Fig 1.
Igarapava Fish Ladder (a) and its viewing window (b). The entrance (EN), observation room (OR) and exit (EX) of the Igarapava Fish Ladder (IFL) (panel a) and the viewing window (VW) of the observation room with the video camera (VC) set inside a protective housing (panel b).
Fig 2.
Number of fish species by sample unit and sample interval.
Number of fish species determined by systematic sampling of the passage of fish at the Igarapava Fish Ladder.
Fig 3.
Relationship between the linear regression coefficient (b) and sample unit.
Sample unit and b for six sample intervals for the seven most abundant fish species and species of low abundance grouped as ‘Others’ in the Igaparava Fish Ladder.
Fig 4.
Relationship between the coefficient of determination (r2) and sample unit.
Sample unit and r2 for six sample intervals for the seven most abundant fish species and species of low abundance grouped as ‘Others’ in the Igaparava Fish Ladder.
Table 1.
Metrics for the daily run-size estimation method.
Table 2.
Number of fish and b-SU relationship type per number of sampling days.
Fig 5.
Boxplot of Time Passage Deviation (TPD) per species.
TPD for the seven most abundant fish species and species of low abundance grouped as ‘Others’ in the Igaparava Fish Ladder. The closer TPD is to zero the more uniformly distributed was the passage throughout the hour (LO: L. octofasciatus, PM: P. maculatus, LF: L. friderici, SN: S. nasutus, OT: ‘Others’, PS: P. stramineus, SH: S. hilarii and PL: P. lineatus). Numbers above boxplots indicate the b-SU relationship type. Boxplot shows median, interquartile interval and non-outlier range.
Fig 6.
Influence of fish abundance on the interquartile interval of Time Passage Deviation (TPD) and Daily Sampling Duration (DSD).
Regressions showing the influence of fish abundance on TPD (A) and DSD (B) for the seven most abundant fish species and species of low abundance grouped as ‘Others’ in the Igaparava Fish Ladder. Asterisk indicates linear regressions with a significant slope.