Author(s): E. Mitsuteru; Atsushi Kawachi; Tadaharu Ishikawa
Linked Author(s):
Keywords: Tidal flat; Lagoon; Crustacean; Burrow; Habitat
Abstract: AMPARU is a large tidal lagoon located on the west coast of Ishigaki Island, where a variety of small crabs range over. In these thirty years, however, accumulation of red clay from the farmland has been changing the topography and the hydraulic characteristics of the lagoon, and then changing the environments for the crabs to habitat there. This paper presents a result of a field survey that is the basic stage of a study to understand the spatial distribution of crabs in relation with the conditions of bed materials and hydraulic characteristics in the lagoon. First, spatial distribution of five kinds crabs are clarified through quadrat survey. And then, it is found that the habitat distribution of each kind of crab can be highly related to their living characteristics, such as territorial competition, seasonal torpor and efficiency of nutrition as well as environmental conditions such as grain distribution of bed materials, organic matter content and submergence frequency.
Year: 2005