Description du sujet de thèse

The SymbioCues project aims to precisely characterise the start of symbiosis between corals and their most abundant bacterial partners. Understanding how coral associated bacteria become symbiotic is not only essential for the health of juvenile corals, but is also be important for understanding the re-establishment of symbioses in adult corals following environmental stresses. These results will also help to elucidate the long-term impact of manipulating the coral microbiome and how these approaches can be used to slow the current degradation of coral reefs.
The candidate will be required to:
o Set up a research project to characterise the onset of the coral-bacteria symbiosis.
o Carry out aquarium and laboratory experiments to monitor the colonisation of corals by bacteria.
o Write a PhD and scientific publications.
o Present the results within the university and at conferences.

The expected skills are:
• Expertise in microbiology, molecular biology and genetic engineering
• Competence in the implementation of field and laboratory experiments
• Ability to set up a research programme (drafting a thesis proposal, literature review)
• Good statistical analysis skills to develop appropriate scientific protocols and analyse data
• Experience in invertebrate aquaculture
• Ability to work as part of a team

Contexte de travail

Tropical coral reefs are some of the most productive marine ecosystems, providing ecosystem services to over 500 million people worldwide. Although they cover only 0.2% of the seafloor, they are home to 25% of all marine species. However, in the past three decades, coral reefs have come under increasing pressure from overfishing, declining water quality, rising temperatures and acidification, all of which have hampered ecosystem functioning and led to the loss of essential ecosystem services. To improve the resilience of coral reefs to environmental stressors, we need to understand the mechanisms underlying coral health.

Corals are home to an astonishing diversity of micro-organisms, the most abundant of which are endosymbiotic microalgae and bacteria. These micro-organisms exchange nutrients with their hosts and are essential to their health and to the ecosystem they support. Despite the strong interactions between corals and their microbial symbionts, over 70% of coral species do not pass on their symbionts to their offspring, which must be acquired from the environment.

Contraintes et risques

The PhD will take place mainly in a laboratory environement (molecular biology, microscopy) in Perpignan and will include the isolation, identification and use of symbiotic bacteria associated with corals. Field trips, lasting approximately one month, will take place each year in Mo'orea, French Polynesia.