Sebastian Jiménez (Laboratorio de Recursos Pelágicos, Dirección Nacional de Recursos Acuáticos, Montevideo, Uruguay) and colleagues have published in the journal Animal Conservation on differences in survival rates between male and female Wandering Albatrosses Diomedea exulans.

The paper’s abstract follows:

“The population of wandering albatrosses Diomedea exulans at South Georgia is decreasing because of bycatch in longline fisheries.  Until at least the early 1990s, the survival rate of females was lower than males, consistent with the adult female-biased bycatch reported for fisheries operating around the Brazil-Falklands Confluence (BFC).  Here we use extensive tracking data (1990–2012) from breeding birds at South Georgia to investigate overlap with longline fishing effort reported to the International Commission for the Conservation of Atlantic Tunas (ICCAT).  Using data from multiple years, we conclude that breeding females are at higher risk than males from all the main pelagic longline fleets in the south-west Atlantic.  Our overlap index (based on fishing effort and bird distributions) correlated positively with numbers of ringed birds reported dead on longliners, indicating that the metric was a good proxy of bycatch risk.  The consistent sex bias in overlap across years, and the likely resulting sex-biased mortality, could account for lower adult female survival rate at the colony.  The risk from fisheries changed seasonally; both sexes overlapped with pelagic longline effort during incubation (January–March), and particularly during post-brood chick-rearing (May–December), whereas overlap was negligible during brooding (April).  The highest percentage of overlap was with the Taiwanese fleet, then vessels flagged to Brazil, Uruguay, Spain, Japan and Portugal.  Females were consistently at greatest risk in the BFC region, whereas males showed lower and more variable levels of overlap with fisheries from 35 to 45°S.  Our results have important implications for management of ICCAT longline fisheries and conservation of this highly threatened albatross population.”

Wandering Albatross at sea in the South Atlantic, photograph by John Chardine

Reference:

Jiménez, S., Domingo, A., Brazeiro, A., Defeo, O., Wood, A.G., Froy, H., Xavier, J.C. & Phillips, R.A. 2015.  Sex-related variation in the vulnerability of wandering albatrosses to pelagic longline fleets.  Animal Conservation DOI: 10.1111/acv.12245.

John Cooper, ACAP Information Officer, 06 November 2015

Junichi Sugishita (Department of Zoology, University of Otago, Dunedin, New Zealand) and colleagues have published in the open-access journal Global Ecology and Conservation on at-sea tracking of Northern Royal Albatrosses Diomedea sanfordi feeding chicks in relation to the presence of fishing vessels.

The paper’s abstract follows:

“Incidental fisheries bycatch is recognised as a major threat to albatross populations worldwide.  However, fishery discards and offal produced in large quantities might benefit some scavenging seabirds.  Here, we demonstrate an integrated approach to better understand the ecological ramifications of fine-scale overlap between seabirds and fisheries.  As a case study, we examined whether foraging in association with a fishing vessel is advantageous for chick provisioning in terms of quantity of food delivered to chicks, in northern royal albatross (Diomedea sanfordi) at Taiaroa Head, New Zealand.  Fine-scale overlap between albatrosses and vessels was quantified by integrating GPS tracking and Vessel Monitoring Systems (VMS).  Meal size delivered to chicks was measured using custom-designed nest balances, and monitoring of attendance of adults fitted with radio transmitters was used in conjunction with time-lapse photography at the nest allowed us to allocate each feeding event to a specific parent.  The combination of these techniques enabled comparison of meal sizes delivered to chicks with parental foraging trip durations with or without fishing vessels association.  A total of 45 foraging trips and associated chick feeding events were monitored during the chick-rearing period in 2012.  Differences in the meal size and foraging trip duration relative to foraging overlap with fisheries were examined using a linear mixed-effect model, adjusted for chick age.  Our results, based on three birds, suggest that foraging in association with vessels does not confer an advantage for chick feeding for this population that demonstrated low rates of overlap while foraging.  The integrated research design presented can be applied to other seabird species that are susceptible to bycatch, and offers a valuable approach to evaluate habitat quality by linking habitat use and foraging success in terms of total amount of food delivered to offspring.”

A Northern Royal Albatross bears a GPS tracking system

A Northern Royal Albatross feeds its chick sitting on a nest balance

Photographs by Junichi Sugishita 

With thanks to Junichi Sugishita for information and photographs.

Reference:

Sugishita, J., Torres, L.G. & Seddon, P.J. 2015.  A new approach to study of seabird-fishery overlap: connecting chick feeding with parental foraging and overlap with fishing vessels.  Global Ecology and Conservation 4: 632-644.

John Cooper, ACAP Information Officer, 05 December 2015

Wisdom, a female Laysan Albatross Phoebastria immutabilis who is at least 64 years old (click here) laid her latest egg on 28 November on USA’s Midway Atoll National Wildlife Refuge.

Her mate since at least 2012 (“Mr Goo”, named after his colour-band combination of G000) is currently taking the first long incubation shift (of up to month) while Wisdom is out to sea foraging.

Wisdom and Mr Goo last month before laying their latest egg, photograph by Kiah Walker

Photographs and video by Daniel Clark and Kiah Walker, US Fish & Wildlife Service.

John Cooper, ACAP Information Officer, 04 December 2015

For every season since 2010 the female-female pair of Short-tailed Albatrosses Phoebastria albatrus has returned to the USA’s Kure Atoll in the North-Western Hawaiian Islands to lay eggs (click here).

Both birds were banded as chicks so their current ages for their latest breeding attempt are known.  One is 15 years of age (banded in 2000) and is still in intermediate plumage.  The other bird is now 22 years old having been banded in 1993 and is in adult plumage.  All previous breeding attempts have failed during the incubation stage – which both birds share - as the eggs they each lay are assumed to be infertile (click here).

The intermediate-plumaged Short-tailed Albatross on Kure.

Photograph from Winter Season 2015/2016 Volunteer Ryan Potter’s blog on the Kure Atoll Conservancy website

John Cooper, ACAP Information Officer, 03 December 2015