The catfish Trachelyopterus striatulus Steindachner, 1877 is a very abundant fish species in reservoirs in Southeast Brazil, and its relative abundance seems to be increasing in several lentic environments. Despite of being a very common species, few information is available on its distribution and other aspects of ecology. The Lajes reservoir (22º42'-22º50'S e 43º53'-44º05'W) is the largest manmade lake for hydropower purposes in Rio de Janeiro State, where this species rank among the top abundant fishes, both in number and in biomass. Its relative abundance were compared in three zones of the reservoir (upper, central and lower), based on a standardized program, during three annual periods (monthly sampling in 1994 and bi-monthly sampling in 1996 and... |