Influência da zonação sobre a estrutura populacional e biologia reprodutiva de UCA Leptodactylus (Crustacea : Decapoda : Ocypodidae) em estuários do Estado de Sergipe

The present study investigated the effect of different strata of tide on the abundance, size, sex ratio, population structure, relative growth, morphological sexual maturity, amount of ovigerous females and reproductive burrows in U. leptodactylus. To this end, monthly collections were made from January to December 2013 in two strata of the intertidal, estuaries of Sergipe river and Vaza-barris river, using a square with internal area of 90cm², launched ten times randomly within each strata. For each stratum monthly measures air temperature, substrate temperature, water temperature, salinity and samples episubstrate for the determination of particle size and composition of organic matter were taken. In the laboratory, crabs were sexed, measured and preserved in 70% alcohol. The monthly results were statistically compared between strata and estuaries, there are similarities in environmental factors analyzed between strata, with an analysis of the abundance, size, relative growth and sexual maturity divergent between the same strata.The abundance and size of crabs were higher in the open strata of both estuaries, with the estuary of Vaza-barris river more abundant than estuary of Sergipe river, which in turn showed higher crabs. The sex ratio was not significantly different between the strata of the estuary of Vaza-barris river, but presented to the estuary of Sergipe river, where in the open strata occurred more males and more females in the vegetated strata. Population structure showed 19 classes of size 0.5 mm with modal distribution of recent juveniles for vegetated strata and adults to open strata. Juvenile and adult crabs showed positive allometric growth between carapace width and length of the propodus and width of the abdomen, separately for each sex. The fiddler crabs vegetated strata matured in smaller sizes than that observed for the open strata in both estuaries, in the estuary of Vaza-barris river males and females matured with 6.18 and 5.26 mm and 4.94 and 4.91 mm carapace width in open and ...