FECUNDITY OF THE CRAB CALLINECTES-ORNATUS ORDWAY, 1863 (DECAPODA, BRACHYURA, PORTUNIDAE) FROM THE UBATUBA REGION, SAO-PAULO, BRAZIL

The objective of the present study was to characterize the fecundity o f Callinectes ornatus from the northern coast of Sao Paulo, Brazil. To study the fecundity and its relationships to size, brood weight, and egg size, the ovigerous females were collected at 2-month intervals fo r two consecutive years (January, 1991 to November, 1992) in the Ubatu ba region using a fishing boat equipped with an otter-trawl type of ne t. After collecting, the animals were screened, bagged, labeled, and s tored frozen. Only data from 38 females carrying early stage eggs were considered. In the laboratory, the specimens were thawed at room temp erature, the pleopod structure with the egg mass was removed and the e ggs were carefully removed from the pleopods. The samples were then fi xed in 10% formalin and stored in 70% ethanol, until the time for proc essing. Processing followed the method of Hines (1982, 1988). Followin g the frequency determination of carapace width and fecundity, mean eg g number, mean volume and mean dry weight of brooded egg mass were det ermined for each class obtained. Data were analyzed by regressions of log-log transformations for allometric plots (Y = aX(b)) of reproducti ve variables versus carapace width. Carapace width was one of the main factors for the determination of fecundity, which ranged 171 570 +/- 94 634 eggs, with females of the same size class presenting a wide amp litude of variation. This supports the hypothesis that portunid female s present staggered spawning, possibly presenting more than one period of reproduction within one year. The present species showed lower fec undity than the remaining portunids studied, but they did show a rapid and efficient embryonic development, presumably capable of assuring r eproductive success.