Fragile interfaces between land and sea, rocky foreshores are under increasing pressure due to global changes. Monitoring their ecological status is one of the many challenges of the decade to achieve a sustainable environment. Cam Ly RINTZ, a doctoral student at the National Museum of Natural History, is devoting her thesis to the development of bioindicators to monitor the ecological status of these rocky foreshores through participatory science. In a transdisciplinary approach combining ecology and sociology, her ESPOIRS (HOPE) project actively involves citizens.
By Carole Saout-Grit and Laurie Henry
Cover photo: Fucus and Littorina © Cam Ly RINTZ
Rocky foreshores, treasures of biodiversity
Rocky foreshores are key ecosystems for coastal biodiversity, with stratified habitats where algae, invertebrates and microorganisms interact. While they play a fundamental role in primary productivity, biogeochemical regulation and coastal food webs, they are also particularly sensitive to anthropogenic disturbances. Pollution, global warming and the spread of invasive species are all pressures that alter their equilibrium.
However, monitoring their state of health remains limited due to a lack of continuous data and suitable bioindicators. To compensate for this lack, some scientific programmes are using participatory science, which often offers a high increased sampling capacity (particularly for the observation of coastal ecosystems) while involving citizens in the scientific process.
Nevertheless, participatory science requires a rigorous evaluation of the quality of the data collected as well as an adaptation of the protocols to guarantee a rigorous use of the measurements. To address this challenge, Cam Ly Rintz, a doctoral student at the Muséum National d’Histoire Naturelle (MNHN), is conducting thesis research on strengthening protocols in order to develop bioindicators capable of reflecting the state of rocky foreshores in response to global changes.
Alongside the ecological aspect, a sociological aspect will enable an in-depth study of the co-construction approach between scientists and civil society, to better understand the process of including participants and taking into account their knowledge and perceptions.
An innovative thesis in the extension of dedicated observatories
In France, since 2011, the participatory science programme entitled BioLit, run by the Planète Mer association and supported by the MNHN, has contributed to the observation of rocky foreshores. More specifically, its Algues Brunes et Bigorneaux (ABB) observatory, dedicated to the observation of brown algae, has already made it possible to collect data on the biodiversity of these environments.
However, several limitations hinder the exploitation of this data: the absence of robust time series, the difficulty of a differentiated analysis of the impacts of pollutants and the need to integrate a more refined approach to climate change.
In view of these findings, the ESPOIRS thesis conducted by Cam Ly aims to develop reliable bioindicators in co-construction with citizens. These tools will make it possible to assess the ecological state of rocky foreshores and their response to environmental pressures, while strengthening the involvement of the general public in the scientific process. Driven by a passion born of his childhood on a Pacific island, Cam Ly aims to build bridges between science and society to better preserve these essential and vulnerable environments.
Cam Ly Rintz © C. Mebarki
Bioindicators to anticipate the future of foreshores
The main objective of the ESPOIRS (HOPE) project is to structure a methodological framework for assessing the health of rocky foreshores in the face of pollution and climate change for certain metropolitan marine and coastal areas identified as vulnerable. The thesis is therefore divided into three parts:
- Pollution analysis
By assessing the sensitivity of brown algae and gastropods to nutrients (nitrogen, phosphorus), this component aims to identify relevant biological indicators to monitor the eutrophication of foreshores. An adaptation of the Brown Algae and Periwinkles protocol is being developed to better characterise foreshore communities in the face of this pressure.
- Impacts of climate change
The distribution of marine species is being disrupted by climate variations. Using a digital modelling approach, this research aims to understand how foreshore communities are evolving under the effect of global warming and to predict future transformations.
- Integration of participatory sciences and sociology
Finally, this project makes it a point of honour to involve citizens, scientists and decision-makers in the design of bioindicators. Through co-construction workshops, the aim is to involve local actors in coastal surveillance and to enhance their contribution to scientific knowledge.
Test of the protocol with the participants of ESPOIRS © C. Mebarki
The thesis is supervised by Éric Feunteun (MNHN), Florian Charvolin (CNRS) and Boris Leroy (MNHN) and is being carried out at the MNHN marine station in Dinard. Funded for three years as part of the Priority Research Programme (PRP) Ocean & Climate, the project addresses the challenges related to the resilience of coastal socio-ecosystems and the improvement of tools for monitoring global changes.
Ultimately, the ESPOIRS project aims to provide proof of concept demonstrating that participatory sciences can be a powerful lever for producing robust and accessible indicators; a key issue for anticipating changes in coastlines and promoting adaptive management of these fragile environments. With ESPOIRS, science is opening up to citizens and regions, illustrating how research can become a driving force for collective mobilisation in the face of the environmental challenges of the 21st century.
3 Questions to Cam Ly Rintz
Why did you want to do a thesis in marine sciences?
I grew up on an island in the Pacific where we live alongside the ocean on a daily basis, and where it plays an important role in the culture. I learned to love it and to be amazed by it, and this passion only grew stronger as I studied. In addition, my sensitivity to ecological issues led me to focus on conservation science. Through research, I hope to make my contribution to the protection of these fascinating and vulnerable environments, which are indispensable and yet threatened, to preserve this abundant life and so that future generations can continue to be amazed.
What made you want to apply for this thesis topic? What motivated you?
The first keywords that attracted me were participatory sciences. I was particularly keen to work on this subject, for the scientific contributions and challenges it represents, to think about another way of doing science by questioning and changing the science-society and nature-society relationships. Then, I really liked the transdisciplinary approach with an opening to sociology, a discipline which, in my opinion, is inextricably linked to ecology. Finally, I embarked on this thesis because I knew that I was joining a stimulating and trustworthy team of supervisors.
How do you imagine your future after this thesis?
I plan to continue in public research, perhaps as a teacher-researcher, because I think teaching is something I would also enjoy. However, I remain open to other avenues; I am gradually discovering that there are many possibilities for doing research applied to conservation, for example in associations.
I would also like to have experiences abroad in order to broaden my vision of the world and of the scientific approach.
Above all, I wish to deepen this transdisciplinarity between marine ecology and sociology in my work, in order to address environmental issues that are increasingly important and worrying.
Reference : Cam Ly RINTZ, « ESPOIRS : Élaboration de bioindicateurs des estrans rocheux – Les Sciences Participatives, un dispositif d’interactions entre sciences et sociétés », thèse 2023-2026
Contact : camly.rintz@mnhn.fr