2026-10-11T19:37:40Z https://api.figshare.com/v2/oai

oai:figshare.com:article/33970828 2026-09-23T05:17:28Z category_30187 item_type_3 month_year_09_2026

<b>Localized Flow-Coupled Return Behavior in Stream Fish: Underwater Video, Fish Trajectories, and Natural-Tracer Flow Data</b> Osuke Doijiri (24913549) Biological physics localized flow-coupled return behavior fish-flow interaction stream fish station holding natural tracer optical flow underwater videography stream hydrodynamics <p dir="ltr"><b>This dataset contains raw underwater video and derived trajectory and image-motion data documenting a field observation provisionally termed localized flow-coupled return behavior (LFCR) in small stream fish.</b></p><p dir="ltr"><b>Seven fish trajectories were visually confirmed from the underwater recording. Four trajectories met an operational return criterion, whereas three were classified as transit-type trajectories. In all four return-type trajectories, the principal direction of fish displacement reversed between the outward and return phases. Image motion of naturally occurring particles surrounding the fish was independently analyzed as a proxy for local flow, and the direction of this local motion proxy also reversed between phases in all four return-type trajectories.</b></p><p dir="ltr"><b>The dataset includes the original underwater video, normalized fish trajectories, frame-level natural-tracer motion estimates, outward–return phase analyses, off-fish spatial controls, exploratory fish-centered optical-flow and vorticity analyses, derived figures, and documentation required to interpret the analysis.</b></p><p dir="ltr"><b>LFCR is used here as an </b><b>operational descriptor of an observed spatiotemporal pattern</b><b>, rather than as an established behavioral category. The hydrodynamic variables are derived from two-dimensional image motion and are expressed in image-coordinate units; they are not calibrated measurements of physical water velocity. The data therefore provide a hypothesis-generating record for investigating localized coupling between fish movement and naturally occurring flow fluctuations in a stream environment.</b></p><p><br></p> 2026-09-23T05:17:28Z Dataset Dataset 10.6084/m9.figshare.33970828.v1 https://figshare.com/articles/dataset/_b_Localized_Flow-Coupled_Return_Behavior_in_Stream_Fish_Underwater_Video_Fish_Trajectories_and_Natural-Tracer_Flow_Data_b_/33970828 CC BY 4.0