Size distribution, growth pattern and condition factor of mangrove crab Scylla serrata in the coastal waters of Western Seram, Maluku, Indonesia

Research to study size distribution, growth pattern and condition factor of mangrove crab Scylla serrata was conducted on September 2013 to April 2014 in the coastal waters of Western Seram. Samples of mangrove crab was collected by using trap from four locations namely Wael, Masika Jaya, Kasuari island dan Manipa island. Width of carapace of the mangrove crab collected was measured and then weighted without separating the sex. A total of 451 individuals of mangrove crab were collected during the study with the carapace width ranging from 10.5-21.3 cm (mean= 15.61 cm; SD=2.19 cm), while the weight ranging from 200 - 2200 g (mean= 759.4 g; SD = 378.24 g). Based on location, minimum and maximum carapace width was represented by mangrove crab from Manipa island whilst minimum and maximum weight were represented by mangrove crab from Wael and Manipa island, respectively. Mangrove crab in the area showed isometric growth for all locations with condition factors closed to unity. Monthly sampling showed that minimum and maximum carapace widths were found in November and March, respectively. Minimum weight was found in October to December and January, whereas maximum weight was found in March. Isometric growth of mangrove crab occurred in all sampling periods except for September (negative allometric) and November (positive allometric). Condition factors for all sampling periods closed to unity.