Study of behavior of two species of fiddler crabs, genus (Ucasindensis and Ucaannulipes) in the tidal flat of Rig port in Bushehr

Fiddler crabs typically live in the tidal muddy and sandy flats. According to the tides play a major role in the distribution of species, this study was conducted in the tidal flat of Rig port in Bushehr in sumer 1391. The more common Ucaannulipes lives in sandy while Ucasindensis lives in muddy areas with sandier sediment. There are differences between the sexes of these two species in field observations. They are also quite different patterns of behavior. However, to compensate for a male crab claws for power supply need to spend more time than the females.The male crabs to be produced larger mud pellets than females.Male fiddler crabs use the major claw to perform a waving display as a form of female courtship.Male fiddler crabs could increase food ingestion by having faster feedingmotions, by feeding for a longer period of time than females, by feeding on largermouthfuls or by having a higher assimilation efficiency of the food they do ingest. Distribution of the Ucasindensis significant increases in very fine grained sand and coarse silt, as well as distribution of the Ucaannulipes considerable increases in very fine silt and coarse clay. Statistical software SPSS was used for data analysis. The aggressive behavior in males can be seen, the behavior of most of the species Ucaannulipes is Ucasindensis.