From April 2000 to April 2001 all individuals of C. danae Smith, 1869 included on one otter-trawl by-catch was fortnightly sampled at Shangri-lá's fish market (25°37'30"S, 48°25'08"W) in order to study their population structure and reproductive pattern. Each specimen was sexed and measured (CW = carapace width, excluding lateral spines; WW = wet weight). The gonadal maturation stage was determined macroscopically based on its color and size. The egg mass of the females was separate for fecundity analysis. Prevalence of adult females (including ovigerous ones) was observed comparing to other categories. Sexual proportion was 0.9:1 (males:females). Size at first sexual maturation was estimated at 60.5 mm for males, and 52.7 mm for females. WW/WC relationship was isometric for males and females. The carapace width of ovigerous females was between 43.2 to 79.5 mm (67 ± 8 mm), and fecundity varied from 25,127 to 246,676 eggs, with an average of 127,177 eggs per female and mean egg diameter was 0.22 mm. The highest presence of ovigerous females occurred during winter and summer.
Fecundity; population biology; seabob by-catch; Sex-ratio; swimming crab
