Johanna Wren (Joint Institute for Marine and Atmospheric Research, Honolulu, Hawaii, USA) and colleagues have published in the journal Deep Sea Research Part II: Topical Studies in Oceanography on at-sea sightings of the Near threatened Black-footed Albatross Phoebastria nigripes.

The paper’s abstract follows:

“A serious threat to pelagic seabird populations today is interactions with longline fisheries. While current seabird mitigation efforts have proven successful in substantially reducing seabird interactions in the Hawai‘i-based longline fishery, black-footed albatross (Phoebastria nigripes) interactions have increased. In an effort to better understand when and where these interactions take place, we explore the relationship between black-footed albatross sightings in the Hawai‘i-based deep-set longline fishery and fleet dynamics and environmental variables. Environmental drivers include both large-scale climate variability due to the Pacific Decadal Oscillation (PDO) and El Niño – Southern Oscillation, as well as local oceanographic and atmospheric drivers, such as wind patterns, sea surface temperature, and surface chlorophyll. Using generalized linear models, we found that while season, latitude, and longitude of fishing explained much of the variation throughout the time series, both large scale and local climate variables – positive PDO, strong westerly winds, and cooler sea surface temperatures – explained the increase in black-footed albatross sightings in recent years. Black-footed albatross nest in the Northwestern Hawaiian Islands, and their main foraging habitat while nesting are the productive fronts to the north and east of the Hawaiian Islands. During a positive PDO, a more intense and expanded Aleutian Low shifts westerly winds southward, replacing trade winds in the northern region of the longline fishing grounds. The expanded westerly winds may have two impacts. Firstly, they drive productive surface waters to the south, increasing the overlap of the albatross foraging grounds and the deep-set fishing grounds. Secondly, when westerlies move south, more birds transit through the fishing grounds to the east rather than traveling north to reach the westerlies before traveling eastward north of the fishing grounds. Because the PDO operates on decadal timescales, the high levels of sightings and interactions may persist for many years.”

Black-footed Albatross at sea, photograph by Aleks Terauds

Reference:

Wren, J.L.K., Shaffer, S.A. & Polovin, J.J. 2019.  Variations in black-footed albatross sightings in a North Pacific transitional area due to changes in fleet dynamics and oceanography 2006–2017.  Deep Sea Research Part II: Topical Studies in Oceanography doi.org/10.1016/j.dsr2.2019.06.013.

John Cooper, ACAP Information Officer, 29 July 2019

Raül Ramos (Departament de Biologia Evolutiva, Universitat de Barcelona, Spain) has published in the open-access journal Ecology and Evolution on migration strategies of four different populations of Scopoli's Shearwaters Calonectris diomedea.

The paper’s abstract follows:

“Variability in long‐distance migration strategies is still poorly understood due to the fact that individuals are often tracked from a single colony/population. Transoceanic migrations of Scopoli's shearwaters (Calonectris diomedea) across the Strait of Gibraltar (SoG) have been tracked from several breeding colonies isolatedly, and factors related to the variability in phenological schedules among different populations remain, therefore, not well‐understood. Using light‐level geolocator data, I examined the autumn (postbreeding) and spring (prebreeding) migratory passage dates through SoG of four populations of Scopoli's shearwater spread along the longitudinal breeding range of the species. Additionally, I also estimated the at‐sea activity patterns (from immersion data) during both migratory passages, as well as the body size (from morphometric data) of the individuals of these populations. On average, Scopoli's shearwaters leave the Mediterranean (cross SoG) on 31 October ± 1.8 days on their autumn migrations and return on 03 March ± 1.6 days on their spring migrations. At the population level, there was a clear gradient in the timing of crossing SoG: birds from the westernmost populations (Murcia, SE Spain) were the first ones in leaving the Mediterranean while easternmost breeders (Paximada, Crete) were the last ones. In spring, only birds from the largest breeding population (Zembra, Tunisia) seemed to advance their return and crossed SoG significantly earlier than birds tracked at the remaining populations. In both passages, shearwaters from central and eastern populations spent more time flying than their conspecifics from the western Mediterranean. Scopoli's shearwater populations display a differential phenology and behavior in their migratory passages through SoG. The longitudinal gradient in body size already reported for the species could be an evolutionary response to an obvious trade‐off between sharing common wintering grounds in the Atlantic Ocean and the temporal constraints of restoring physiological condition in those grounds.”

Scopoli's Shearwater at sea, photograph by 'Pep' Arcos

Reference:

Ramos, R. 2019.  Crossing the Pillars of Hercules: understanding transoceanic migrations of seabirds throughout their breeding range.  Ecology and Evolution doi.org/10.1002/ece3.5079.

John Cooper, ACAP Information Officer, 28 July 2019

Raül Ramos (Departament de Biologia Evolutiva, Universitat de Barcelona, Spain) and colleagues have published in the journal Bird Study on the at-sea movements of a juvenile Cory’s Shearwater Calonectris borealis from the Canary Islands.

The paper’s abstract follows:

“Using geolocator-immersion loggers, we tracked for the first time the migration of one Cory’s Shearwater Calonectris borealis fledgling, from its breeding colony in the Canary Islands, and along its first year of life. The juvenile bird initially followed the same migratory path as the adults but visited different areas of the Central and the South Atlantic Ocean.”

Cory's Shearwater at sea, photograph by John Graham

Reference:

Raül Ramos, R., Morera-Pujol, V., Cruz-Flores, M., López-Souto, S., Brothers, M. & González-Solís, J. 2019.  A geolocator-tagged fledgling provides first evidence on juvenile movements of Cory’s Shearwater Calonectris borealis.  Bird Study doi.org/10.1080/00063657.2019.1638341.

John Cooper, ACAP Information Officer, 27 July 2019

Michelle Risi (FitzPatrick Institute of African Ornithology, University of Cape Town, Rondebosch, South Africa) and colleagues have published in the journal Polar Biology on plumage and bill abnormalities in Grey-headed Thalassarche chrysostoma and Light-mantled Phoebetria palpebrata Albatross chicks.

The short note’s abstract follows:

“Accessible colonies of Grey-headed Albatross Thalassarche chrysostoma chicks on Marion Island have been inspected for chicks presenting mouse wounds from 2015, and during these inspections we found several cases of plumage and bill abnormalities. We report on two cases of leucism and three cases of ‘bent-beak syndrome’ in Grey-headed Albatross chicks, and one case of ‘bent-beak syndrome’ in a Light-mantled Albatross Phoebetria palpebrata chick. The leucistic Grey-headed Albatross chicks were found in 2018 and 2019, and both apparently fledged successfully. Three Grey-headed Albatross chicks with deviated upper mandibles were recorded in 2015, 2018 and 2019, and a single Light-mantled Albatross chick with deviated upper mandible was recorded in a study colony in 2014. None of these chicks survived to fledge. These appear to be the first records of leucism for Grey-headed Albatross, and the first records of bill deformities in any albatross species. Although bill deformities may have been overlooked in the past among Grey-headed and Light-mantled Albatrosses at Marion Island, it is worrying that we have had four records in the last few years. Albatrosses have been intensively studied at many colonies for more than 50 years, and we would have expected previous records of the ‘bent-beak syndrome’ if it occurred naturally at low levels, suggesting a novel threat to these seabirds.”

Leucistic Grey-headed Albatross chick - with a normally-plumaged chick behind, photograph by Chris Jones

‘Bent-beak syndrome’ in a Grey-headed Albatross chick, photograph by Peter Ryan

 With thanks to Michelle Risi for information.

Reference:

Risi, M.M., Jones, C.W., Schoombie, S. & Ryan, P.G. 2019.  Plumage and bill abnormalities in albatross chicks on Marion Island.  Polar Biology doi.org/10.1007/s00300-019-02528-x.

John Cooper, ACAP Information Officer, 26 July 2019