From ship to shore: unloading rodenticide bait by helicopter; photograph from Tony Martin

Watch a recent video (webinar) that describes the successful eradication of rats and mice on South Georgia (Islas Georgias del Sur)* in the South Atlantic by its Project Leader.

“Find out what it was really like running the world's largest rodent eradication project in one of the most remote and challenging environments in this webinar that was recorded on 27 July 2022.  Project Leader, Professor Tony Martin, explains how he permanently had a knot of anxiety in his stomach for months at a time during the multi-year Habitat Restoration Project as he grappled with the uncertainties of the project. In this free online presentation, Tony tells us about the monumental heroics of ‘Team Rat’ to make the Habitat Restoration Project a historic success.

South Georgia [Islas Georgias del Sur*] has been free of rodents for a few years now, and Tony has had a chance to recover and reflect on the Habitat Restoration project.  He tells us about some of the lesser-known stories from behind the scenes.  The eradication was declared a success in 2018, and we also hear from Ecologist Alastair Wilson about some of the changes to the wildlife happening on the island since the rodents have gone.  And with his experiences of living in one of the few areas that were always rat-free, he describes how [the island] should be in the future once all the populations have fully recovered.”

Areas baited over three separate years, 2011-2015

John Cooper, ACAP Information Officer, 02 August 2022

*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.

 
Common Diving Petrel, by Johannes Gerardus Keulemans, 1842-1912

Aymeric Fromant (School of Life and Environmental Sciences, Deakin University, Burwood, Australia) and colleagues have published open access in the journal Oecologia on niche segregation in the Common Pelecanoides urinatrix and the South Georgian P. georgicus Diving Petrels.

The paper’s abstract follows:

“Niche theory predicts that to reduce competition for the same resource, sympatric ecologically similar species should exploit divergent niches and segregate in one or more dimensions. Seasonal variations in environmental conditions and energy requirements can influence the mechanisms and the degree of niche segregation. However, studies have overlooked the multi-dimensional aspect of niche segregation over the whole annual cycle, and key facets of species co-existence still remain ambiguous. The present study provides insights into the niche use and partitioning of two morphologically and ecologically similar seabirds, the common (CDP, Pelecanoides urinatrix) and the South Georgian diving petrel (SGDP, Pelecanoides georgicus). Using phenology, at-sea distribution, diving behavior and isotopic data (during the incubation, chick-rearing and non-breeding periods), we show that the degree of partitioning was highly stage-dependent. During the breeding season, the greater niche segregation during chick-rearing than incubation supported the hypothesis that resource partitioning increases during energetically demanding periods. During the post breeding period, while species-specific latitudinal differences were expected (species specific water mass preference), CDP and SGDP also migrated in divergent directions. This segregation in migration area may not be only a response to the selective pressure arising from competition avoidance between sympatric species, but instead, could reflect past evolutionary divergence. Such stage-dependent and context-dependent niche segregation demonstrates the importance of integrative approaches combining techniques from different fields, throughout the entire annual cycle, to better understand the co-existence of ecologically similar species. This is particularly relevant in order to fully understand the short and long-term effects of ongoing environmental changes on species distributions and communities.

This work demonstrates the need of integrative multi-dimensional approaches combining concepts and techniques from different fields to understand the mechanism and causal factors of niche segregation.”

Reference:

Fromant, A., Arnould, J.P.Y., Delord, K., Sutton G.J., Carravieri, A., Bustamante, P., Miskelly, C.M., Kato, A.,  Braut-Favrou, M., Cherel, Y. & Bost, C.-A. 2022.  Stage-dependent niche segregation: insights from a multi-dimensional approach of two sympatric sibling seabirds.  Oecologia 199: 537-548.

John Cooper, ACAP Information Officer, 01 August 2022

Editorial Note:  ACAP Latest News usually restricts its news posts to matters pertaining to the biology and conservation of the 31 species of ACAP-listed albatrosses and petrels and those procellariiform genera of particular interest to the Agreement, mainly gadfly petrels Pterodroma spp. and shearwaters Ardenna, Calonectris and Puffinus spp.  In the case of the post above, diving petrels Pelecanoides spp. are not usually featured in ALN but the topic of niche segregation should be of interest and relevance to those studying closely related and sympatric species of ACAP-listed birds, such as the mollymawk albatrosses Thalasssarche and the giant petrels Macronectes spp.

The beached Light-mantled Albatross, Rameswaram Island, Tamil Nadu, India; photograph by Francis Aravind

A short communication published in the Journal of Threatened Taxa by H. Byju (Centre of Advanced Study in Marine Biology, Annamalai University, Parangipettai, Tamil Nadu, India) and N. Raveendran reports the first record of a Light-mantled Albatross Phoebetria palpebrata (Near Threatened) from India, and as the text states, for the whole Oriental Region.

The albatross was found and photographed alive, “quite frail, may be dehydrated, and unable to fly”, on Anthoniyapuram Beach, Rameswaram Island, Tamil Nadu on 8 September 2020.  After a level of care, which included an attempt to feed it, the albatross was released back to sea.

This is not the first record for this high-latitude Southern Ocean species crossing the equator into the northern hemisphere.  An earlier record is of a bird photographed off central California, USA in July 1994 (click here).

Read a popular account of the scientific publication.

With thanks to Jaimie Cleeland, Australian Antarctic Division.

References:

Byju, H. & Raveendran, N. 2022.  First Asian record of Light-mantled Albatross Phoebetria palpebrata (Foster, 1785) from Rameswaram Island, Tamil Nadu, India.  Journal of Threatened Taxa 14: 21473–21475.

Stallcup, R, & Terrill, S.1996.  Albatrosses and Cordell Bank.  Birding 28: 106-110.

John Cooper, ACAP Information Officer, 29 July 2022

The Bird Island Wandering Albatross on Kerguelen

A male Wandering Albatross Diomedea exulans (Vulnerable) bearing UK (British Museum) metal band No. 4004249 on its left leg was photographed near Lac Marville, Courbet Peninsula, Kerguelen Archipelago in the southern Indian Ocean on 31 January 2022 by French research volunteer Kevin Guille.  The adult bird was first seen on its own in the Wanderer monitoring colony on the Courbet Peninsula, in the framework of the project “Seabirds and Marine Mammals as Sentinels of Global Change in the Southern Ocean” (Project: 109 ORNITHOECO) supported by the French Polar Institute Paul Emile Victor).  The bird was then involved in courtship behaviour with an arriving female Wanderer.

A view of the Courbet Peninsula monitoring colony; photographs by Kevin Guille

Following an enquiry by Karine Delord (Centre d'Etudes Biologiques de Chizé, France), Andy Wood of the British Antarctic Survey replied that Wandering Albatross 4004249 was banded as a chick at Bird Island, South Georgia (Islas Georgias del Sur)* in the South Atlantic on 28 September 2009, making it a 12-year-old when resighted by Karine and her colleagues.  Andy also confirmed that after banding the bird has not been seen back on Bird Island.

This is the first time that an interchange of a Wandering Albatross between Bird Island and Kerguelen has been recorded, although there have been a few movements both ways between the French Crozet Islands (farther to the west from Kerguelen) and the South Atlantic island.  Very few records exist of movements between Kerguelen and the South African Prince Edward Islands in the southern Indian Ocean, although there are many interchanges between the Ile de la Possession, Crozet and the Prince Edwards, approximately 1000 km apart.

With thanks to Maëlle Connan, Karine Delord, Richard Phillips and Andy Wood.

Reference:

Cooper, J. & Weimerskirch, H. 2003.  Exchange of Wandering Albatrosses Diomedea exulans between the Prince Edward and Crozet Islands: implications for conservation.  African Journal of Marine Science 25: 519-523.

John Cooper, ACAP Information Officer, 28 July 2022

*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.