Habitat characteristics and potency of mud crabs Scylla serrata, S.transquaberica, and S.olivacea in Cibako Mangrove Forest, Sancang, Garut Residence, West Java

Abstract

The research was conducted in August - November 2011. The site contains six stations, each station in three zones. Station 1 and 2 was placed in zona A where zone A in the front area of mangrove forest. Station 3 and 4 was placed in zone B that location in the middle of mangrove forests. Station5 and 6 was placed in zone B where location in behind the mangrove forest. This study aims to obtain data and information on the habitat characteristics and potency of mud crab based on the existence of species, abundance, and size distribution. The method used was a survey. Observations of habitat characteristics performed in-situ by the method of sampling transect line plot. Cluster evaluation of habitat characteristic used cluster analysis. Analysis of habitat characteristics with potency of mud crab used correspondence analysis. The results showed that the parameters of habitat 1 and 2 had been similarity, and this was classified as groups of zone A. The similarity of parameters in station 3 and 4 were classified as group of Zone B, and the similarity of parameters in stations 5 and 6 were classified as group of zone C. S.serrata dominated in zona A where the substrat were mud with range of salinity between 24 – 30 ppt, totaled 73 ind. S.tanquaberica dominated in zone B where the substrat were mud with range of salinity between 22 – 25 ppt, totaled 94 ind. S.olivacea dominated in zone C where the substrat were clay with range of salinity between 18 – 23 ppt, totaled 45 ind. The abundance of mud crabs were in dark moon, where totaled zona A was 57 ind, zone B was 68 ind, and zone C was 32 ind. Mud crabs had possess of negative phototactic, because the habit of mud crab often refuge and hiding on a substrate that was not exposed to light directly. The high density of mangroves were found in zona A and B. which Third of mud crabs associated with mangrove that had density so higher. The average of litter weight as source of food for macrozoobentos, each which of was 200.72 g and 204.83 g. The average of macrozoobentos abundance, each which of was 13 ind/m2 dan 17 ind/m2 . Therefore, mud crabs would interest to settle in zone that had abundance of macrozoobentos as source of food.