Density and characteristic of bioturbation of Uca spp at Tanjung Tiram mangrove ecosystem in Poka village, District of Ambon Bay

Abstract

Mangrove ecosystem provides high ecological contribution to various biological resources including fiddler crab, Uca spp in its ecological and economic role in the ecosystem. The study held in September to October 2020 to analyze species composition, density and characteristic of bioturbation (color, substrate structure and the shape). The study was conducted at 3 station using purposive sampling method. The stations are determined based on the characteristic of the fiddler crabs habitats (living status, the vegetation of mangrove, substrate tipes and utilization level). Three species of fiddler crabs are found in the study namely Uca perpelexa, U. lactea, and U. mjoebergi. The highest density is represented by U. perpelexa. The highest density of fiddler crab is found in station 2 with various habitats characteristics. The color of the bioturbation are different in every station considering the substrate structure. Substrate fraction is dominated by sand in various catagories in every station especially on its roughness (rough, medium and soft). Five shapes of bioturbation are found by the study considering the various percentage of total and the various of inhabitant species in every station. The bioturbations are influenced morfologicaly by substrate structure and the existing rooting of the mangrove vegetation.