Key interests: Evolutionary Ecology and Genetics, Diversification of Fishes, Adaptation, Adaptive Radiation, Applied Evolutionary Biology

Characterization of natural variation in North American Atlantic salmon populations at a locus with a major effect on sea age

Louis Bernatchez (Supervisor)

I am interested in evolutionary ecology and adaptive speciation processes in fishes. For my doctoral work I focused on eco-evolutionary divergence based on color and trophic polymorphisms in cichlid fishes from Neotropical volcanic crater lakes and Lake Tanganyika (Africa). I investigated how such polymorphisms originate, how they are maintained, and under which circumstances they might lead to speciation. For example, in the Nicaraguan Midas cichlid system (Amphilophus spp.) I studied parallel sympatric divergence along i) the benthic-limnetic axis and ii) based on a color polymorphism. I also focused on the morphological and behavioral laterality of the African scale-eating cichlid Perissodus microlepis that is well known for its asymmetric (left or right oriented) mouth morphologies and tested key hypotheses surrounding its laterality and the maintenance of the left-right mouth polymorphism.

In addition to my interest in fish evolution, I wish to contribute to the sustainable use of aquatic resources by fisheries and aquaculture. For decades the fishing pressures on natural populations and the proportion of fish raised in aquaculture has increased dramatically. Consequently, a thorough understanding of the mechanisms ensuring biodiversity in exploited fish populations is crucial for the future availability of this valuable aquatic resource.

For my postdoctoral work in Louis Bernatchez`s lab (starting in October 2015) I will characterize the genetic variation at a major sea age locus across multiple North American Atlantic salmon (Salmo salar) populations. Sea age refers to the number of years an individual spends in the marine feeding grounds at sea before returning to its home river to spawn. From an economic perspective, sea age is important because it is directly linked to body size, and is thus of particular interest for the fisheries management of exploited salmon populations. Moreover, from an evolutionary perspective sea age is of great interest to study sexual conflict, i.e. in Atlantic salmon females usually have higher sea age than males as a consequence of different reproductive strategies between sexes.

The project is done in close collaboration with Craig Primmer’s group from the University of Turku (Finland) and with partners in two governmental institutions (Ministère des Forêts, de la Faune et des Parcs & Fisheries and Oceans Canada).

For this project, I am developing a Next Generation Sequencing (NGS) assay to infer SNP markers diagnostic of sea age at the individual level, at the population level and over time. Given the broad biological implications of this trait, my work will potentially contribute to an improved fisheries management of this iconic fish species.

For links to my publications, please go to: https://scholar.google.de/citations?user=RtdJYqYAAAAJ&hl=en