The reintroduction programs

The project

The idea of a reintroduction program was born in the head of Jacques-Olivier TRAVERS in 2007. At that time the white-tailed sea eagle had disappeared from France since 1959 (Corsica) and 1892 (Thonon les Bains) and the hopes of a quick return seemed very slim.

Since my childhood, I have a passion for this eagle that I discovered in a book of the Swiss ornithologist Paul Géroudet, I immediately dreamed to see it again in the sky of our country. The road was long because there were very few in captivity and the naturalist community was not very keen to undertake a reintroduction program ».

Gros plan sur un œuf sur fond noir éclairé en rouge, on distingue le bébé à l'intérieur.

Success in reproducing the species

In 2007, there were almost no white-tailed eagles in captivity in France and reproduction of the species in zoos was rare. The Park of the eagles of Léman brought the first individuals from Russia in 2009. From 2012 the first couple is formed; it will take four years to reproduce. From 2017 new couples are formed and gradually 2 then 3 couples that reproduce each year. Thanks to the cooperation of French (Puy du Fou, Amnéville) and European (Veldhoven zoo) zoos, 9 pairs, including 5 breeders, will be housed at Les Aigles du Léman in 2021.

To make the species known

To reintroduce a species, it is important that it is perfectly accepted by the public who will be in contact with it. We have chosen to do a national communication campaign to make the public discover this species. As we don’t have big means at our disposal, we have chosen to make an original campaign based on the production of films and innovative events. During the years 2014 to 2019 we have participated, written, directed, or produced more than a dozen documentaries on white-tailed sea eagles. At the same time our birds have been seen from the Eiffel Tower, the Burj Khalifa, the Olympic Stadium in London, in Vienna, Berlin Rotterdam…The images from the cameras on the backs of our eagles have revealed a unique view of the great glaciers of the Alps, the deserts of the Middle East or the Greek islands…

Photo de Jacques-olivier Travers avec son pygargue à queue blanche ayant les ailes déployées devant la tour Eiffel à Paris.
Pygargue à queue blanche en vol en piqué sur le Tower Bridge en Angleterre.

Creating a consensus

We wanted to make this reintroduction a true regional project and create strong local support. To do this, we consulted all the stakeholders for nearly 2 years: Naturalist association, fisherman, elected officials, scientists, teachers. Through studies, consultations and improvements, the project has gained general approval, which has been reinforced by the discovery of the last reproduction in continental France at Thonon les Bains. This gives all its sense to this project strongly anchored in the preservation of the local heritage.

The parental cleat, our method

For a long time, falconers and naturalists have understood that young birds are able to learn to fly and hunt alone in their first weeks of life. The young birds are taken from nests in the wild or in zoos, brought to the reintroduction area, raised together and then released with food supplementation for a few months. This technique has been proven successful in all reintroduction programs around the world, it’s called hacking.

However, the abrupt separation from the parents and the short time spent on the reintroduction site seem to limit the survival rate of the young. Our idea is to try to improve the survival rate and the fixation on the territory of the young with a new technique that we have named: the parental cleat.

The young are raised directly on the reintroduction site by their parents, in a large aviary, until the age of 8 weeks then they are placed in an external nest but in contact with the parents simply separated by bars. They will thus be able to emancipate themselves at their own pace without any break with the parents. This will not create any trauma linked to the separation with the parents and to the transport to an unknown release site. The studies carried out around this new technique will allow us to know if Jacques-Olivier’s intuition was right or not and if in the future it presents a real evolution for the reintroduction programs.

Scientific research

The eagle reintroduction project in the Lake Geneva basin will allow many scientists to analyze the data provided by the video surveillance of the birds, the GPS tracking, and the field observations. Publications will regularly report on the progress made by the scientists with whom we collaborate. The work will focus on the following main points :

Validation of the parental cleat technique : The originality of this reintroduction project lies in this new release technique. The objective of the studies that will take place throughout the program (8 years) will try to verify if this new technique brings benefits on the young survival rate and the fixation of the birds on the territory, two crucial points of the reintroduction program. The phenomenon of recognition of parents will also be studied for a non-colonial species since the eaglets will be able to join their parents as well as other parents because all nests are close. There fore, eaglets can choose the nest where they come back to beg food to adult.

Bird movement :Placing a GPS tag on each reintroduced eagle will allow us to follow bird movement.

Where do they go? How long do they stay in the reintroduction area? Will they join other populations?

These essential questions to understand the possible reconquest of the national territory will be analyzed by one of the best specialists of the question: Bernd Meybug.

The life cycle : The life cycles of birds will also be studied. Modern beacons allow us to know if the birds areactive or not, at what height they fly, how long they spend per day, if they fish or eat carrion…

We will also be able to study the causes of mortality of these eaglets and try to remedy.

Nature’s marvel. ©RemiChapeaublanc