Artificial fishways and their performances in China’s regulated river systems: a historical synthesis

Abstract

Abstract China‘s rivers are highly regulated. The biodiversity and ecosystems of these rivers are threatened by barriers restricting fish movements for reproduction and foraging. To overcome this challenge, several fishways are built across the country. However, the status of fishways is not well investigated. Based on published articles, library archives, and public interviews, we have identified type, location and period of fishways construction. We have then evaluated the performance of fishways. Up until 2018, the total number of fishways in China was estimated to be 150, where 82 of them have been analyzed in this study. The pool-type fishway is the most dominant fishway type, which accounts for 83%. The slope pattern of the 49 pool-type fishways shows that the slope tends to decrease with increasing lifting height. The performance of the fishways was best observed by the successful crossing of different species of fish in Yangtze and Pearl River basins when the slopes were 1:63–1:95. When many dams in China are already facing critical challenges for adopting the right type of fishways, the pool-type fishways with variable adjustments of slopes could be an effective option for successful fish migrations in regulated river systems.