Marie-Elodie Perga

National Institute for Agronomical Research
Alpine Research Center for lake food webs
75 Avenue de Corzent, Thonon les Bains, France
perga@thonon.inra.fr

Everything you can do with Whitefish when you’re not a fish biologist

The whitefish Coregonus lavaretus (L.) constitutes the major fisheries resource in French subalpine lakes. In addition, as a zooplanktivorous predator, whitefish occupy the top position in the pelagic food web of these lakes. I hence use whitefish as a model species to study carbon and energy fluxes within the pelagic food web using trophic biomarkers such as C and N stable isotopes and fatty acids.

Here, I provide examples of how C stable isotope and fatty acid measures on whitefish tissues can document C sources fueling the pelagic food web of contemporaneous lake ecosystems. Many limnology labs have extensive collections of archived fish scales. I also show that C stable isotope measures can be performed on archived fish scales to investigate retrospectively how human perturbations have altered C cycling in lakes.

Besides, whitefish was introduced in the late XIXth century in some of these French subalpine lakes. Combining paleo-limnology and stable isotope methods, I also study the impact of whitefish introduction on lake food webs over the last 120 years.

Ort

07.05.2009 15:00 Uhr

Großer Hörsaal
Müggelseedamm 310
12587 Berlin-Friedrichshagen 









© IGB 5/8/2009