2016 年 21 巻 2 号 p. 47-53
To evaluate the habitat and examine comprehensive conservation measures for the freshwater type of nine-spined stickleback (Pungitius sp.1) in the Oko River basin, Sika, Ishikawa, we developed a Habitat Suitability Index (HSI) model using weighted geometric mean formulas obtained by multiple linear regression analysis. The HSI values obtained by the model revealed that the habitat qualities in four of the watercourses were superior to those in other areas. The habitat unit (HU) values also showed that one watercourse and a pond were important habitats in terms of quality and quantity. The study showed that the HSI model is a practical tool in managing the habitat for this species. In the model test, significant regression formulas were obtained between the minimum values of population density and the minimum and averaged values of HSI for each water area in the study period.
