18 



Fishery Bulletin 100(1) 



and C sapidus deviated significantly from the normal 

 Mendelian ratio. Sex ratios for C. bocourti and C. exas- 

 peratiis did not differ significantly from equality, possibly 

 because of low sampling numbers for these species. In the 

 estuarine site, none of the sex ratios deviated significantly 

 from an even proportion, although C. danae did show a 

 slight bias toward males (Table 7). 



No berried females appeared at the foreshore nor at off- 

 shore stations. Only two ovigerous females were caught 

 during our study; both were C. danae and were collected 

 at the estuarine site in March 1994 (CL (carapace length]: 

 32.4 mm), and in May 1994 (CL; 43.25 mm). 



Body size 



Table 8 shows the carapace length (mm) of the most abun- 

 dant crab species at the foreshore and estuarine stations 

 in Ensenada de La Vela. Callinectes danae from the fore- 

 shore stations were larger than those from the estuarine 

 site (?=3.799, P<0.05, df=185). The mean cephalothorax 

 length in this species from the foreshore stations was 

 29.75 mm, whereas in the estuarine zone, crabs averaged 

 25.16 mm. The average size of adult females from the 

 estuarine station did not differ significantly from those at 

 the foreshore stations. Adult males from the foreshore sta- 

 tions, however, were significantily larger than those from 

 the estuarine site. Male and females sizes did not differ 

 significantly in the foreshore stations, whereas at the estu- 

 arine site females were significantly larger (Table 8). Aver- 

 age carapace length of A. cnbrariiis (?i=216) was 20.10 

 (range: 9.48-56.55; SE: 0.496). Juvenile females were sig- 

 nificantly larger than juvenile males (<=5.02; P<0.001; 

 df=148). Body size characteristics of C. bocourti are shown 

 in Table 8. No differences in size between adult C. bocourti 

 males and females from the estuarine site were found 

 (?=0.187; P>0.5; df=14). All Kolmogorov-Smirnov tests run 

 for normality of carapace length distribution for species 

 that were compared at the foreshore and estuarine sta- 

 tions, were statistically nonsignificant. 



Discussion 



Of the nine species of Callinectes that have been reported 

 for the tropical Western Atlantic (Williams, 1984), seven 

 appeared at the foreshore of Ensenada de La Vela during 

 our study. The species with the widest distributions were C. 

 danae and C. sapiduf;. which were the only ones to appear 

 at all the stations by the sea margin. Callinectes maracai- 

 boensis and C. larvatus had the most restricted distribu- 

 tion, occurring only in the estuarine site, and C. exasperatus 

 was present only in the estuary and at one of the marine 

 stations. At the marine foreshore stations, A. crihrarius was 

 the dominant species, with a share of 78% of the total catch 

 in this ecotope, whereas C. danae (19%) was the second 

 most abundant species. Meanwhile, in the estuarine site, 

 where A. cribrarius was absent, C. danae was the prevail- 

 ing species, followed by C. bocourti. Overall, the highest 

 diversity was registered at the estuarine station, whereas 

 at the foreshore the highest diversity was recorded in the 



