Author(s): Kouki Onitsuka; Juichiro Akiyama; Kousuke Izumi
Keywords: No Keywords
Abstract: Studies on biology and environment of eels (Anguilla japonica) have been advanced in recent years. However, little is known about fish ladder for eels and migrating characteristics of eels. Especially, special fishways are necessary for demersal fish like young eels. This study was made to evaluate effects on migration rates of eels under the condition that diameter of protrusions and discharge per unit width in fish ladder are changed. It was found that migration rates increase with the increase of discharge per unit width in each diameter of protrusions. Besides, the sinuosity of eels is increasing, and the averaged migrating speed is decreasing with the increase of discharge per unit width and diameter of protrusions.