Telomeres: a molecular biomarker for assessing the status of seabird populations?
As apex predators, seabirds have important roles in maintaining healthy marine ecosystems. However, seabirds around the world are facing a wide range of environmental stressors, such as global warming, habitat degradation and fishery bycatch, and many seabird populations are in decline. Traditionally, it is time-consuming to identify declining populations because it requires years of collection of demographic data. Recently, some studies found that longer telomeres, the non-coding DNA repeat regions located at the ends of chromosomes, are associated with higher individual quality. This led to the proposal that the length of telomeres, could be a promising molecular biomarker to assess the quality of individual animals and hence the population trend of wild vertebrates. Based on this idea, my thesis aims to test whether the telomere length can be used to assess seabird population trends.
Although telomeres are inexorably shortened over an individual’s lifetime, it does not follow a linear pattern: the shortening rate is faster during the development stage compared to the adult stage and can be accelerated by many factors, such as lifestyle and stress. Therefore, to validate whether telomere length can be a reliable diagnostic tool for population trends, we need to first answer some questions about telomere dynamics: 1) what factors can affect the variation in telomere length and shortening dynamics within and among individuals during their development and adult life, and 2) the relative importance of these factors in different life stages to the telomere length of an individual.
In my thesis, I aim to answer these questions by studying the telomere dynamics of a range of seabird species in the Arctic and the French Southern and Antarctic territories (TAAF). These populations have been monitored for decades in both breeding and/or wintering seasons, providing data about both the birds’ developmental condition and adult life. With those questions addressed, I will move on to validate the efficacy of the telomere length as a diagnostic tool for seabird population trends by comparing the average telomere lengths of populations with different demographic trends (stable, increasing or decreasing population size).
PhD student in the ECOPHY team (2023-2026)
Supervisors: Frédéric Angelier, Christophe Barbraud, Olivier Chastel
Doctoral school: EUCLIDE (La Rochelle University)
Funding bodies: La Rochelle University, IPEV, ANR
Mail: jingqi.liu(at)cebc.cnrs.fr
