2.2 Sampling design
The study area covered approximately 15 km of the river with a total of 3 sampling points. This sampled section is invaded by O. niloticus . At each sampled site a total of three (3) sampling points were selected with a river distance of about 7.2 km apart. Each sampling point had a total of 200 meters stretch covered encompassing all the available five (5) microhabitat type (runs, riffles, vegetative thicket point, open pool (near fisheries landing area) and the tributaries. Sampling of the fish was conducted in the entire 5 selected aforementioned habitat present in each sampling point. Therefore, a total of 3 sampling points with 15 microhabitats were sampled in the sections of the upper Kabompo River from December 2019 to June 2020.
The studies by Bok and Bills (2012) and DoF (2018) showed that the sampling points have a greater similarity in presence of the exotic and native fish species, rainfall pattern, environmental condition and general water flow regime despite the unique natural barrier that separates them. Due to the proximity of the sampling points, it made the two points of the river easer for exploring their dietary preferences.