A White-chinned Petrel is fitted with a tracking sensor; photograph by Richard Phillips

Insights from the second year of a British Antarctic Survey’s study analysing at-sea distributions of White-chinned Petrels Procellaria aequinoctialis from South Georgia (Islas Georgias del Sur)* has revealed significant differences in feeding patterns across breeding sites.

The multi-year study, Spatial Segregation of Seabirds at South Georgia, led by Dr Victoria Warwick-Evans, aims to identify the at-sea distribution and fisheries overlap of birds from different colonies to pinpoint high-risk areas and address bycatch impacts on the species.

Satellite transmitters were fitted to adult petrels incubating eggs in December 2022 at two locations, King Edward Point and Bird Island. The birds’ movement will be tracked until the late chick-rearing phase (when the batteries in the device run out). Early tracking data has revealed birds from King Edward Point and Bird Island travel to similar foraging areas on the Patagonian Shelf and near the Antarctic Peninsula, however, so far only birds from King Edward Point have fed in waters to the north or east of South Georgia.

A map showing the routes of White-chinned Petrels tracked from Bird Island (red) and King Edward Point (green)

“The main aims of the project are to map the at-sea distributions and habitat preferences of birds breeding at different sites across South Georgia, and to identify the fishing fleets that likely pose the highest risk. This increased knowledge will focus conservation and management efforts and help safeguard the future of these globally important seabird populations.” Project leader, Dr Victoria Warwick-Evans

White-chinned Petrels are one of the most frequently killed seabirds in South American fisheries and the majority of those birds comes from breeding populations in South Georgia.

Four species are the focus of the ongoing study: Wandering Albatrosses, Northern Giant Petrels, Southern Giant Petrels and White-chinned Petrels. More information about the project, including an interactive map showing the tracks in near real-time, can be found at the British Antarctic Survey website.

25 January 2023

*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.

A feral pig approaches an incubating Albatross at night, trail camera photograph from the United States Fish and Wildife Service

The Kīlauea Point National Wildlife Refuge, based on the Hawaiian Island of Kauai, has reported on its Facebook page that this season no less than 64 breeding attempts by Laysan Albatrosses Phoebastria immutabilis have failed due to attacks by feral pigs Sus scrofa domesticus.

“We are heartbroken to share that 64 mōlī [Laysan Albatross] eggs were crushed or eaten by pigs on Nihoku beginning on 22 December.  Trail cameras documented the pigs, and we were alerted of the events by our partners the next day.  In collaboration with Pacific Rim Conservation, we mobilized quickly to conduct pig removal, but the damage was already done.  Only three eggs remain on Nihoku, all of which are enclosed in the current 7-acre predator-proof fence.  We have been working on expanding the fenced-in area because we know these specialized fences are highly effective in protecting ground-nesting seabirds from predators, including pigs.”

A Laysan Albatross and its chick in the refuge during the 2020/21 season.  The original Nihoku fence is visible behind, photograph by Jacqueline Olivera

“It is devastating to lose so many eggs just months before the scheduled completion of the new 168-acre [68-ha] perimeter predator-proof fence.  However, it is also assuring to know that next year’s Nihoku colony of nesting mōlī will have over 2 miles [3.4 km] of fence protecting them from future attacks.”

In a follow-up the national refuge writes “Nihokū is the place name for the land between Kīlauea Point and Kāhili, sometimes referred to as Crater Hill.  Located within Nihokū is a 7-acre parcel of land completely enclosed within a predator-proof perimeter fence.  All the eggs in this parcel were protected.  Currently a much larger perimeter fence enclosing all Nihokū is being constructed. All our predated eggs were located inside the uncompleted fence but outside of the old 7-acre protected area.”

The new fence going up, photograph from the Pacific Rim Conservation

As well as attacks by pigs, feral cats Felis catus have killed Laysan Albatross chicks within the refuge in the past (click here).  Domestic dogs Canis familiaris running loose on Kauai have also killed albatrosses from time to time (click here).  The new fence will keep out cats and dogs (and rodents and mongoose), as well as pigs.  Read more about the incomplete predator-proof fence here.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 24 January 2023

The Yelkouan Shearwater Puffinus yelkouan spotted on 10 April 2022 entangled with a disposable COVID-19 face mask (Cyprus, Levantine Sea, and Eastern Mediterranean); photograph by Ioannis Savva

George Karris (Department of Environment, Ionian University, Zakynthos, Greece) and colleagues have published open access in the journal Mediterranean Marine Science on what is thought to be the first sighting of a pelagic seabird entangled in a COVID-19 disposable facemask.

The abstract follows:

“Seabirds are increasingly recognized as important bio-indicators of marine ecosystems that are useful in assessing environmental disturbance on the marine biota. Over the period 2020-22 and during the first national systematic recording of the sea waters surrounding the Republic of Cyprus, we recorded the spatio-temporal presence, abundance and behaviour of seabirds using the  ESAS (European Seabirds At Sea) methodology. Here we present the observation of an accidentally entangled pelagic seabird in COVID-19 material which to the best of our knowledge is the first incident in the Mediterranean Basin. The systematic recording of entangled marine birds in personal protective equipment (PPE) used to prevent COVID-19 transmission worldwide seems to be of crucial importance for one of the most important emerging threats for the conservation of seabirds at global scale.”

Reference:

Karris, G., Savva, I., Kakalis, E., Bairaktaridou, K., Espinosa, C., Smith, M.S., Botsidou, P., Moschous, S., Voulgaris, M.-D., Peppa, E., Panayidies, P., Hadjistyllis, H. & Iosifides, M. 2023. First sighting of a pelagic seabird entangled in a disposable COVID-19 facemask in the Mediterranean Sea. Mediterranean Marine Science, 24(1), 50–55. https://doi.org/10.12681/mms.31918.

23 January 2023

Clockwise from top left: Andean Condor; photograph by Patrick Gijsbers, Black-browed Albatrosses; photograph by Richard Phillips, Southern Caracara; photograph by Rafael Goes

A new study has identified the top native avian predators for the colony of Black-browed Albatrosses Thalassarche melanophris breeding in the inner waters of Tierra del Fuego, Chile. The study, by Daniela Droguett (Ministerio de Medio Ambiente (Ministry of the Environment), Punta Arenas, Chile) and colleagues, has been published in the journal, Polar Biology.

The paper’s abstract: 

“The breeding season is the most vulnerable period in the early stages of the life cycle of seabirds, due to the exposure of their eggs and chicks to the impact by predators. Most of the studies on predator–prey relationships between the Black-browed albatross (Thalassarche melanophrys) and other predators like raptors, were carried out in breeding colonies located in oceanic and highly isolated areas, such as Antarctic islands. However, breeding colonies located in the Sub-Antarctic fjords have not been studied. The geographical position of the study colony makes it susceptible to a wider spectrum of predators than the oceanic islands. Therefore, it is unknown how predation dynamics affect the reproductive success of this species. Here, we show for the first time the identity and activity of avian native predators on the colony in the inner waters of southern Tierra del Fuego, Chile. This study covered seventeen field visits between 2017 and 2020 to monitor the reproductive activity of this colony. In this study, we identified the interaction between predators, the breeding activity and success of albatrosses using direct census and camera traps. Across the study, the number of breeding pairs ranged from 64 (2017) to three (2019) breeding pairs of the Black-browed albatross. Terrestrial birds with occurrence on the colony were the Andean condor, Southern caracara, Chimango caracara and the Turkey vulture. Our results showed that the main avian predator species affecting the breeding success of the Black-browed albatross, were both the Andean condor and the Southern caracara. The Black-browed albatross is a conservation target in this area since of the colony of Islote Albatros is currently part of the Seno Almirantazgo Marine protected area. Therefore, baseline informations on species interactions are fundamental for its management particularly when native predators like the Andean condor are also threatened species globally.”

Reference:

Droguett, D., Arredondo, C., Dougnac, C. et al. 2023. Native avian predators for the world’s Black-browed Albatross (Thalassarche melanophrys) breeding colony in inner waters of Tierra del Fuego, Chile. Polar Biology 46: 77–85 https://doi.org/10.1007/s00300-022-03107-3

20 January 2023