Population dynamics, ecology and conservation of the white stork in western France
Following a few episodic reproductions between 1960 and 1966, the white stork has been breeding continuously in Charente-Maritime and the marshes of western France since 1978. Charente-Maritime currently hosts the largest population of nesting white storks in France, with more than 520 pairs in 2019.
A research and conservation programme has been initiated and developed since 1978 by the Groupe Ornithologique Aunis Saintonge (GOAS) under the aegis of the Centre de Recherche sur la Biologie des Populations d’Oiseaux (National Museum of Natural History), with which the Centre d’Etudes Biologiques de Chizé (CNRS) has been associated since 2001, in collaboration with the research institute BioSphère Environnement and ACROLA (Association pour la Connaissance et la Recherche Ornithologique Loire Atlantique) since 2016.
The main objectives are:
- to understand the demographics and dynamics of this population and to identify the climatic and environmental factors that may affect it.
- to determine the home ranges of adults during the breeding season.
- refine knowledge on migration and wintering strategies.
The results from this program provide a better understanding of people’s response to climate change and assist in wetland conservation strategies.
This program is based on the long-term monitoring of banded individuals and, since 2019, on the installation of GPS beacons on a limited sample of individuals.
The population of white storks in Charente-Maritime is a wild population.
The sharp increase in the number of pairs since 1988 is mainly due to the immigration of storks born in Spain, Switzerland, Holland, Poland and other French departments, as well as the recruitment of many chicks born in Charente-Maritime.
For several years the number of breeding pairs has also been increasing in other regions of France (Gironde, Loire-Atlantique, Vendée, Landes, Alsace).
Banding has made it possible to identify wintering grounds: Sahelian Africa and Spain. In the Sahel, the survival of individuals depends on the amount of rainfall, while in Spain open dumps favour storks that find food there.
The maintenance of this population depends on the conservation of the Charente marshes.
In Charente Maritime, storks feed mainly on aquatic insects, courtilières and, since recently, introduced American crayfish. They also eat frogs and small mammals.
The Charente population is not currently threatened. The results of the program allow us to affirm that this population could strongly decrease or disappear if:
-marshland areas around nesting sites were disappearing as a result of cultivation.
– major droughts were taking place in the wintering areas (Sahel)
The closure of landfills, particularly in Spain, in the coming years could have an influence on the survival of individuals and thus on the size of the population.
If you have observed a banded stork or found a dead banded stork, we are interested in this information. By sending us this information you are contributing to the research program on this species.
Some publications from the programme
Gadenne, H., Cornulier, T., Eraud, C., Barbraud, J.-C. & Barbraud, C. 2014. Evidence for density-dependent habitat selection at varying scales in an expanding bird population. Population Ecology 56: 493-506
Nevoux, M., Barbraud, J.-C. & Barbraud, C. 2008. Non-linear relationships between climate and vital rates in a migratory white stork population. Journal of Animal Ecology 77: 1143-1152.
Saether, B.-E., Grøtan, V., Tryjanowski, P, Barbraud, C., Engen, S & Fulin, M. 2006. Climate and spatio-temporal variation in the population dynamics of a long-distance migrant, the white stork. Journal of Animal Ecology 75: 80-90.
Barbraud, C., Delord, K., Barbraud, J.-C. & Barbraud, M. 2002. Changements récents dans le régime alimentaire des poussins de Cigogne blanche Ciconia ciconia en Charente-Maritime (centre-ouest, France). Alauda 70: 437-444.
Barbraud, C., Barbraud, J.-C. & Barbraud, M. 1999. Population dynamics of the White Stork Ciconia ciconia in western France. Ibis 141: 469-479.
Barbraud, C. & Barbraud, J.-C. 1998. Le régime alimentaire des poussins de Cigogne blanche Ciconia ciconia, en Charente-Maritime: importance des insectes. Alauda 65: 259-262.
Barbraud, J.-C. 1978. Nidification de la Cigogne blanche (Ciconia ciconia) en 1978 en Charente-Maritime. Trajhasse 8: 11-13.