Fig 1.
Distribution of Weirs in Zhejiang Province, China.
(a) Provincial-scale map; (b) Majinxi River Basin (the sampling site for experimental fish); (c)Yong’anxi River Basin. Base Map Source Attribution: The base maps in this figure were generated using elevation data from the ASTER Global Digital Elevation Model V3 (ASTER GDEM v3; NASA/METI, https://doi.org/10.5067/ASTER/ASTGTM.003) and the NASA Shuttle Radar Topography Mission Global 1 arc second V3 (SRTMGL1 v3; NASA/JPL, https://doi.org/10.5067/MEaSUREs/SRTM/SRTMGL1.003). These datasets are publicly available through the NASA Earthdata platform (https://earthdata.nasa.gov/). Data gaps in the ASTER GDEM were filled using SRTMGL1 v3 data.
Fig 2.
Configuration of the experimental setup (Unit: cm).
(a) Plan view; (b) Section view.
Table 1.
Passage success rate of A. fasciatus at successive weir stages.
Fig 3.
Passage success rate (PSR) of A. fasciatus at three successive weir stages across four body length classes.
Bars represent the mean ± standard deviation (SD) of the two biological replicate trials within each body length class. All inferential statistical analyses in this study are based on the 8 independent trial group values (4 classes × 2 replicates).
Fig 4.
Photographs of A. fasciatus during upstream passage attempts.
(a) PLS; (b) LSS. Leaping individuals are marked with red circles.
Table 2.
Proportion of passage strategy usage of A. fasciatus at the first weir, by body length class..
Fig 5.
Relationship between mean body length per trial group and the proportion of PLS/LSS usage.
Each data point represents one of the 8 independent trial groups. All linear regression analyses are based on these 8 independent data points..
Fig 6.
Behavioral parameter analysis of upstream migration in A. fasciatus of different body lengths.
(a) (b) Relationship between body length and takeoff position; (c) (d) Relationship between body length and leap distance; (e) (f) Relationship between body length and leap height. Each data point represents one of the 8 independent trial groups, showing the mean body length and median kinematic value for that group. All linear regression analyses (trend lines) are based on these 8 independent data points, with R² and p values reported in the text.
Table 3.
Statistics of swimming (Sprint) distance within the leaping-swimming strategy for A. fasciatus of different body lengths.
Fig 7.
Schematic of weir crest profile and pool layout.
(a) hydraulic head drop; (b) pool depth; (c) inter-weir pool length).