A well-lit Kaikoura dairy farm as cows wait to be milked before dawn

What seems to be a previously unidentified threat has been reported for the globally Endangered Hutton’s Shearwater Puffinus huttoni, a species endemic to the Kaikoura region of New Zealand’s South Island.  The following text and photographs have been edited from a Facebook post by the Kaikoura Wildlife Hospital.

“This rare nocturnal seabird is disorientated by artificial lighting (streetlights, residential and commercial lighting) along the flight path from the sea to the only two remaining mountain colonies, resulting in crash landing.  Upon nightfall shearwaters fly inland to the Seaward Kaikōura Range and make their way to sea at dawn.

External lighting at milking sheds at dawn results in hundreds of shearwaters crash landing each breeding season, if not thousands.  Most go unnoticed or unreported.  There is also an assumption that being a bird, they will take off again.  Hundreds of shearwaters have been documented circling over milking sheds due to disorientation, with up to 40 shearwaters crash landing at a time.  Once grounded shearwaters are unable to take off without a thermal updraft and require urgent rescue.  Without rescue they succumb to crash landing injuries, cat/dog predation, dehydration, starvation, vehicle strike and cattle trampling.”

A Hutton’s Shearwater rescued from a milking shed where it had been mauled by a cat, causing blindness that required euthanasia

“Capping external lighting, using warm colour temperature light bulbs (amber vs white) and utilising motion sensors where possible, are key to reducing crash landing likelihood at milking sheds.”

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 14 October 2025

A feral cat on Kerguelen Island, with the remains of a European Rabbit, photograph by Charly Gicqueau

NOTE: The English text below has been edited from the original French text, with the help of Google Translate.

The European Union mobilized for the preservation of biodiversity in Kerguelen

The OPACK Project (Optimization of Feral Cat Management Actions in Kerguelen), launched in November 2024, is part of the European Union's BESTLIFE2030 ((Biodiversity and Ecosystem Services in Territories of European Overseas) grant scheme, a fund dedicated to the protection of biodiversity in overseas territories.  Led by the IUCN (International Union for Conservation of Nature), this funding reflects the EU's commitment to fragile ecosystems, such as that of the Kerguelen Archipelago.  Thanks to this support, ambitious actions are being implemented to combat the feral cat, one of the main threats to iconic species such as the globally Vulnerable Wandering Albatross Diomedea exulans.

The feral cat on Kerguelen

In 1951, two cats originating from the mainland France, were introduced to Port-aux-Français on Kerguelen Island to control rodents.  Two other individuals, coming from Madagascar and South Africa, were later brought in 1956.  Soon, these animals escaped from the base and formed a wild population, now estimated at 7000 individuals on the main island, with a density ranging from 0.4 to 2.4 individuals/km².

A major ecological upheaval

The establishment of a population of feral cats has profoundly altered the ecosystem of Kerguelen, particularly through its impact on bird population dynamics.  Indeed, the cats attack both chicks and adult birds of species that were previously not subject to predation.  A striking example: the breeding success of the Wandering Albatross drops to 12% in the presence of cats, compared to 86% in their absence, resulting in an annual population decline of 2.7 to 4.5% each year and threatening its long-term survival.

Baiting a cat trap with rabbit on Kerguelen

Actions and Challenges in the Field

Since 2015, Terres australes et antarctiques françaises (TAAF) have been carrying out targeted actions to reduce the impact of feral cats on three breeding sites of the Wandering Albatross on the Courbet Peninsula (Pointe Morne, Pointe Scott and Ratmanoff). Additionally, interventions occasionally take place on certain islands in the Morbihan Gulf to limit the geographic spread of cats and protect small species, such as the White-headed Petrel Pterodroma lessonii and Slender-billed Prion Pachyptila belcheri, which breed in burrows and are vulnerable to feline predation.  However, the extreme climatic conditions of Kerguelen put both teams and equipment to the test.  After 10 years of effort, the OPACK project (2025) aims to achieve two major objectives: renew trapping equipment and improve cat detection through the use of night vision equipment.

Hope for Many Species

In the long term, these actions are expected to benefit more than 15 species of breeding birds. The challenge is clear: to prevent a collapse of bird populations and to preserve a unique ecosystem.

Click here to read earlier postings to ACAP Latest News on Kerguelen’s feral cats.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 13 October 2025

Sooty Albatrosses on Amsterdam Island, photograph by Jeremie Demay

Camille Schatz (Centre d’Etudes Biologiques de Chizé, Villiers-en-Bois, France) and colleagues have published open access in the ornithological journal Oikos on analysing long-term recapture data sets for four populations of Sooty Phoebetria fusca and Light-mantled P. palpebratq Albatrosses breeding on three French islands in the southern Indian Ocean.

The paper’s abstract follows:

“The variability in responses to environmental change between populations remains poorly quantified and understood.   This shortcoming has major consequences, as variation and flexibility of life-history traits between populations contribute to the estimation of the adaptive potential, which is necessary for predicting the responses of interconnected populations to environmental change.  Here, we use 20–50 years of capture-mark-recapture data from four populations of two closely related species in the southern Indian Ocean, the sooty albatross Phoebetria fusca and the light-mantled sooty albatross Phoebetria palpebrata, to analyze their demographic responses to environmental changes across an oceanic basin scale.  We assessed the role of climate and oceanographic conditions as bottom–up forcings and fisheries bycatch as a top–down forcing on survival and three reproductive parameters in each population.  We found expected demographic responses: negative effects of fishing effort on survival and breeding success, positive effects of wind velocity on breeding success, negative effects of warm sea surface temperature anomalies, and positive effects of sea ice concentration.  Furthermore, our results highlight differences between populations, revealing three main outcomes.  First, the two populations situated at the edge of their distribution seemed more affected by variations in oceanographic conditions than counterparts situated within the core of their ranges.  Second, the two northernmost populations experiencing lower wind speed, had their breeding success affected by meridional wind speed. Third, a large-scale climate index had opposite effects on demographic parameters of the two populations situated in the western and eastern parts of the southern Indian Ocean.  This comparison of the variation in demographic responses to environmental conditions at the inter-population level, sheds light on our limited understanding of the processes that account for life-history trait variation between populations and suggests that local environmental conditions and large-scale climate patterns may drive the diversity of local ecological responses across species' ranges.”

With thanks to Karine Delord.

Reference:

Schatz, C., Delord, K., Joubert, D., Peretou, S., Sun, R. & Barbraud, C. 2025.  Inter-population variation in demographic responses to environmental changes: insights from four seabird populations.  Oikos doi.org/10.1002/oik.11364.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 09 October 2025

WorldView-3 30-cm resolution satellite image of Minami-kojima and Kita-kojima, Senkaku Islands, western North Pacific Ocean on 27 November 2020, with inset showing primary (P) and secondary (S) nest count areas of Short-tailed Albatrosses Phoebastria albatrus; ©2020 Maxar Technologies (read more here)

Morten Frederiksen (Department of Ecoscience, Aarhus University, Roskilde, Denmark) and colleagues have reviewed open access in the ICES Journal of Marine Science technological advances in monitoring seabird populations.

The paper’s abstract follows:

“Monitoring of seabird population size and demography has for decades relied on observer-based methods. While such methods have allowed the accumulation of extensive, standardized time series, while typically involving both volunteer and professional observers, they often suffer from uneven coverage across species and locations, as well as limited replicability. Technological advances, in the form of, for example, visual and/or thermal imagery collected either by permanently situated automated cameras or remote-sensing technology, acoustic data loggers, or automated presence/absence biotelemetry systems, show great potential for overcoming the limitations of observer-based methods and extending coverage of monitoring programmes to more difficult circumstances and species. However, there are challenges and risks associated with the introduction of technology-based monitoring such as initial costs, data storage, post-processing of the large amounts of data, and potential alienation of experienced fieldworkers. We review the issues that agencies responsible for seabird monitoring should consider before introducing technology-based monitoring to complement existing methods, and we provide a set of recommendations and potential future research directions.”

Reference:

Frederiksen, M., Layton-Matthews, K., Bennett, S., Funder Castenschiold, J.H., Cruz-Flores, M., Edney, A.J., Fauchald, P., Franklin, K.A., Guímaro, H.R., Hereward, H.F.R., Johnston, D.T., Merkel, B., Molværsmyr, SW., Sauser, C., Snell, K.R.S. & Humphreys, E.M. 2025.  Opportunities and challenges for new technologies in seabird population monitoring.  ICES Journal of Marine Science, 82, doi.org/10.1093/icesjms/fsaf115.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 08 October 2025