Sampling was conducted in 2008 during February, May, September and November. Six sampling
stations were selected and each was sampled once in each sampled month. Four sites
(S1, S2, S3 and S5) were situated along the main river channel, while the other two (S4 and S6)
were permanent pools. Stations S1 and S2 were located in the upstream and were commonly
characterised by clean water, and the presence of fragmented leaves, woody debris, riparian
vegetation