Interannual variability of sperm reserves and fecundity of primiparous females of the snow crab ( Chionoecetes opilio ) in relation to sex ratio

• Published in: Canadian Journal of Fisheries and Aquatic Sciences
• Main Authors: Sainte-Marie, Bernard, Sévigny, Jean-Marie, Carpentier, Mireille
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 2002
• Subjects: Aquatic Science; Ecology, Evolution, Behavior and Systematics; Chionoecetes opilio; Snow crab
• Online Access: http://dx.doi.org/10.1139/f02-162; http://www.nrcresearchpress.com/doi/pdf/10.1139/f02-162

Demographics of adults and reproductive condition of primiparous (first brood) females of the snow crab (Chionoecetes opilio) were monitored annually from 1994 to 2002 at a fished site to investigate the possibility that sperm supply limits embryo production. Abundance of primipara fluctuated 533-fold because of a recruitment pulse, and this caused a large oscillation in the sex ratio of adult males to primipara. Annual mean of stored ejaculate weight (SL) and potential fecundity index (PF, clutch weight × percent fertilized eggs) adjusted to constant primipara carapace width ranged from 31 to 130 mg by spermatheca and from 1.97 to 3.43 g by clutch, respectively. Annual mean of SL and number of stored sperm (range 3.81 × 10 6 to 35.00 × 10 6 sperm by spermatheca) decreased when sex ratio decreased, probably because of a combined reduction of sperm allocation and female promiscuity. Annual mean PF was negatively correlated with abundance of small males, which may reflect egg losses during postoviposition matings. Although sociosexual context has a large impact on reproductive condition of primipara, the possibility that sperm supply limits embryo production could not be confirmed or excluded because of the complexity of snow crab mating behavior.