Dispersal rates and distances in adult water frogs, Rana lessonae, R. ridibunda and their hybridogenetic associate R. esculenta

摘要

Abstract: I investigated dispersal of adult water frogs between local ponds containing Rana lessonae, R. ridibunda and their hybridogenetic associate R. esculenta. Recent models indicate a strong influence of species specific dispersal on the dynamics of such mixed populations. However, empirical data on dispersal are still rare and populations are often defined through individuals which reproduce at the same site. In my study area near Zurich, Switzerland, 12.2% of the animals changed ponds in 1995 and 1996. Dispersal occurred throughout the whole year and was not restricted to specific periods. The dispersal rate decreased with increasing pond-to-pond distance and degree of isolation. In addition, I found differences in dispersal rate and distance related