The Relation between Ecology of Fiddler Crabs (Genus Uca) and Hydraulic and Mud Property

Abstract

The ecological investigations on fiddler crabs (Genus Uca) have been conducted on the Sumiyoshi tidal flat in the Yoshino river mouth from 1993. This flat is one of a paradise of Uca arcuata and Uca lactea lactea which are specified to the rare species on the reddata book. This paper reports the results of inhabitant surveys of crabs (which include 1) active individual densities, 2) mud properties at their habitats, 3) sampling of crab larvae) and numeric calculation of the dispersion process of the crab larvae just after the larval release.