“…In the Amazon Basin, thousands of small dams are operating and acting as physical barriers to fish movement ( Freitas et al, 2022 ). Blocking movement between upstream and downstream stretches, small dams can alter the composition and trophic structure of fish assemblages in Amazonian streams ( Sousa et al, 2018 ). These changes in the fish assemblage in turn influence the prey-predator relationships, the fish prey composition, and overall resource availability for predatory fish.…”