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Keywords:

  • Diffusion model;
  • diffusion rate;
  • habitat fragmentation;
  • harmonic radar;
  • mark-release-recapture study;
  • population cage;
  • temperature-dependent dispersal

1. Habitat fragmentation may lead to natural selection on dispersal rate and other life-history traits. Both theoretical analyses and empirical studies suggest that habitat fragmentation may select either for increased or decreased dispersal depending on the traits of the species and the characteristics of the landscape.

2. Dispersal and movement rates in Glanville fritillary butterflies (Melitaea cinxia) originating from a continuous landscape in China and from a highly fragmented landscape in Finland were compared using three different methods.

3. The methods included replicated mark-release-recapture (MRR) experiments conducted in the natural environments in China and Finland, tracking with harmonic radar of captive-reared but free-flying butterflies in a common environment in the field, and replicated common garden experiments in a large outdoor population cage.

4. The results were largely consistent, showing that butterflies from the more continuous landscape in China had a lower movement rate than butterflies originating from the fragmented landscape in Finland. Butterflies originating from newly-established populations in Finland moved significantly longer distances than butterflies originating from old populations in Finland or from China, demonstrating significant intra-specific variation in dispersal rate in Finland. These results are consistent with model predictions for the Glanville fritillary.

5. The tracking experiment revealed a result that would have been impossible to obtain with MRR experiments: movement rate was influenced by a significant interaction between population origin (China vs. Finland) and ambient air temperature.