Henri Weimerskirch (Centre d’Etudes Biologiques de Chizé, Villiers en Bois, France) and colleagues have published in the online and open-access journal Scientific Reports on differing migratory strategies of two populations of Wandering Albatrosses Diomedea exulans.

The paper’s abstract follows:

“Migratory behavior, routes and zones used during the non-breeding season are assumed to have been selected to maximize fitness, and can lead to genetic differentiation.  Yet, here we show that migration strategies differ markedly between and within two genetically similar populations of wandering albatross Diomedea exulans from the Crozet and Kerguelen archipelagos in the Indian Ocean.  Wandering albatrosses usually breed biennially if successful, and during the sabbatical year, all birds from Kerguelen migrate to the Pacific Ocean, whereas most from Crozet are sedentary.  Instead of taking the shortest routes, which would involve a return against headwinds, migratory birds fly with the westerly winds, requiring detours of 10,000s km.  In total, migrants circumnavigate Antarctica 2 to 3 times, covering more than 120,000 km in a single sabbatical year.  Our results indicate strong links between migratory behavior and fitness; all birds from Kerguelen breed biennially, whereas a significant proportion of those from Crozet, especially females, are sedentary and breed in consecutive calendar years.  To breed annually, these females temporarily change mate, but return to their original partner in the following year.  This extreme variation in migratory behavior has important consequences in term of life history evolution and susceptibility to climate change and fisheries."

Wandering Albatross at sea, photograph by John Chardine

With thanks to Richard Phillips for information.

Reference:

Henri Weimerskirch, H., Delord, K., Guitteaud, A., Phillips, R.A. & Pinet, P.  2015.  Extreme variation in migration strategies between and within wandering albatross populations during their sabbatical year, and their fitness consequences.  Scientific Reports 5, No. 8853.  doi:10.1038/srep08853.

J. Cooper, ACAP Information Officer, 14 March 2015

Maite Louzao (Centro Oceanográfico de Gijón/Xixón, Spain) and colleagues have published early-view in the journal Marine Ornithology on krill regurgitated by a ACAP-listed and Critically Endangered Balearic Shearwater Puffinus mauretanicus during the chick-rearing season.

“In this study, we report observations that, during breeding season, the diet of the endemic Balearic Shearwater includes macrozooplankton, specifically the krill Nyctiphanes couchii.  Further research in needed to accurately assess the importance of euphausiids in the diet of the Balearic Shearwater.”

Balearic Shearwater, photograph by Daniel Oro 

Reference:

Louzao, M., García, D., Rodríguez, B. & Abelló, P. 2015.  Evidence of krill in the diet of Balearic Shearwaters Puffinus mauretanicus.  Marine Ornithology 43: 49-51.

John Cooper, ACAP Information Officer, 13 March 2015

Leigh Torres (Marine Mammal Institute, Department of Fisheries and Wildlife, Oregon State University, Newport, Oregon, USA) and colleagues have published in the open-access, online journal PloS ONE on modelling at-sea distribution of ACAP-listed Grey Petrels Procellaria cinerea from three different populations.

The paper’s abstract follows:

“Species distribution models (SDMs) are increasingly applied in conservation management to predict suitable habitat for poorly known populations.  High predictive performance of SDMs is evident in validations performed within the model calibration area (interpolation), but few studies have assessed SDM transferability to novel areas (extrapolation), particularly across large spatial scales or pelagic ecosystems.  We performed rigorous SDM validation tests on distribution data from three populations of a long-ranging marine predator, the grey petrel Procellaria cinerea, to assess model transferability across the Southern Hemisphere (25-65°S).  Oceanographic data were combined with tracks of grey petrels from two remote sub-Antarctic islands (Antipodes and Kerguelen) using boosted regression trees to generate three SDMs: one for each island population, and a combined model.  The predictive performance of these models was assessed using withheld tracking data from within the model calibration areas (interpolation), and from a third population, Marion Island (extrapolation).  Predictive performance was assessed using k-fold cross validation and point biserial correlation.  The two population-specific SDMs included the same predictor variables and suggested birds responded to the same broad-scale oceanographic influences.  However, all model validation tests, including of the combined model, determined strong interpolation but weak extrapolation capabilities.  These results indicate that habitat use reflects both its availability and bird preferences, such that the realized distribution patterns differ for each population.  The spatial predictions by the three SDMs were compared with tracking data and fishing effort to demonstrate the conservation pitfalls of extrapolating SDMs outside calibration regions.  This exercise revealed that SDM predictions would have led to an underestimate of overlap with fishing effort and potentially misinformed bycatch mitigation efforts.  Although SDMs can elucidate potential distribution patterns relative to large-scale climatic and oceanographic conditions, knowledge of local habitat availability and preferences is necessary to understand and successfully predict region-specific realized distribution patterns.”

Grey Petrel at sea, photograph by Peter Ryan

Reference:

Torres, L.G., Sutton, P.J.H., Thompson, D.R., Delord, K., Weimerskirch, H., Sagar, P.M., Sommer, E., Dilley, B.J., Ryan, P.G. & Phillips, R.A. 2015.  Poor transferability of species distribution models for a pelagic predator, the Grey Petrel, indicates contrasting habitat preferences across ocean basins.  PloS ONE  DOI: 10.1371/journal.pone.0120014.

John Cooper, ACAP Information Officer, 12 March 2015

The first World Seabird Twitter Conference (#WSTC1) gets underway on 20 and 21 March.

“A Twitter conference is a social media event that occurs from the comfort of your living room!! (or wherever you might be currently seated).  This event is meant to bring together seabird scientists from around the world in an online setting to encourage communication and collaboration, particularly when costs of travel are currently high.”

Registration is now closed with 42 “talks” offered from 12 countries.  Presentations will consist of a maximum of six 140-character tweets with 15-minute time slots accorded to each author over the two-day time period.  Discussion and questions are encouraged by sending tweets to the authors.

Of the 42 talks to be tweeted at least eight will be about procellariiform seabirds as listed here by author and title.

Martin Berg:  Using the fluttering shearwater (Puffinus gavia) as an ecological indicator for marine ecosystem health in northern New Zealand.

Rachel Buxton:  One method does not suit all: variable settlement responses of three procellariid species to vocalization playbacks.

Rachael Sagar:  Optimising translocation efforts of Mottled Petrels (Pterodroma inexpectata): growth, provisioning, meal size and the efficacy of an artificial diet for chicks

Dilek Sahlin:  Are there more yelkouan shearwaters than we thought? [Puffinus yelkouan].

Matthew Savoca:  Procellariiform seabirds link chemical ecology to marine biogeochemistry: implications and future directions.

Kylie Scales: Ensemble ecological niche models identify preferred foraging habitats of grey-headed albatrosses Thalassarche chrysostoma.

Alice Treval:  Elevated levels of plastic ingestion by a high-Arctic seabird: the northern fulmar (Fulmarus glacialis).

Saskia Wischnewski:  Exceptionally long provisioning trips to the mid-Atlantic and western Scotland by Manx Shearwaters (Puffinus puffinus) breeding on the edge of Europe.

A Fluttering Shearwater in its artificial burrow, photograph my Shane Cotter

Click here to for details of time slots and authors’ twitter handles.

Following a judging process the winner of the first WSTC will be awarded a free registration to the Second World Seabird Conference to be held in Cape Town, South Africa in October this year.

Click here to read more about this innovative use of social media.

John Cooper, ACAP Information Officer, 11 March 2015