Post-doctorate : investigation of individual migration histories of sea bass in Bordeaux

IFREMER, centre de Brest, France

Job Location
IRSTEA Bordeaux, France

Anticipated start date and duration
2 April 2018, 18 months

Scientific context
European sea bass, Dicentrarchus labrax is, especially in France, a key species for both recreational and commercial fisheries. Recent stock assessments have shown a decline of sea bass wild population which spatio-temporal structure remains poorly understood. In this context, the European Maritime and Fisheries Funded (EMFF) BARFRAY project aims at analyzing the connectivity between spawning areas, nurseries and habitats used by adult fish. Connectivity between habitats across life cycle is a key issue for the comprehensive understanding of population dynamics and seeks at targeting more accurate management and species conservation actions in space and time.
Since 2010, Ifremer has carried out large-scale electronic tagging programs targeted on adult fish that have already provided more than 400 recoveries. The individual migration histories reconstructed from the recovered data storage tags has yield evidence of fidelity to both summer feeding areas and winter spawning areas. Key results for understanding the spatial structure of the population are expected from coupling for the same fish, migration histories obtained from data storage tags and the analysis of individual histories of earlier life stages (larvae and juveniles) retrieved from calcified structures.
One of the tasks of the BARFRAY project aims at reconstructing natal origin and migration histories by analyzing calcified structures using different chemical tracers (trace element and stable isotopes). Calcified structures were already collected on tagged fish on several occasions (scales collected at initial tagging; otoliths and scales on recoveries). This investigation is addressing 1) the geographical origin of the recoveries (where born?) 2) natal homing (do sea bass present such behavior?), 3) migration strategies between essential habitats during the life cycle (connectivity between spawning areas, nurseries and feeding areas occupied at the adult stage).

Job description and missions
The post-doctorate fellow will be in charge of the investigation of individual migration histories of sea bass recovered from the tagging programs. This study will be conducted using chemical analysis of calcified structure (otoliths and scales) of European sea bass that had been tagged with data storage tag. Interactions between the other tasks of the project are expected in order to couple the information inferred from calcified structures with other sources of information, most importantly migration patterns that have been inferred from DST data.
The missions of the post doc will be the following:
1) Selecting relevant samples to address the different questions of the project
2) Supervising (and contributing to) the sample preparation
3) Conducting the chemical analysis in collaboration with IPREM laboratory in Pau University (trace element analysis) and UMR EPOC in Bordeaux University (stable isotope analysis )
4) Analyzing the chemical data based on robust statistical approach
5) Writing reports and at least one peer reviewed paper
6) Presenting the result in one international conference

The candidate is expected to have a hands-on experience of working with calcified structures of fish or aquatic animals and microchemical analysis (trace element and stable isotope analyses). Strong statistical background is expected, and an experience with microchemistry/geochemistry data and time series data treatment will be appreciated. Autonomy, aptitude for networking, open-mindedness and motivation, as well as good English speaking/writing skills, are also expected.
Position context
The postdoc will join the EABX research unit at IRSTEA Bordeaux (Cestas) and will be managed under the authority of IFREMER
The position will be for an initial duration of one year, renewable for 6 months provided satisfying achievements. Salary is about 2100 -2400 € net/month, depending on the candidate’s experience.

How to apply
In order to apply for this post, a folder that contains a CV, motivation letter, resume of the previous work including thesis and any prior postdoctoral positions, a complete list of publications, as well as letters of recommendation, should be sent.
Application email: francoise.daverat &

Application deadline: Saturday 10 February 2018