Distribution, Population and Reproductive Biology of the Fiddler Crab Uca sindensis (Crustacea: Ocypodidae) in a Subtropical Mangrove of Pohl Area

Distribution, population and reproductive biology of Uca sindensis were studied in a subtropical mangrove of Pohl port in the northern Persian Gulf. Sex ratio, distribution, population structure, handedness (evenness), diameter burrow, breeding season and fecundity were investigated. Ten 0.5 m 2 quadrates were randomly sampled during low tide periods from October 2009 to September 2010.A total of 711 crabs, 344 (47.7%) males and 367(52.3%) females, were sampled. The CW of males ranged from 4 to16 mm and of females from 5 to 17 mm indicating sexual dimorphism. The overall sex ratio was 1:0.93 and did not differ significantly from the expected 1:1 (χ test, P>0.05), however the monthly sex ratio was different from expected 1:1(χ test, P<0.05). Results indicated that the size frequency distributions of this species could also be determined through direct analysis of burrow openings (r 2 =0.99). Breeding took place during warm season of April 2009 to September 2010. Egg numbers increased with female size(r 2 =0.50). The regression analysis showed that the number of eggs increased linearly with the increase of carapace width (r 2 = 0.766, EN= 0.1125 CW-0.1129, n=31). It was concluded that two factors of temperature and TOM affected growth and reproduction pattern in U. sindensis.