Carine Precheur (CEBC, Université de La Rochelle, Villiers en Bois, France) and colleagues have published in the open-access journal Ecosphere on the relationships between signals of climate change and demography of the Audubon's Shearwater Puffinus lherminieri

The paper’s abstract follows:

“An understanding of how environmental changes affect life history traits and population dynamics is essential for predicting the effects of climate change, managing ecosystems, and determining how species and habitats can best be preserved. This applies particularly to seabirds, which, as top marine predators, are often considered as indicators of marine ecosystem changes. Most studies have so far been conducted in polar or temperate regions. However, important changes in the functioning of tropical marine ecosystems have been reported, but the responses of top predators remain poorly known. This study focused on a tropical seabird, Audubon's shearwater Puffinus lherminieri, analyzing the relationships between climate change and the survival of adults, nesting success, and population dynamics. The population studied breeds in Martinique, in the south of the Caribbean region, which is strongly influenced by the Amazon and Orinoco rivers. A data set for the period 1995 to 2014 was used to estimate the survival by age classes and breeding success and to determine which climate variables most affected demographic parameters. The population dynamics were modeled to predict the future population growth rates in response to climate change. The annual adult survival rate increased over the last 20 years, currently standing at 94% for adult birds more than 6 years old. Adult survival increased with sea surface temperature (SST) during the nonbreeding season as well as with Amazon River discharge, although the latter with a lag of 1 year. The effect of SST was explained by the positive relationship between SST and chlorophyll a during years of high discharge from the Amazon and Orinoco. The population decreased between 1995 and 2007 at a rate of 3% per year and then increased between 2008 and 2014 at a rate of 7% per year. The increase in adult survival observed should continue as temperatures increase in the future, and the population models predicted a stable or increasing population over the next 50 years (λ = 1.018). These results contrast with the negative effect of increasing SST on seabird populations found in temperate and polar regions, emphasizing the need to study the impact of climate change on tropical seabirds.”

Audubon's Shearwater, photograph by Carine Precheur

Click here for a recent ACAP Latest News item on Audubon’s Shearwater.

With thanks to Carine Precheur.

Reference:

Precheur, C., Barbraud, C., Martail, F., Mian, M., Nicolas, J.-C., Brithmer, R., Belfan, D., Conde, B. & Bretagnolle, V. 2016.  Some like it hot: effect of environment on population dynamics of a small tropical seabird in the Caribbean region.  Ecosphere 7.  DOI: 10.1002/ecs2.1461.

John Cooper, ACAP Information Officer, 05 June 2017

Last month ACAP attended the the 8th Meeting of the Inter-American Tropical Tuna Commission's (IATTC) Scientific Advisory Committee (SAC8, 8-12 May 2017), preceded by the 7th Meeting of the IATTC Working Group on Bycatch (BWG7, 5-6 May 2017) in La Jolla, California, USA.  The Agreement was represented by its Executive Secretary, Dr Marco Favero.

Yellowfin Tuna Thunnus albacares

ACAP contributed the following four papers which it introduced to the Bycatch Working Group:

• SAC-08 INF D(a)  Summary of tools and guidelines available to assist observers in the identification of seabird species and the handling of bycaught individuals (in collaboration with BirdLife International)
• SAC-08 INF D(b)  The development of ACAP seabird bycatch indicators, data needs, methodological approaches and reporting requirements
• SAC-08 INF D(c)  The conservation status and priorities for albatrosses and large petrels
• SAC-08 INF D(d)  Current ACAP advice for reducing the impact of pelagic longline fishing operations on seabirds

The information contained in the papers led to a number of seabird recommendations drafted by the BWG that were then presented to the SAC. All these recommendations on seabird issues were adopted by Scientific Advisory Committee, including:

1. That the existing guidelines and other tools relating to the removal of fishing hooks from incidentally caught seabirds be made available to CPCs (Contracting Parties and Cooperating Non-Contracting Parties) through the IATTC web site;
2. A request for the improvement in seabird data in annual reports by CPCs pursuant to Paragraph 7 of Resolution C-11-02 to Mitigate the Impact on Seabirds of Fishing for Species covered by the IATTC; for example the identification to seabird species, and the provision of spatial and temporal stratified bycatch data, amongst others;
3. That the Commission analyze the extent of implementation by CPCs of the measures contained in Resolution C-11-02 with a view to updating the measure, if necessary; and
4. That the Commission consider revising the suite of mitigation measures in Resolution C-11-02.

Also relevant to the ACAP agenda were recommendations on electronic monitoring encouraging the development of pilot projects in longline vessels, and the inclusion in national reports of any relevant information on the use of electronic monitoring systems at the national level.

Further collaboration between ACAP and IATTC will include engagement with fishing nations to improve data collection, reporting and analysis, and the possible update of the current seabird conservation measure. The collaboration will include ACAP’s attendance at the upcoming 92nd Meeting of the IATTC, to be held in Mexico City, México  from 24 to 28 July 2017, which will offer the opportunity to the Secretariats to sign the renewal of the Memorandum of Understanding between both organisations.

Marco Favero, ACAP Executive Secretary, 02 June 2017

Dominic Rollinson (Percy FitzPatrick Institute, University of Cape Town, Rondebosch, South Africa) has reported  in the on-line and open-access (but not peer-reviewed) publication Biodiversity Observations on five Critically Endangered Tristan Albatrosses Diomedea dabbenena colour banded on Gough Island that were subsequently observed in southern African waters.

“All of the individuals observed were adult males, aged 19 - 35 years.  Four of the five birds had attempted to breed in the last 1-2 years, however all had failed”.

A colour-banded Tristan Albatross at sea, photograph by Meidad Goran

Read more on the at-sea distribution of colour-banded Tristan Albatrosses in ACAP Latest News here.

Reference:

Rollinson, D.P. 2016. At-sea sightings of banded Tristan Albatrosses off the Western Cape and a review of records in southern African waters. Biodiversity Observations 7.66: 1- 4.

John Cooper, ACAP Information Officer, 01 June 2017

Livingston Island belongs to the South Shetland Island group in Maritime Antarctica. It lies between Snow Island and Greenwich Island, approximately 110 km from the Antarctic Continent, separated by the Bransfield Strait.  The Southern Giant Petrel Macronectes giganteus is the only ACAP-listed species breeding on Livingston Island, at two known localities, Hannah Point and Byers Peninsula (ACAP Site No. 85).

Hannah Point is a narrow peninsula on the south coast of Livingston Island of c. 122 ha with elevations 30 to 50 m above sea level.  The area becomes ice-free during the austral summer mainly due to steep slopes and hills that do not accumulate ice and snow.

The Southern Giant Petrel population at Hannah Point is of c. 308 breeding pairs divided into six breeding groups and some solitary nests, according to the last ground census in December 2012 by Brazilian researchers from the Universidade do Vale do Rio dos Sinos.  This represents a marked increase from counts of only 17 pairs in 1958, 24 pairs in 1986, and 110-246 occupied nests from 1997/98 to 2005 by the Antarctic Site Inventory.  Nests are located on elevated areas with gentle slopes covered by sediment, boulders and pebbles, which are used in nest construction.

A Southern Giant Petrel colony  at Hannah Point

A White-phase Southern Giant Petrel on its pebble nest at Hannah Point

Due to the high frequency of tourists visiting Hannah Point each year the area is managed by a Visitor Site Guide document produced by the Antarctic Treaty System.

Views of Hannah Point

Moss and pebbles make a Southern Giant Petrel nest at Hannah Point

Photographs by Maria Virginia Petry.

Selected Literature:

Antarctic Treaty System 2014.  Hannah Point Antarctic Treaty Visitor Site Guide. 2 pp.

Harris, C.M., Lorenz, K., Fishpool, L.D.C., Lascelles, B., Cooper, J., Coria, N.R., Croxall, J.P., Emmerson, L.M., Fijn, R., Fraser, W.L., Jouventin, P., LaRue, M.A., Le Maho, Y., Lynch, H.J., Naveen, R., Patterson-Fraser, D.L., Peter, H.-U., Poncet, S., Phillips, R.A., Southwell, C.J., van Franeker, J.A., Weimerskirch, H., Wienecke, B. & Woehler, E.J. 2015.  Important Bird Areas in Antarctica 2015.  Cambridge: BirdLife International and Environmental Research & Assessment Ltd.  302 pp.

Lynch, J.J., Naveen, R. & Fagan, W.F. 2008.  Censuses of penguin, Blue-eyed Shag Phalacrocorax atriceps and Southern Giant Petrel Macronectes giganteus populations on the Antarctic Peninsula, 2001-2007.  Marine Ornithology 36: 83-97.

Naveen, R. 1997.  The Oceanites Site Guide to the Antarctic Peninsula.  Chevy Chase: Oceanites Inc.  129 pp.

Naveen, R. 2003. Compendium of Antarctic Peninsula Visitor Sites 2nd Edition.  A Report to the United States Environmental Protection Agency. Chevy Chase: Oceanites Inc.  381 pp.

Naveen, R., Forrest, S.C., Dagit, R.G., Blight, L.K., Trivelpiece, W.Z. & Trivelpiece, S.G. 2000.  Censuses of penguin, Blue-eyed Shag, and Southern Giant Petrel populations in the Antarctic Peninsula region , 1994-2000.  Polar Record 36: 323-334.

Patterson, D.L., Woehler, E.J., Croxall, J.P., Cooper, J., Poncet, S., Peter, H.-U., Hunter, S. & Fraser, W.R. 2008.  Breeding distribution and population status of the Northern Giant Petrel Macronectes halli and the Southern Giant Petrel M. giganteus.  Marine Ornithology 36: 115-124 & appendices.

Poncet, S. & Poncet, J. 2007.  Southern Ocean Cruising Second Edition.  Cambridge: Environmental Research & Assessment.  160 pp.

Maria Virginia Petry & Júlia Victória Grohmann Finger, Laboratório de Ornitologia e Animais Marinhos, Universidade do Vale do Rio dos Sinos, São Leopoldo, Brazil, 31 May 2017