Spatial distribution and habitat preferences of the Japanese eel, Anguilla japonica, at the reach and channel-unit scales in four rivers of Kagoshima Prefecture, Japan

Catches of Japanese eels have been decreasing at an alarming rate and extinction of wild stocks is of concern. Therefore, conservation of eel habitats has become increasingly important. Here, we analyzed the habitat preferences of Japanese eels using generalized linear models from the relationships between presence/absence or population density with physical environmental factors. The models suggested the characteristics of preferred habitats that should be conserved. In the tidal reaches, the densities of small eels (