(a) Kapiti Island (with Weka, shown in blue) and Mana Island (without Weka, shown in yellow) alongside their Tītī (Sooty Shearwater) colonies (black stars). (b) Camera trap screenshots of Weka predating on Tītī chick on Kapiti Island. (c) Cumulative percentage of hatched Tītī chicks predated by Weka on Kapiti Island in 2025 (from the publication)

Hailley Danielson-Owczynsky (Department of Coastal Systems, Royal Netherlands Institute for Sea Research, ‘t Horntje, Netherlands) and colleagues have published open access in the international journal of avian science Ibis on the declining fortunes of Sooty Shearwaters Ardenna grisea on an island with no non-native mammalian predators but facing depredation of chicks by native Weka Gallirallus australis.

The paper’s abstract follows:

“Seabirds play key ecological roles but face increasing threats worldwide. Among them, Tītī (Sooty Shearwater) Ardenna grisea are among the most abundant and culturally significant species in the Southern Hemisphere but are also threatened. Kapiti Island, Aotearoa (New Zealand), holds a Tītī colony which, despite eradication of non-native mammalian predators, continues to decline. Key drivers are changing oceanic conditions and depredation of chicks by Weka Gallirallus australis (a native rail). A neighbouring island, Mana Island, also holds a Tītī population, but no Weka, offering a natural ‘control’ site. Despite the decline of Tītī on Kapiti, and wider Aotearoa, and their ecological and cultural importance, few comprehensive estimates of vital rates exist (i.e. synthesized from multiple disparate data streams to mitigate uncertainty). We fitted data collected from Tītī at both Mana (1991–2025) and Kapiti (2022–2025) Islands to an integrated population model (IPM) to estimate vital rates and population size and to project the Kapiti population under two scenarios: status quo and a counterfactual ‘no Weka’ scenario informed by productivity estimates from Mana. Adult annual survival was estimated at 0.900 (95% CI 0.875–0.920), immature (i.e. prior returning to the colony as an adult, which peaked at ages 6–7) survival at 0.776 (0.735–0.816), breeding probability at 0.807 (0.723–0.879), breeding success on Kapiti (Weka) at 0.019 (0.005–0.043), breeding success on Mana (no Weka) at 0.420 (0.374–0.468) and adult population size on Kapiti at 237 (147–313). Without effective intervention, projections from 2025 predict a 70% decline in the Kapiti population by 2050 (𝜆 = 0.953; 0.848–1.00). However, counterfactual projections still show ongoing, albeit slower, declines (𝜆 = 0.969; 0.875–1.000), suggesting other pressures in addition to Weka predation. Our findings support future decision-making for conservation management on Kapiti, highlight the need for action beyond the island to address external stressors, and bear relevance to seabird and Weka management throughout Aotearoa to protect the iconic Tītī.”

Reference:

Ossona De Mendez, E., Dunphy, B.J., Cain, K.E., Chambon, J., Cotter, R., Daigle, E., Taylor, G.A. & Fischer, J.H. 2026.  Counter-factual simulation highlights requirements for additional management to avert extinction of a relict Tītī/Sooty Shearwater population.  Ibis doi.org/10.1111/ibi.70088.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels 28 July 2026

 Graphical abstract from the publication*

William Mills (Department of Geography and Environmental Science, University of Reading, UK) and colleagues have published open access in the journal Environmental Pollution on mercury levels in the feathers of chicks of eight procellariiform species breeding on Bird Island, South Georgia (Islas Georgias del Sur)* in the South Atlantic Ocean.

The paper’s abstract follows:

“At the subantarctic islands of South Georgia, albatrosses and petrels occupy a range of trophic niches, from zooplanktivore to top predator. Interspecific variation in mercury (Hg) contamination is therefore expected to be large within this community, as diet is the main exposure pathway. This study compared total Hg (THg) concentrations and stable isotopes of carbon (δ¹³C) and nitrogen (δ¹⁵N) in feathers of >250 chicks belonging to eight albatross and petrel species at South Georgia during three years (2018-2020). Generally, zooplanktivorous species (Antarctic prion Pachyptila desolata, blue petrel Halobaena caerulea) and the wandering albatross Diomedea exulans (top predator) were least and most contaminated, respectively. However, the order of increasing THg concentrations among giant petrels Macronectes spp. and pelagic generalist species varied annually, likely reflecting shifts in diet or distribution given the diversity of alternative foraging habitats. Accounting for species effects, THg was positively associated with δ¹⁵N in all years, and with δ¹³C in two years, indicating that contamination increased with trophic position and generally, but not always, varied along a foraging habitat or latitudinal gradient. Lastly, pelagic generalists and northern giant petrels M. halli, but neither zooplanktivores nor wandering albatrosses, were more contaminated at Kerguelen than South Georgia, potentially reflecting dietary differences, more complex food chains and a reduced role of Antarctic krill Euphausia superba in the pelagic foodweb of the southern Indian Ocean. Overall, this study highlights the drivers of variation among species, years and regions in THg concentrations, and the need for further work to predict future trends.”

Click here and here to access two previous papers on mercury in South Atlantic procellariiform seabirds by William Mills.

With thanks to Richard Phillips.

Reference:

Mills, W.F., Bustamante, P. & Phillips, R.A. 2026.  Dynamics of mercury contamination within the albatross and petrel community at South Georgia.  Environmental Pollution 406, 128745.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 27 July 2026

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

The British Ornithologists’ Union (BOU) will hold is 2027 Annual Conference in| Nottingham, UK (and virtually) over 6-8 April 2027.  The theme will be Avian Disease Ecology: Combining Avian Ecology and Onehealth to Understand and Mitigate Disease. 

“The ongoing avian influenza pandemic has devastated wild bird populations across the globe and exemplifies the urgency of advancing our understanding of disease ecology in wild birds.  In addition to highly infectious viral pathogens like avian influenza, birds face constant exposure to a diverse suite of parasites and pathogens which are increasingly recognised as having considerable impacts on bird behaviour, demography and extinction risk”

One of the keynote lectures will be given by Thierry Boulinier (Director of Research, Centre d’Ecologie Fonctionnelle et Evolutive, France) with the title “High pathogenicity avian influenza in seabirds: the benefits of integrative approaches”

Submit your abstract for a talk, poster or Bluesky-only presentation by 31 July 2026 from here.  Conference registration will open in November 2026.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels 25 July 2026

Chris Jones takes a rest on Grey-headed Albatross Ridge, Marion Island, photograph by Michelle Risi

Chris Jones is a PhD student at the FitzPatrick Institute of African Ornithology at South Africa’s University of Cape Town.  Following a decade of seabird research on both sub-Antarctic and tropical oceanic islands in the Atlantic and Indian Oceans carried out with his wife and fellow PhD student, Michelle Risi, he has now commenced his doctoral study on how breeding-site climate may affect surface-nesting albatrosses on sub-Antarctic Marion Island.  Below, Chris describes his thesis research to ACAP Latest News

A Grey-headed Albatross chick pants to cool down on Marion Island, photograph by Chris Jones

“Unlike burrowing petrels, which nest underground, these large seabirds incubate their eggs and raise their chicks on the surface, exposed to wind, rain, cold and, increasingly, warmer conditions.  The FitzPatrick Institute’s Hot Birds Research Project, co-led by the institute’s Director, Associate Professor Susan Cunningham, is investigating how changing climate at breeding sites may affect these iconic Southern Ocean seabirds.  The project combines long-term seabird monitoring with direct observations, miniature weather stations, black-bulb temperature loggers that represent the heat load experienced by birds, nest-site measurements and fine-scale microclimate modelling.  Together, these approaches will help show how weather affects breeding outcomes, where colonies may be most exposed, and which parts of the Marion Island landscape may provide safer refuges as the climate changes.”

Grey-headed Albatross Ridge in midsummer on Marion Island, photograph by Chris Jones

Chris continues: “As part of the Hot Birds project, my PhD is focused mainly on albatrosses, particularly the Endangered Grey-headed Albatross Thalassarche chrysostoma which breeds on steep ridges on Marion Island.  Preliminary results suggest that where a chick sits on the slope matters.  Nests higher up the east-facing Grey-headed Albatross Ridge are warmer than those lower down, because the lower tiers are shaded earlier in the day.  Chicks in the upper part of the colony appear less likely to survive when daily maximum air temperatures rise above about 14–16°C, whereas chicks lower down the slope seem less affected, likely because they experience a shadier microclimate.  I will investigate which air temperatures, heat-load conditions and weather patterns are linked to thermoregulatory behaviours such as panting, and whether these conditions predict breeding failure.  I will also test how well microclimate models reproduce field-measured temperature and humidity, map areas of potential climate exposure and refuge across breeding habitats and assess how breeding-site climate exposure could affect the long-term population dynamics of Grey-headed Albatrosses.  A further part of my PhD will examine whether nest-scale microclimate affects breeding outcomes in Marion’s winter-breeding Vulnerable Wandering Albatrosses Diomedea exulans.”

Chris’ PhD research is being supervised by Susan Cunningham, Emeritus Professor Peter Ryan (former Fitztitute Director) and Dr Shannon Conradie, a Senior Lecturer in the School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, and long-term member of the Hot Birds Research Project team.

Avumile Bawuli on Marion Island with a black-bulb temperature logger used to estimate operative temperature - the thermal conditions experienced by a bird - on an empty nest

Also part of the Fitztitute’s Hot Birds Research Project is Avumile Bawuli, who overwintered on Marion Island in 2025/26 and is expected to begin his Master’s degree in 2027.  His work will focus on giant petrels Macronectes spp. that breed on Marion Island’s open slopes and coastal plains.  Avumile will investigate how air temperature and the temperature experienced at the nest relate to the body temperature of giant petrel chicks, helping to identify when chicks are able to maintain safe body temperatures and when they may begin to experience heat stress.  He will also investigate chick hydration, testing to what extent warmer conditions increase the risk of dehydration.  A second part of his project will focus on Northern Giant Petrels M. halli, comparing current nest-site measurements with data collected in the same colonies in 2003 by John Cooper and Nico de Bruyn (but never published).  This will allow him to ask whether nest-site use has changed over the past two decades, and whether particular nest features, such as shelter from prevailing weather provided by protruding rocks, are linked to breeding success.

A Northern Giant Petrel nest next to a rock on Marion Island showing a black-bulb temperature logger and a reader used to record the body temperature of the chick that has been fitted with a PIT-tag thermometer, photograph by Avumile Bawuli

Together, Chris and Avumile’s research will help explain how changing weather on Marion Island may affect surface-nesting seabirds, from the scale of the bird and nest to the colony and, ultimately, the population.

With thanks Susie Cunningham.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 22 July 2026