The French National Research Institute for Agriculture, Food, and the Environment (INRAE) is a public research establishment. It is a community of 12,000 people with more than 200 research units and 42 experimental units located throughout France. The institute is among the world leaders in agricultural and food sciences, in plant and animal sciences, and is 11th in the world in ecology and environment. INRAE’s main goal is to be a key player in the transitions necessary to address major global challenges. In the face of the increase in population, climate change, scarcity of resources and decline in biodiversity, the institute develops solutions for multiperformance agriculture, high quality food and sustainable management of resources and ecosystems.
Work environment, missions and activities
the specific objectives of this thesis work are as follows:
(1) to analyze the habitat use in the broad sense of European sturgeon in the Gironde estuary;
He/She will localize individuals concentration areas and trajectories by coupling those data to habitat at different time scale (year, season) and according to ontogeny (age class, juvenile caught in the estuary are mainly between 2 and 5 years old). Thus favorable estuarine habitat for A. sturio will be characterized as well as connectivity between those habitats and social interactions. Habitat use of a sample of individuals with very different time spent in captivity before release (a few weeks versus one year or more) will be compared in order to identify if time spent in captivity has an effect on the process of habitat selection.
(2) to identify the possible interactions between the estuarine fraction of the European sturgeon population and the species present in the estuary: whether or not they share ecological niches. Thanks to this study case, at a broader scale, it will lead to thoughts of the possible interactions between re-introduced species and species already in place in the environment;
To work on objectives 1 and 2, the PhD student will be able to use Sturat database over the 2009-2019 period and acquired mainly within the frame of the French national action plan in favor of A. sturio restoration. Sturat field campaigns correspond to scheduled trawling sampling in subtidal sectors of the Gironde estuary. Trawls are geo-localized, species captured are counted and a sample of individuals are measured. Physico-chemical parameters are recorded at each trawl such as salinity, temperature, oxygen level, turbidity. Focus is made on European sturgeon population with individual tagging and tissue sampling for a posteriori analysis (genetic, stomach contents …). The PhD student will regularly participate to the current Sturat campaigns (3 to 6 campaigns of one week each per year) in order to get to grips with the methodology and be conscious of the advantages and the limits of the sampling method for the interpretation of the database already acquired he/she will work with.
A critical prior analysis of the availability of the relevant spatial and temporal environmental variables to describe fish habitat will be carried out.
To complete the analysis, the PhD student will have the choice between two options: a) if historical sampling data (1990-2000) allowed it, preferenda of wild specimen (cohorts 1994 and 1988) will be compared with preferenda of recent stocked individuals. Or b) he/she could carry out an experimentation based on picture acquisition with drone to identify if European sturgeon use the intertidal sector, currently not sampled, but that can be source of nutrients for many species. Intertidal habitat use was documented for a close species A. oxyrinchus in the bay of Fundy Canada but it has never been studied for A. sturio.
(3) to extrapolate the knowledge acquired on the habitat use of A. sturio in the Gironde to other French (La Seine) and European estuaries (Elbe, Germany) for which we have habitat data. From a theoretical point of view reflections on the future potentialities of recolonization of the species via the analysis of estuarine growth habitats use are expected.
This PhD position is part of a larger project (REVE European sturgeon life history tactics reconstruction) gathering different researchers and research laboratories. The candidate will benefit from the scientific interaction during the project.
Training and skills
The candidate will held a master degree with knowledge in population ecology, aquatic ecology, behavioral ecology or geomatics. He or she will have an experience in habitat use study for either terrestrial or aquatic species.
Skills in GIS (QGIS, ArcGis) and data base interrogation (SQL) will be strongly appreciated.
The candidate will have the capacity and the motivation to participate to field campaign on boat (one week, 3 to 6 times per year).
English proficiency will be appreciated.
INRAE's life quality
By joining our teams, you benefit from:
- 30 days of annual leave + 15 days "Reduction of Working Time" (for a full time);
- parenting support: CESU childcare, leisure services;
- skills development systems: training, career advise;
- social support: advice and listening, social assistance and loans;
- holiday and leisure services: holiday vouchers, accommodation at preferential rates;
- sports and cultural activities;
- collective catering.
How to apply
To apply, please send a detailed CV, master school results and a motivation letter explaining how your profile fit to attain the objectives detailed above. Please also expose (maximum one page) how you imagine organizing your PhD according to the 3 main objectives.