Preliminary analysis of the construction and operation status of fish passage facility in China

Over the past 60 years, fish passage facilities have been extensively constructed in China. To evaluate their construction and operational status, we developed a comprehensive database of 211 facilities, including 172 completed and 39 incomplete as of 2023, and conducted a literature review encompassing operational records for 18 facilities. Firstly, the results reveal three distinct phases in the development of fish passage facilities in China (1960–1980, 1981–2004, and 2005–2023), supported by quantitative evidence. The dataset clearly illustrates the construction status of these facilities across the country. Secondly, vertical slot type fishways emerged as the most prevalent type, accounting for 48.1 % of the 201 facilities with known types, while newer facility types, such as fish lifts and nature-like bypass channels, began construction only after 2010. The geographical distribution of facilities is notably uneven, with the Yangtze River Basin hosting the highest concentration. Thirdly, compared to the construction data, operational records for facilities in China remain scarce. Among the 18 projects reviewed, operational records from 9 facilities indicate that only some primary target species utilized the facilities, whereas numerous non-target species were successfully observed. This highlights the significant ecological role of fish passage facilities in promoting fish connectivity and biodiversity. Finally, there is a clear and growing demand for the continued construction of fish passage facilities in China. To enhance their effectiveness, it is recommended to establish a standardized evaluation system during their operational phase and to prioritize the downstream migratory needs of fish, as information on this aspect remains insufficient.