Maps of the study sites. Arrows indicate water flow direction in three rivers. Codes refer to segments of individual rivers in which surveys were conducted.

  Part of: Akamatsu Y, Kume G, Gotou M, Kono T, Fujii T, Inui R, Kurita Y (2020) Using environmental DNA analyses to assess the occurrence and abundance of the endangered amphidromous fish Plecoglossus altivelis ryukyuensis. Biodiversity Data Journal 8: e39679.