At the Irstea Nogent-sur-Vernisson site, scientists are studying the interactions between wild ungulates (particularly deer and boar), the forest, and forest management practices. Through the work carried out at the Chambord national estate, they have been able to simultaneously study various aspects of these relationships and gain more insight into the services the animals provide, particularly in relation to forest ecosystem operation.
By consuming understory vegetation, dispersing seeds or turning the soil, deer, roe deer and wild boar play an important role in the forest ecosystem. In order to better define the processes involved, scientists from the Forest Ecosystems unit at Irstea Nogent-sur-Vernisson are currently running a research project in the prestigious Chambord national estate, a classified UNESCO world heritage site. The project is part of the Intelligence des patrimoines (Heritage Intelligence) program in the Centre-Val de Loire region, which aims to create socioeconomic value for research results. Known as Costaud1, the project aims to provide more insight into the contribution of ungulates to the operation of the ecosystem and the services provided to the Chambord estate, the largest enclosed forest park in Europe. Using an interdisciplinary, geohistorical, ecological and sociocultural approach, scientists have focused on how the landscape of the site, initially created as a hunting lodge for French king François I, has been molded over time by humans, particularly by hunting practices, and in parallel, how the ungulate population, kept high on the site, has impacted the ecological processes and biodiversity of the ecosystem.
"From a research perspective, the Chambord estate represents an exceptional experimental site: not only does it concentrate a high population of deer and wild boar in an enclosed estate, but given the historical hunting and extraction practices used to repopulate other forested areas, it also had the logistical capacity to capture and tag these large animals, making handling the individuals that our studies require a much easier task," clarifies Christophe Baltzinger, Irstea researcher in forest ecology and project manager.
Ungulates, the "Noah's ark" of forest plants
One of the project's results is a map tracing the history of the landscape from 1785 to today, which has been used to highlight its evolution: half forest and half agricultural in the 18th century, the estate was almost entirely covered in forest from the 19th century, as it is today. This change means it is now more suitable for ungulates, particularly with the creation of grassland areas over the last 50 years that are especially suited to their diet.
Aside from this geohistorical study, scientists obtained interesting results for ecological processes. For example, using several experiments aimed at studying seed dispersal mechanisms, usually transported by animal fur, scientists were able to show that regardless of species, most seeds fall very quickly (within the first hour), while a small proportion remain attached for a long time (less than 10% after 6 hours and 1% for more than two days) and are therefore transported across long distances, sometimes up to 3 kilometers away. They also discovered a new element that contributes to increasing this dispersal: a process of seed transfer between animals that occurs during social play or grooming activities.
"These results are particularly interesting to understand ungulate management in relation to forestry activity. The results show that although the diet of these large herbivores can limit or delay the growth of certain tree species that are relevant to forest managers, they also provide key services to the natural environment. As they travel over long distances, they help plants find better habitats and adapt to environmental changes, such as variations in land use or climate change," concludes Baltzinger.
In addition to improving scientific knowledge of these animal species, the conclusions of the Costaud project will provide information about the Chambord estate to be distributed to the general public: explanatory signs will be put up along the Grand Promenade, a trail through the Chambord forest that was opened to visitors in the summer of 2017.
Save the date: International conference on forest habitats and inhabited forests
On March 26 and 27, 2019, Irstea and other partners in the Costaud project are organizing an international conference focusing on interactions between usage, management methods, social practices and wild forest animals. Organized for managers (natural environments, animal populations) and scientists involved in the subject, the conference will be held at the Château de Chambord.
For more information
- Consult the web pages of the Forest Ecosystems research unit at the Irstea Nogent-sur-Vernisson Center
1- Contribution of wild ungulates to ecosystem operations and services provided in Chambord, Chambord-Châteaux restoration for the Heritage Intelligence program (2015-2018). Partners: Irstea; Laboratoire Cités, Territoires, Environnement et Sociétés [Cities, Regions, Environment and Companies Laboratory]; INSA Centre Val de Loire; Centre d’études supérieures sur la Renaissance [Renaissance Higher Education Center]; Domaine national de Chambord [Chambord National Estate]; Réserve de La Haute Touche [Haute Touche Zoological Park]; Office National de la Chasse et de la Faune Sauvage [National Office for Wildlife and Hunting].