The role of asymmetric dispersal in metapopulations

Conference poster, 2009

Metapopulations consist of a number of sub-populations connected through the dispersal of migrants. In many theoretical approaches often rather simple dispersal patterns are investigated, while typically complex dispersal patterns are observed in nature. This especially is the case for larvae dispersal in marine environments driven by ocean currents. In a recent work Vuilleumier and Possingham investigate the role of symmetry in dispersal patterns and draw the conclusion, that asymmetric dispersal has a distinct negative impact on population viability. Our results based on artificial dispersal patterns, however, suggest that symmetry actually only could have a vanishing impact. The simulation results are in good agreement with tests on realistic dispersal patterns of mussel larvae in the Baltic Sea. We demonstrate the importance of artificially generated dispersal patterns for the disentanglement of the complexity intrinsic to natural systems. Although many aspects of larvae dispersal might not yet have been understood we can draw the conclusion, that asymmetry might not be as severe as expected by Vuilleumier and Possingham. That is of course good news for many systems of biological relevance.