Présentation

Aim

The main objective of the research in polar environments, carried out at LEA, is to evaluate the adaptation capacities of the king penguin (Aptenodytes patagonicus), Adelie (Pygoscelis adeliae) and Emperor (Aptenodytes forsteri) to global changes, through the study of functional mechanisms and micro-evolutionary processes.
Our exceptional non-banding database allows us to study the links between environmental variability (climatic and trophic) and the survival, as well as phenology and reproductive. We also focus on foraging performance of different cohorts of penguins, according to their age, status, experience or other phenotypic traits (morphological, physiological and behavioural; traits whose plasticity and heritability are studied).
We also study the spatial structuring of colonies according to different constraints (parasitism, predation, local weather conditions, etc.) using robots and cameras, as well as the structure, diversity and gene flow between colonies and archipelagos.
Eventually, retrospective and prospective analyses will allow us to evaluate population demographic trends according to climate scenarios.
                                                          

Impact of climate change on biodiversity

One of the major questions raised by climate change scenarios for the coming decades, concerns their impact on biodiversity. We will be more able to determine the various threats to species, if we know their capacity to adapt and their limits in the face of environmental changes, whether natural or anthropogenic.
However, the consequences of climate change on biodiversity, like those related to other anthropogenic impacts (population growth, invasive species, overexploitation of resources, etc.), are difficult to predict because of the complexity of systems and require a multidisciplinary and integrative approach. The impact of the environment is exerted on the different levels of biological organization, and these levels respond in a unique and potentially non-linear way to variations in their environment.
Environmental changes modify the phenotypic traits of individuals, the life history strategies of populations and species, and delimit new ranges, while altering their abundance and distribution. The composition of communities, as well as the structure and functioning of ecosystems are, consequently transformed.

 

The Polar Ecosystem

In the context of global changes, the study of polar ecosystems is crucial because they show a vulnerability to these changes that is much more intense than other ecosystems. The Southern Ocean plays a key role in the regulation of the global climate, because it transmits climatic anomalies between the major oceans.
This circumpolar ocean is home to one of the most productive ecosystems on our planet, with marine primary production accounting for about 15% of global marine production. It is also the main breeding and feeding area for a large number of seabirds of the order Procellariforms and Spheniciforms. As the trophic chains of the Southern Ocean are relatively short, a change occurring at their base has very quickly detectable consequences at higher trophic levels. These indirect effects on the abundance and distribution of prey ('Bottom-Up control'), therefore have rapid consequences on the selective value of organisms via the mechanisms of food search and resource allocation.
Demographic studies have shown that seabird populations in the Southern Ocean are strongly affected by climatic anomalies. Demographic studies have highlighted the worrying of most of these populations, and strongly suggest that, because of their sensitivity, the ecosystems of the Southern Ocean are undergoing a major change. Therefore, understanding and predicting the effects of global changes on these marine ecosystems is a unique and fundamental scientific and technical challenge for our society.

 

Research themes

  • Behavioural and evolutionary ecology
  • Population dynamics and demography
  • Biostatistics and modelling
  • Population genetics seabirds