(A) Map of Gough Island and relevant features, with an inset map of the 2 study areas (Gonydale and Hummocks) that were cloud-free in the satellite image.  (B) Satellite image (33 cm resolution downsampled to 30 cm resolution) showing GPS coordinates of Tristan albatross nests from ground surveys in 2018, and nests and presumed non-breeders observed in imagery. Three random examples from the satellite image shows an individual nesting Tristan albatross as light pixels in the centre of the panel (from the publication)

Marie Attard (British Antarctic Survey, Cambridge, UK) and colleagues have published in access in the journal Endangered Species Research on attempting to monitor Critically Endangered Tristan Albatross Diomedea dabbenena using satellite imagery.

The paper’s abstract follows:

“The Tristan albatross Diomedea dabbenena is a Critically Endangered species that breeds exclusively on remote islands in the South Atlantic Ocean. Although the population continues to decline, regular on-the-ground monitoring of Tristan albatross populations is logistically challenging and costly. If this monitoring is reduced in the future, then alternative methods would be necessary to track long-term population trends.  Here, we assessed the viability of using 31 cm resolution satellite imagery to count Tristan albatrosses during the breeding season on Gough Island.  Counts of birds in a satellite image by 2 wildlife remote-sensing specialists were compared with GPS coordinates of active nests recorded in the field.  Birds were detected at 103 (67.8%) of the 152 active nests in the cloud-free regions of the satellite image.   Acquiring suitable imagery is challenging because upland nesting sites are prone to low-lying orographic cloud, with only 1 cloud-free image obtained across 8 seasons of archived and 1 yr of tasked imagery. Our research demonstrates that due to incomplete detection, and the limited availability of suitable imagery resulting from persistent cloud cover over the island, Tristan albatrosses cannot be reliably counted or monitored with available satellite imagery.  Differences in detection probability were not explained by nest attributes or bird plumage colouration. More commercial satellites in orbit may improve chances of obtaining cloud-free imagery across the island in the future, but until then, on-the-ground monitoring is required if we are to obtain accurate population counts and for the UK to meet its commitments to monitor this species.”

With thanks to Richard Phillips, Britih Antarctic Survey.

Reference:

Attard, M.R.G., Phillips, R.A., Oppel, S., Bowler, E. & Fretwell, P.T. 2025.  Feasibility of using very high-resolution satellite imagery to monitor Tristan albatrosses Diomedea dabbenena on Gough Island.  Endangered Species Research 56: 187-199.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 11 April 2025

Great Shearwaters at sea, illustration from the Royal Society for the Protection of Birds

Ewan Wakefield (Department of Geography, Durham University, UK) and colleagues have published in the open access journal Marine Ornithology on plumage variation in Great Shearwaters Ardenna gravis.

The paper’s abstract follows:

“Most petrels (family Procellariidae) exhibit little or no obvious variation in plumage with age or sex, either because plumage performs no sexual function or does so in a way poorly perceptible to humans. This limits the inferences that can be made from visual observations of petrels at sea.  However, it has been suggested that nape coloration of Great Shearwaters Ardenna gravis whitens with age.  Here we test this supposition using observations of known-age-class individuals. We necropsied birds bycaught around Gough Island, a major breeding colony in the South Atlantic Ocean, and in Massachusetts Bay, a wintering area off the northeastern coast of the USA, to determine sex and classify nape coloration.  In addition, we classified the nape coloration of adults and fledglings photographed in colonies on Gough Island and Inaccessible Island in the South Atlantic.  Across birds (n = 328), ratios of light:intermediate:dark napes did not differ significantly between age classes, and the accuracy of age classification based on putative nape variation was only 52%.  Nape coloration did, however, vary systematically with sex and location: in Massachusetts Bay, light napes were more prevalent in adult females.  Off Gough Island, where only adults were sampled, this disparity did not occur.  We conclude that while nape coloration may vary due to feather wear, it is not a reliable indicator of age.  Rather, it may perform a sexual function, possibly mediating mate choice.  Further study of plumage variation and behavior at the colony would be required to test this hypothesis.”

Reference:

Wakefield, E.D., Robuck, A. R., Powers, K.D., Ronconi, R.A., Ryan, P.G., & Wiley, D.N. 2025.  Nape coloration varies with sex, not age, among Great Shearwaters Ardenna gravis.  Marine Ornithology 53: 151-158.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 10 April 2025

Amsterdam Island before the fire, photograph by Thierry Micol

ACAP Latest News has previously reported on the January wildfire that caused the evacuation of the personnel manning France’s Amsterdam Island in the southern Indian Ocean.  More information comes from a 15.34-minute video narrated in French and entitled "What will remain of this unique island?".

“This giant fire has been gaining ground for several hours.  And we're on this French base, without a fire station, on one of the most isolated islands in the world...  Lucas is going to immerse us in this true story today.  That of Amsterdam Island, a French island isolated from the rest of the world, home to a handful of people and a unique flora and fauna... all threatened by a giant fire." [Google Translate]

With thanks to Maëlle Connan.

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

Wedge-tailed Shearwaters Ardenna pacifica breed on Raivavae

Vincent Bretagnolle (Centre d’Études Biologiques de Chizé, Beauvoir sur Niort, France) and colleagues have published in the open access journal Marine Ornithology on procellariid seabirds breeding n the French Polynesian island of Raivavae, including three species of shearwaters and five species of gadfly petrels.

The paper’s abstract follows:

“Raivavae is a small island in the Austral Islands of French Polynesia that is surrounded by a lagoon with 28 islets.  Its marine avifauna is one of the least known and least studied in French Polynesia.  Overall, seabird surveys in the various Austral Islands have been extremely sparse.  This study addresses this need, using both historical and recent findings.  The results show high species richness, with 10 breeding procellarid [sic] species, though none are numerous.  We also update the knowledge on breeding petrels from other Austral Islands (except Rapa) and discuss the consequences of these findings in terms of their conservation on an island with cats Felis sp. and rats Rattus sp.”

Reference:

Bretagnolle, V., David, Y., Ghestemme, T., Butaud, J.-F., Withers, T., Shirihai, H. & Thibault, J.-C. 2025.  A petrel breeding diversity hotspot: Raivavae Island (Austral Islands, French Polynesia), with a need for conservation action.  Marine Ornithology 53: 163-171.

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