A Peruvian Diving Petrel chick on Pajaros Uno Island, photograph from Island Conservation

Peruvian Diving Petrels Pelecanoides garnotii have returned to breed on Chile’s Pajaros Uno Island following the eradication of Black Rats Rattus rattus in 2020, confirmed as successful two years later (click here).  Two pairs of have been found breeding this year on the 70-ha island”.  “The audio recordings were played on a specialised solar-powered sound system and during the night when the sea was calm the sounds could be heard up to 300 metres away from the island.”

Pajaros Uno Island, photograph from Island Conservation

The island also supports breeding populations of Peruvian Boobies Sula variegata, Kelp Gulls Larus dominicanus and Humboldt Penguins Spheniscus humboldti.

A Peruvian Diving Petrel at sea, photograph by Island Conservation

The successful eradication effort was undertaken by the Chilean Ministry of the Environment and the environmental NGO Island Conservation.

07 June 2024

Black 24J off Port MacDonnell, South Australia, 5 May 2024, photograph by Hannah Fairbairn

On 5 May 2024 Hannah Fairbairn photographed a great albatross Diomedea spp. at sea while seabird watching on a “pelagic trip” aboard the Jaymar Star of Port MacDonnell Fishing Charters operating out of Port MacDonnell, South Australia to the continental shelf break approximately 30 km offshore, as reported on the Port MacDonnell Seabirds and Pelagics - South Australia Facebook Page.  The bird carried a metal band on its right leg and plastic colour band black 24J on its left.  Read a trip report of the outing here.

Close-up of the Black 24J and metal bands, photograph by Hannah Fairbairn

White lettering on black colour bands is recorded by the New Zealand National Bird Banding Scheme as being used on the Gibson’s subspecies of the Antipodean Albatross D. antipodensis gibsoni on Adams Island in the Auckland Islands group, where Black 24J was banded as a chick on 11 December 2022 by well-known albatross researchers, Graeme Elliott and Kath Walker.  The sighting is apparently the first time the bird has been reported since its banding.

Profile view of Black 24J, photograph by Hannah Fairbairn

In response to a query by ACAP Latest News, Kath writes:

“The photo Hannah took of Black-24J at just over two years old is super interesting as we so rarely see birds of that age and haven’t known the timing of the moult of their juvenile brown feathers.  It looks like they must start moulting their dark brown plumage only 6-12 months after they fledge, when they are 16–22 months old.

We’d assumed this to be the case because the longest time we’ve managed to retain satellite transmitters taped onto the back feathers of juvenile Gibson’s Albatrosses just before they fledge is 16 months (i.e. all the juveniles we tracked had moulted out their original back feathers by 25 months of age).

When Graeme and I banded Black-24J it still had quite a lot of down on its neck and belly so we were unsure whether it was a male or a female. However, at 25 months it already looks so white on the back in the photos we think it’s more likely it is a male.”

 
Another view of Black 24J, with a Shy Albatross Thalassarche cauta in front, photograph by Hannah Fairbairn

 Identification of the five taxa of great albatrosses in the “Wandering Group” at sea in regions where more than one taxon is likely to occur will always be difficult, given the subtle differences in appearance, made harder by gender and age changes in plumage.  Thus, confirming an ID made at sea by the presence of leg bands that have been photographed is both useful for learning how to identify the taxa and to add to knowledge of their at-sea distributions.

With thanks to Hannah Fairbairn and Kath Walker ONZM.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 06 June 2024

Tracks of foraging trips by Light-mantled Albatrosses (LMA) and Sooty Albatrosses (SA) during incubation from multiple colonies across their breeding range. Study colonies indicated by red diamonds.  From the publication

Lily Bentley (Department of Zoology, University of Cambridge, UK) and colleagues have published open access in the Journal of Biogeography on the at-sea distributions of Sooty Phoebetria fusca and Light-mantled P. palpebrate Albatrosses.

The paper’s abstract follows:

“Aim:  Competition is often proposed to drive niche segregation along multiple axes in speciose communities. Understanding spatial partitioning of foraging areas is particularly important in species that are constrained to a central place. We present a natural experiment examining variation in habitat preferences of congeneric Southern Ocean predators in sympatry and allopatry. Our aim was to ascertain consistency of habitat preferences within species, and to test whether preferences changed in the presence of the congener.

Location:  Southern Hemisphere.

Taxon:  Multiple colonies of both species within the genus Phoebetria (sooty albatrosses).

Methods: The two Phoebetria albatrosses breed on islands located from ~37–55°S – sooty albatrosses (P. fusca) in the north and light-mantled albatrosses (P. palpebrata) in the south – with sympatric overlap at locations ~46–49°S. We analysed GPS and PTT tracks from 87 individuals and multiple remotely sensed environmental variables using GAMs, to determine and compare the key factors influencing habitat preference for each species at each breeding colony.

Results:  While foraging habitat preferences are consistent in light-mantled albatrosses, there is divergence of preferences in sooty albatrosses depending on whether they are in sympatry with their congener or in allopatry.

Main Conclusions:  This study represents the most comprehensive work on this genus  to date and highlights how habitat preferences and behavioural plasticity may influence species distributions under different competitive conditions.”

Reference:

Bentley, L.K., Phillips, R.A., Carpenter-Kling, T., Crawford, R.J.M., Cuthbert, R.J., Delord, K., Dilley, B.J., Makhado, A.B., Miller, P.L, Oppel, S., Pistorius, P., Ryan, P.G., Schoombie, S., Weimerskirch, H. & Manica, A. 2024.  Habitat preferences of Phoebetria albatrosses in sympatry and allopatry.  Journal of Biogeography DOI: 10.1111/jbi.14966.

05 June 2024

Osbert Salvin FRS (25 February 1835 - 1 June 1898)

Salvin’s Albatross Thalassarche salvini was named after the 19th Century English ornithologist and entomologist Osbert Salvin FRS by Lord Lionel Walter Rothschild in 1893 (as Thalassogeron salvini sp. nov.).  Rothschild renamed the bird, previously known as the Shy Albatross T. cauta, because “In coloration this species is apparently greyer on the head and neck, the dark loral mark in front of the eye being very conspicuous” (click here and see below).

A Salvin’s Albatross on its nest on the Western Chain, Snares Islands, photograph by Paul Sagar

In 1874 Salvin was appointed as the first Strickland Curator at the University of Cambridge; three years previously he had become editor of the British Ornithologists’ Union (BOU) journal The Ibis, a position he held for a decade  He was a Fellow of the Royal Society, and also of the Linnean, Zoological and Entomological Societies, and at the time of his death was Secretary of the BOU.  The Godman-Salvin Medal, an award instituted by the BOU in 1919 as “a signal honour for distinguished ornithological work”, is named after him and Frederick DuCane Godman.  An interesting connection is that the medal was awarded over a century after Salvin’s death to the well-known albatross researcher and conservationist John P. Croxall CBE, FRS in 2004, who was actively involved with ACAP in its early years and chaired BirdLife International’s Global Seabird Programme.

A signed photograph of Osbert Salvin in his later years

The globally Vulnerable and Nationally Critical Salvin’s Albatross is endemic to New Zealand, where it breeds on the sub-Antarctic Bounty Islands and the Snares Western Chain with an estimated total breeding population of around 52 000 pairs.  Alternative names appearing in the literature for Salvin’s Albatross include Bounty Island Albatross and Grey-backed Albatross (or Mollymawk), although both seem to be little used.Salvin’s Albatross, by Dutch illustrator Johannes Gerardus Keulemans, from A History of the Birds of New Zealand by Walter Buller

This is the second in an occasional series that considers how eponymously named ACAP-listed albatrosses and petrels came to be named.  The first in the series addressed Buller’s Albatross T. bulleri.  The next in the series will be the on Black or Parkinson’s Petrel Procellaria parkinsoni.

Reference:

Rothschild, W. 1893.  THALASSOGERON SALVINI, sp. nov.  Bulletin of the British Ornithologists' Club 1(10): lviii.

John Cooper, Emeritus Information Officer, Agreement on the Conservation of Albatrosses and Petrels, 04 June 2024