This study shows that patterns in some community assemblages are not mainly governed by local factors but also by regional ones. Using field data from 36 floodplain forest lakes in the Amazon basin, we present transect count data on the richness, abundance and distribution of floodplain lake fish species. A total of 194 fish species were collected, of which 43 were classified as short-distance migrants. A positive relation was found for local migratory and sedentary species abundances with distribution at a regional scale. The study also suggests that the probability of the presence of a migratory species is more affected by aspects of river-lake connectivity than sedentary species. Our results seem to indicate that migratory species play an important role in local dynamics of floodplain lakes.