Anne-Sophie Bonnet-Lebrun (Department of Zoology, University of Cambridge, UK) and colleagues have published open access in the journal Marine Biology on individual specialisation in at-sea distribution of satellite-tracked Black-browed Albatrosses Thalassarche melanophris and Grey-headed Albatrosses Thalassarche chrysostoma.

The paper’s abstract follows:

“Many predictive models of spatial and temporal distribution (e.g. in response to climate change or species introductions) assume that species have one environmental niche that applies to all individuals. However, there is growing evidence that individuals can have environmental preferences that are narrower than the species niche. Such individual specialization has mainly been studied in terms of dietary niches, but a recent increase in the availability of individual movement data opens the possibility of extending these analyses to specialisation in environmental preferences. Yet, no study to date on individual specialisation has considered the environmental niche in its multidimensionality. Here we propose a new method for quantifying individual specialisation in multiple dimensions simultaneously. We compare the hypervolumes in n-dimensional environmental niche space of each individual against that of the population, testing for significant differences against a null model. The same method can be applied to a 2-dimensional geographic space to test for site fidelity. We applied this method to test for individual environmental specialisation (across three dimensions: sea surface temperature, eddy kinetic energy, depth) and for site fidelity among satellite-tracked black-browed albatrosses (Thalassarche melanophris) and grey-headed albatrosses (Thalassarche chrysostoma), during chick-rearing at South Georgia. We found evidence for site fidelity in both species and of environmental specialisation among individual grey-headed but not black-browed albatrosses. Specialisation can affect the resilience of populations affected by natural and anthropogenic changes in the environment, and hence has implications for population dynamics and conservation.”

Grey-headed Albatross, photograph by Kirk Zufelt

Reference:

Bonnet-Lebrun, A.-S., Phillips, R.A., Manica, A & Rodrigues, A.S.L. 2018.  Quantifying individual specialization using tracking data: a case study on two species of albatrosses.  Marine Biology doi.org/10.1007/s00227-018-3408-x.

John Cooper, ACAP Information Officer, 07 November 2018

The last rehabilitated Newell’s Shearwater or ʻAʻo Puffinus newelli carrying a back-mounted satellite tag was released to sea from the Hawaiian island of Kauai on 18 October. The release represents the culmination of a project started in 2014 by the Kaua'i Endangered Seabird Recovery Project, the Save our Shearwaters (SOS) programme of the Kauai Humane Society and the U.S. Geological Survey that has resulted in 53 Newell's Shearwaters being tagged since then.  There are currently nine globally Endangered Newell’s Shearwaters transmitting their locations back to the tagging project.  The goal of the project is to compare birds that have been grounded by light pollution on the island and subsequently rehabilitated against wild-tagged 'controls'.

Most of the tagged fledglings this year came from the rugged mountains of the Upper Limahuli Preserve on Kauai.  Following tagging within the preserve chicks were returned to their burrows to fledge naturally.  Three, including the very last one tagged, were “fallout” fledglings that had first been rehabilitated by Save our Shearwaters.  However, over the five years of the project most of the birds satellite-tagged (38) were SOS “rehabs”.  Except for four adults, all those tagged were chicks or fledglings. To date, the longest transmission period recorded  is 111 days, with tagged birds recorded flying thousands of kilometres to the south-west of Kauai.

 A Newell's Shearwater fledgling undergoing rehabilitation is ready for release, with its back-mounted satellite tag in place

 Satellite tags ready for deployment in the Upper Limahuli Preserve

Last of 53!  A rehabilitated Newell's Shearwater fledgling gets released on Kauai's shore.  Note the tag's aerial projecting from the bird's back

André Raine, Kaua'i Endangered Seabird Recovery Project, writes to ACAP Latest News: “we are planning to publish the results after the final transmissions of this season.  This year represents the final cap to the project, so afterwards we can analyse and publish.”

The tagging project has been funded by the St Regis Princeville Resort on Kauai (via Earthjustice and the American Bird Conservancy) and the Kauai Island Utility Cooperative.

 Read more here.

With thanks to André Raine and the KESRP and SOS Facebook pages for information and photographs.

John Cooper, ACAP Information Officer, 06 November 2018

After nearly two years of filming, Kalama's Journey, an attractive eight-minute film produced by talented author and photographer, Hob Osterlund, is now ready for viewing online.  Kalama, a globally Near Threatened Laysan Albatross Phoebastria immutabilis chick on the Hawaiian island of Kauai, became well known by being the subject of a live-streaming “albicam”, hosted and operated by the Cornell Lab of Ornithology.

The video takes the watcher through the hatching, rearing and fledging of an albatross chick reared by an all-female pair.  The audio discusses the problems of sea-level rise and the importance of Kauai’s breeding albatrosses protected from climate change by nesting at altitude on bluff and cliff tops.

One of the female parents incubates Kalama's egg

Kalama as a downy chick, photographs by Hob Osterlund

Watch the video here.

Lastly, pleasant to see that ACAP, and its Information Officer, are both listed in the film’s acknowledgements.

With thanks to Hob Osterlund for information and photographs.

John Cooper, ACAP Information Officer, 05 November 2018

Hannahrose Nevins (American Bird Conservancy, Santa Cruz, California, USA) and colleagues have published online in the open-access journal Marine Ornithology on Laysan Phoebastria immutabilis and Black-footed P. nigripes Albatrosses caught by Alaskan and Hawaiian longline fisheries.

The paper’s abstract in English and Spanish follows:

"In fisheries, incidental bycatch of non-target species, including seabirds, is the result of complex interactions between species and fishing effort. While understanding the magnitude of bycatch is essential to understanding its impact on incidentally caught species, a full characterization requires describing the demographic composition of bycatch and formulating effective mitigation responses. We characterized the body condition, sex, and reproductive maturity of Laysan Albatross Phoebastria immutabilis and Black-footed Albatross P. nigripes collected by fishery observers in the US Alaskan groundfish and halibut fisheries (n = 129: 83 Laysan, 46 Black-footed; 2006-2014) and the US Hawaiian longline fisheries (n = 529: 206 Laysan, 323 Black-footed; 2010-2016). Across species and regions, there was a highly significant bias toward bycatch of sexually mature birds, and most birds were in good body condition. Whereas bycatch in the Alaska region was significantly male-biased for both species, bycatch in the Hawai‘i region was slightly male-biased for Laysan Albatross and moderately female-biased for Black-footed Albatross. Overall, assessment of bycatch demographics across species, regions, and seasons provides valuable information for managers and modelers who assess the impacts of bycatch on wildlife populations.”

“En la pesca, la captura incidental (o bycatch) de especies no objetivo, incluidas aves marinas, es el resultado de interacciones complejas entre las especies y el esfuerzo pesquero.  Si bien la comprensión de la magnitud de la captura incidental es esencial para comprender su impacto en las especies capturadas incidentalmente, una caracterización completa requiere describir la composición demográfica de la captura incidental y formular respuestas efectivas de mitigación. Caracterizamos la composición corporal, el sexo y la madurez reproductiva del Albatros de Laysan Phoebastria immutabilis y el Albatros de Patas negras P. nigripes recolectados por observadores científicos en dos pesquerías de EE.UU: las pesquerías de peces de fondo y Halibut de Alaska (n = 129: 83 Laysan, 46 Patas negras; 2006-2014) y las pesquerías de palangre en Hawái (n = 529: 206 Laysan, 323 Patas negras; 2010-2016). Para las dos especies y regiones estudiadas, se verifico un sesgo altamente significativo por la captura de aves sexualmente maduras, y en buenas condiciones corporales. A pesar que el bycatch en la región de Alaska evidenció un elevado sesgo hacia machos en ambas especies, las de Hawái fueron ligeramente sesgadas hacia machos en los Laysan y moderadamente sesgadas hacia hembras en los de Patas negras. En general, la evaluación de la demografía de la captura incidental a través de especies, regiones y estaciones proporciona información valiosa para los administradores de pesquerías y los modeladores que evalúan los impactos de la captura incidental en las poblaciones de vida silvestre.”

A Black-footed and a Laysan Albatross, photograph from the Kure Atoll Conservancy

Reference:

Nevins, H.M., Beck, J., Michael, P.E./ Hester, M., Peschon, J., Donnelly-Greenan, E. & Fitzgerald, S. 2018. Demographics of Laysan Phoebastria immutabilis and Black-footed P. nigripes Albatross caught as bycatch in Alaskan groundfish and Hawaiian longline fisheries. Marine Ornithology 46: 187-196.

John Cooper, ACAP Information Officer, 02 November 2018