Physical fragmentation of river networks via dams and other water control structures alters the natural flow regime. This alteration often results in a change or loss of ecological function, impacting many freshwater aquatic species, particularly riverine habitat specialists. Many rivers in Australia and elsewhere have been the subject of significant hydrological and physical change over the last 100 years. An abundance of research has been conducted to assess the effect of physical fragmentation in river networks on the fish community. A systematic literature review was undertaken to identify existing published literature about the effect of fragmentation on fishes while minimising selection bias. Qualitative information from the existing literature was synthesised and mapped, showing that there is a scarcity of interdisciplinary research focused on long term functional changes in fragmented rivers, especially those located in arid climates. The existing literature was further analysed to elucidate how fragmentation in dryland rivers has influenced two measures of ecosystem function. The Eco Evidence method was used to extract evidence from the existing literature, allowing for the inclusion of multiple study designs. Initial results indicate that there is insufficient evidence to assess the relationships between physical fragmentation and food web dynamics and gene flow in dryland rivers.