ENHANCE-M1

Catching dragonflies at a ditch in the Oberaargau region: a typical habitat for the damselfly Coenagrion mercuriale. Photo: Daniela Keller

Marked damselflies for the investigation of dispersal behaviour. Photo: Daniela Keller

Gomphocerhippus rufus, one of the four grasshoper species investigated. Foto: Wikipedia

Typical grasshoper habitat - intensively used agricultural landscape. Foto: Daniela Keller

As the Swiss plateau is dominated by large-scale intensive agriculture, a lot of insect populations got fragmented or even disappeared completely. Within the CCES project ENHANCE, the connectivity of fragmented but also of de-fragmented populations is investigated for several examples. Does individual exchange and gene flow occur between population fragments? What landscape structures are used as connectivity elements and what structures act as barriers? Are measures of de-fragmentation successful? Using mark-resight studies, genetic methods and landscape analyses, we investigate dispersal of several insect-species. For instance, we are looking at a rare damselfly (Coenagrion mercuriale) that colonises ditch systems in the midst of intensively managed agricultural areas in the Oberaargau region. Another subproject deals with four grasshopper species with different habitat needs but typical for agricultural areas (Chorthippus biguttulus, Gomphocerhippus rufus, Chorthippus albomarginatus und Chorthippus brunneus). 

• Rolf Holderegger
  

• Daniela Keller