A study on the Coryʼs shearwater will help protecting new marine areas in international waters

Seabirds are the most endangered bird species in the world due to fishing practices, predation and the loss of breeding habitat.
Seabirds are the most endangered bird species in the world due to fishing practices, predation and the loss of breeding habitat.
Research
(31/01/2018)

The adult specimens of Coryʼs shearwater (Calonectris diomedea) in the Canary Islands travel more than 800 kilometres for days searching for food. In Mediterranean colonies, these marine birds do not fly further than 300 kilometres from their colonies. A study on these movements provides now, for the first time, a detailed information on the movements of the Spanish populations of the shearwaters from the Atlantic and the Mediterranean Sea over the year. This is the monograph Migración y ecología espacial de las poblaciones españolas de pardela cenicienta, which shows a million locations of these sea birds.

Seabirds are the most endangered bird species in the world due to fishing practices, predation and the loss of breeding habitat.
Seabirds are the most endangered bird species in the world due to fishing practices, predation and the loss of breeding habitat.
Research
31/01/2018

The adult specimens of Coryʼs shearwater (Calonectris diomedea) in the Canary Islands travel more than 800 kilometres for days searching for food. In Mediterranean colonies, these marine birds do not fly further than 300 kilometres from their colonies. A study on these movements provides now, for the first time, a detailed information on the movements of the Spanish populations of the shearwaters from the Atlantic and the Mediterranean Sea over the year. This is the monograph Migración y ecología espacial de las poblaciones españolas de pardela cenicienta, which shows a million locations of these sea birds.

 

This new publication gathers research studies driven by experts on the study of marine birds, their spatial ecology and preservation, from the Faculty of Biology and the Biodiversity Research Institute of the University of Barcelona (IRBio), IMEDEA and SEO/BirdLife. These scientific teams have conducted a series of researches over a decade, to know about the basic aspects of the ecology of the shearwater and improve its preservation. By collecting this work, this publication is now presenting, for the first time, many of these aspects, which were still unpublished. 

More than a million locations with remote tracking systems

Coryʼs shearwater (Calonectris diomedea) is one of the most representative birds in our seas. With populations that are suffering a severe decline, it was chosen as Bird of the Year in 2013 by the NGO SEO/BirdLife as an emblematic species that reflects the problem of preservation of marine birds in our seas.

Within the frame of the study, from 2007 to 2015, experts marked 460 shearwaters with GPS and other electronic devices in 13 breeding colonies around different regions of Spain: the Balearic Islands, Castellón, Murcia, Almería, Galicia, Canary Islands and Chafarinas Islands. Overall, a total of more than a million locations provides detailed results about the movements of these birds throughout the year, as well as their at-sea ecology (commuting, feeding and resting areas during their breeding season, behavior in their wintering areas, characterization of their migration corridors that connect breeding with wintering areas). "This is one of the most ambitious studies conducted so far on the movement ecology of bird species in the State using state-of-the-art tracking technologies" says the researcher José Manuel de los Reyes (UB-IRBio), first author of the study.

The shearwaterʼs long journey through the ocean

During their breeding season, adults leave the nest for days and travel hundreds of kilometres while foraging. Their migration journeys to wintering areas are even more impressive, since they go around the South Atlantic and some even reach the Indian Ocean.

“In particular, the Mediterranean populations migrate to four different wintering areas, which are the Canary Current, Angola and Namibian waters, the central Atlantic waters and the Gulf of Guinea. Birds from Atlantic colonies, however, use five wintering areas: the Benguela Current, the Agulhas Current, the Brasil Current and the central South Atlantic. Most of these birds are loyal to the same wintering area over the years”, says Jacob González-Solís, lecturer from the Department of Evolutionary Biology, Ecology and Environmental Sciences and IRBio, head of the working group on marine birds that led this study.

Being up on the species in order to improve their conservation status

There is a great amount of data on Coryʼs shearwater birds to track their flyways ─most of its information was used in this monograph. However, “so far there are only a few areas that were specifically proposed for their conservation beyond the State scope, despite of the importance of the international waters for these species, as stated in this study”, says José Manuel Arcos, head of the SEO/BirdLife marine program. “Protecting places that are relevant for the species in international waters or in other countries will require multilateral international agreements, a process BirdLife International has already started working on, with the identification and proposals by marine IBA”, adds Arcos.

Knowing about the distribution of Coryʼs shearwater allows researchers to identify the places where their activity is overlapped with threats coming from human activity (such as the accidental catch in longlines and other fishing gears, the main threat that causes hundreds of bird deaths in the Mediterranean Sea every year. Analysing the overlap of these fishing activities with longlines will ease the design of mitigation measures for each area. One of the future challenges lies within the fact that social and political stakeholders involved aim to set effective conservation measures ─such as measures to reduce shearwater bycatch in fisheries and actions to incorporate new generation tools, in order to improve management actions and thus conservation status and of these species and their ecosystems.

At a State level, the data provided in this report supports the areas that were previously identified in the inventory of the Important Bird and Biodiversity Areas (IBA), currently added to the Natura 2000 network as a Special Protection Area for Birds (ZEPA).

The new monograph is the third one in Migra program, an initiative driven by SEO/BirdLife in collaboration with Iberdrola España Foundation. Launched in 2011, Migra brings the latest technology on geolocalisation and remote tracking to know about the movements of birds within and outside the country in detail.