Department Fish Ecology and Evolution

Within the current biodiversity crisis, intraspecific genetic diversity has been declining globally. Yet, genetic diversity is key for species persistence, their ability to adapt to changes in the environment, fight disease and recover after an ecosystem disturbance. To quantify and halt this loss, policies for management and restoration efforts that incorporate and track suitable indicators of intraspecific genetic diversity are necessary.

Our project aims to provide a global assessment of the levels of intraspecific genetic diversity of the different species that comprise the Alpine whitefish radiation. Alpine whitefish (Coregonus spp.) are key components of the aquatic biodiversity of Alpine lakes, having colonized and diversified in the lakes after the last glacial maximum (10-15 thousand years ago), resulting in a large diversity of over 30 species. However, Alpine lakes have been severely impacted by human activities. Eutrophication, the introduction of invasive species and in some cases fishing pressures have greatly impacted Alpine whitefish, resulting in fishing stock crashes and the extinction of 10 endemic whitefish species. How these factors affected the genetic diversity of the remaining whitefish species is unknown. Yet, this is key information to evaluate the species current status and define management and recovery strategies for the future.

In this project, we will evaluate the historical and contemporary effective population sizes (a measurement of intraspecific genetic diversity) of the different Alpine whitefish species. We aim to establish a baseline for the historical genetic diversity of whitefish prior to anthropogenic disturbance and provide information on their current effective population sizes. This information can be integrated into future management and recovery plans. In collaboration with the FOEN and cantonal authorities, we will also develop a panel of genetic markers suitable for species identification.