island Restoration Project (GIRP) – as regularly reported by ACAP Latest News.  South Africa, which operates a weather station on Gough, is working closely with GIRP, lending logistic support with transport to and accommodation on the island.  It is envisaged that the ensuing transfer of skills and the donation of equipment will be a major boost to the Marion Island exercise.

Another UCT graduate, Peter Ryan, Director of the FitzPatrick Institute of African Ornithology at the same university, is a member of the Mouse Free Marion Management Committee.  He also Chairs the recently established MFM Scientific and Technical Advisory Group (STAG) which will offer scientific and technical guidance to the management committee as and when required.  The ACAP Information Officer has accepted a request to serve on the STAG.  He looks forward to helping his old colleagues Anton and Peter in helping work towards a mouse-free Marion Island in 2023.

Taking its cue from the successful eradication of mice on New Zealand’s (and far smaller at 21 km²) Antipodes Island by the Million Dollar Mouse project, BirdLife South Africa has been running a ‘Sponsor a Hectare’ campaign to raise funds for the many tonnes of poisoned cereal bait that will be required.  So far 1741 hectares (with a donation of South African Rands 1000 (or USD 90) per hectare) have been sponsored by 657 supporters.  With only 5.73% of the island’s 290 km² funded so far there is a long way to go so your own donation will still be welcomed!

Reference:

Parkes, J. 2014.  Eradication of House Mice Mus musculus from Marion Island: a Review of Feasibility, Constraints and Risks.  BirdLife South Africa Occasional Report Series No. 1.  Johannesburg: BirdLife South Africa.  27 pp.

With thanks to Peter Ryan and Anton Wolfaardt.

John Cooper, ACAP Information Officer, 02 February 2021, reposted 10 February 2021

*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.

Wisdom‘s newest chick shortly after hatching with Akeakamai, Wisdom’s current partner

By now, even irregular readers of ACAP Latest News should have heard of Wisdom, the 70-something Laysan Albatross Phoebastria immutabilis on Midway Atoll.  She is the world’s oldest known wild bird and surely one of the most famous: thought to be at least 70 years of age (she was banded as an adult in 1956 when considered to be not younger than five years old).  The news in now in that her latest egg, laid back in November last year, has hatched as reported last week by the United States Fish and Wildlife Service: Pacific Islands:

“Wisdom, a mōlī (Laysan albatross) and world’s oldest known, banded wild bird, hatched a new chick this week at Midway Atoll.  Biologists first observed the egg pipping on Friday, January 29.  After several days, the chick hatched on Monday, February 1. … Wisdom and her mate, Akeakamai, have been hatching and raising chicks together since at least 2012, when biologists first banded Akeakamai.”

Akeakamai (Red G000) stands over Wisdom’s pipping egg on 30 January. “Pipping is when a young bird begins to crack the shell of the egg when hatching.   Sometimes the process can take multiple days”

Wisdom (Red Z333) returns to tend her chick in the first week of February

Photographs by Jon Brack, Friends of Midway Atoll National Wildlife Refuge

Read more about Wisdom and Akeakamai hatching their latest egg here.

John Cooper, ACAP Information Officer, 09 February 2021

Balearic Shearwater watercolour by Helen Worthington, from a photograph by Pep Arcos

Jessica Phillips (Department of Zoology, Oxford University, UK) and colleagues have published open access in the journal Ecology and Evolution on at-sea observations of Critically Endangered Balearic Shearwaters Puffinus mauretanicus in UK waters.

The paper’s abstract follows:

“Aim.  Europe's only globally critically endangered seabird, the Balearic shearwater (Puffinus mauretanicus), is thought to have expanded its postbreeding range northwards into UK waters, though its at sea distribution there is not yet well understood. This study aims to identify environmental factors associated with the species’ presence, map the probability of presence of the species across the western English Channel and southern Celtic Sea, and estimate the number of individuals in this area.

Location.  The western English Channel and southern Celtic Sea.

Methods.  This study analyses strip transect data collected between 2013 and 2017 from vessel‐based surveys in the western English Channel and southern Celtic Sea during the Balearic shearwater's postbreeding period. Using environmental data collected directly and from remote sensors both Generalized Additive Models and the Random Forest machine learning model were used to determine shearwater presence at different locations. Abundance was estimated separately using a density multiplication approach.

Results.  Both models indicated that oceanographic features were better predictors of shearwater presence than fish abundance. Seafloor aspect, sea surface temperature, depth, salinity, and maximum current speed were the most important predictors. The estimated number of Balearic shearwaters in the prediction area ranged from 652 birds in 2017 to 6,904 birds in 2014.

Main conclusions.  Areas with consistently high probabilities of shearwater presence were identified at the Celtic Sea front. Our estimates suggest that the study area in southwest Britain supports between 2% and 23% of the global population of Balearic shearwaters. Based on the timing of the surveys (mainly in October), it is probable that most of the sighted shearwaters were immatures. This study provides the most complete understanding of Balearic shearwater distribution in UK waters available to date, information that will help inform any future conservation actions concerning this endangered species.”

Reference:

Phillips, J.A., Banks, A.N., Bolton, M., Brereton, T., Cazenave, P., Gillies, N., Padget, O., van der Kooij, J., Waggitt, J. & Guilford, T.  2021.  Consistent concentrations of critically endangered Balearic shearwaters in UK waters revealed by at‐sea surveys.  Ecology and Evolution doi.org/10.1002/ece3.7059.

John Cooper, ACAP Information Officer, 08 February 2021

 Black Petrel  in water colour gouache by Grisselle Chock, from the followimg photograph by Virginia Nicol

Black Petrel at sea, photograph by Virginia Nicol

Elizabeth ‘Biz’ Bell (Wildlife Management International Limited, Blenheim, New Zealand) published in 2016 in the journal Notornis on diving behaviour of the ACAP-listed and globally Endangered Black Petrel Procellaria parkinsoni.

The paper’s abstract follows:

“The black petrel (Procellaria parkinsoni) is recognised as the seabird species at greatest risk from commercial fishing activity within New Zealand fisheries waters. Despite the fact that valuable mitigation information could be obtained from such data, little is known about the diving ability of this species. Diving data were obtained from electronic time–depth recorders from 22 black petrels breeding on Great Barrier Island (Aotea), Hauraki Gulf, New Zealand, during the early chick rearing period from January-February in both 2013 and 2014. This paper presents the first information on the diving ability of black petrels. The deepest dive recorded was 34.3 m, but maximum dive depths varied considerably among individuals (range 0.8-34.3 m). The majority (86.8%) of all dives were < 5 m and black petrels rarely dived to depths of >10 m. The majority (92.7%) of dives were during the day and time of day had no major effect on dive depth. Only males dived at night, between 2300 and 0200 hours. This information could be used to improve mitigation measures for black petrel and other seabird bycatch in longline fisheries particularly in relation to recommended depths for unprotected hooks and line sink rates. To achieve the recommended minimum 10 m depth for unprotected hooks it has been shown that hooks have to be deployed at 6 knots with a 0.3 m/second line sink rate when using 100 m streamer lines. Adoption of these measures should further reduce black petrel bycatch in longline fisheries.

With thanks to Biz Bell, Grisselle Chock  and Virginia Nicol.  Note that ACAP Latest News missed featuring this paper when it was published.  It is posted now because of its importance for conserving the now nationally and globally Endangered species.

Reference:

Bell, E.A. 2016.  Diving behaviour of black petrels (Procellaria parkinsoni) in New Zealand waters and its relevance to fisheries interaction.  Notornis  63: 57-65.

John Cooper, ACAP Information Officer, 05 February 2021