Marie-Lee Castonguay

Ph.D. candidate

Supervisor: Valerie Langlois
Louis Bernatchez, Université Laval
Start: 2021-09-06
End: 2025-05-31


The ecology of environmental DNA (eDNA) and environmental RNA (eRNA) for wildlife tracking in a changing climate
A fundamental objective of the conservation and management of aquatic fauna is to carry out effective monitoring of biodiversity in order to obtain an accurate knowledge of the distribution and abundance of species. The analysis of environmental DNA (eDNA), i.e. the genetic material released by organisms into their environment, makes it possible to indirectly detect the presence of a species and to estimate its relative abundance in an environment. , from any environmental sample. For example, with a simple sample of water taken from a lake, it is possible to detect the presence of animal species that are at risk, invasive, harmful and important from a cultural and economic point of view. It is therefore a very promising method providing a large number of precise and non-destructive data for the species studied and its environment. Another innovation that will be exploited during the project is the use of environmental RNA (eRNA) as a potential way to assess the viability of the target organism and its recent presence. Indeed, the rapid degradation of RNA compared to DNA is an advantage insofar as its detection can be attributed to the presence of a living organism which has recently passed through the sampled site. The future of biomonitoring using eDNA and eRNA, however, must overcome the current limitations of the method in order to reach its full potential. For example, understanding the factors that can affect the detection of these two molecules represents a challenge in the use of eDNA and eRNA analysis tools and can greatly influence the interpretation of data collected in the field. Compared to the growing number of studies showing the effectiveness of eDNA analysis for biomonitoring, relatively few focus on eDNA ecology as well as eRNA. The project aims to study the ecology of eDNA, but also of eRNA under changing conditions. In other words, different biotic or abiotic factors will be studied in the laboratory in order to understand the impact they have on the production and degradation of eDNA and eRNA in species of interest. Thus, a better understanding of the ecology of eDNA and eRNA can help in a better applicability and interpretation of the results during the analysis of samples collected in the field.


ADN environnemental, ARN environnemental, Environnement, Faune, Biologie moléculaire, Espèces d'intérêt, Espèces aquatiques, Outils moléculaires, qPCR, Écologie de l'ADN et de l'ARN environnemental