LABORATORY BEHAVIOR OF ADOLESCENT AND ADULT MALES OF THE SNOW CRAB (CHIONOECETES-OPILIO) (BRACHYURA, MAJIDAE) MATED NONCOMPETITIVELY AND COMPETITIVELY WITH PRIMIPAROUS FEMALES
B. Saintemarie et al., LABORATORY BEHAVIOR OF ADOLESCENT AND ADULT MALES OF THE SNOW CRAB (CHIONOECETES-OPILIO) (BRACHYURA, MAJIDAE) MATED NONCOMPETITIVELY AND COMPETITIVELY WITH PRIMIPAROUS FEMALES, Canadian journal of fisheries and aquatic sciences, 54(2), 1997, pp. 239-248
In the laboratory, virgin females of snow crab (Chionoecetes opilio) w
ere placed singly with one or two males to investigate mating behavior
. Physiologically mature males, both adolescent (i.e., chelae undiffer
entiated) and adult (i.e., chelae differentiated), mated with females.
Typically, matings comprised a precopulatory period, one or more copu
lations, and a postcopulatory period during which the female extruded
eggs. Some females copulated after oviposition. In noncompetitive mati
ng, adult males of 40-60 mm carapace width had repeated but brief copu
lations, while adult males of 120-140 mm carapace width had one long c
opulation. In pairs of competing adult males, large body size was an a
dvantage both in taking over a female from a rival and in preventing f
emale takeover by a rival. However, in competitions between an adult m
ale and a larger adolescent male, the adult was more likely to disposs
ess his rival or prevent takeover. The variance in mass of ejaculate s
tored by females was explained (98%) by total copulatory time and numb
er of copulations. Females with two mates obtained more copulations an
d larger ejaculate stores than females with one mate, suggesting that
interannual variability in ejaculate stores reported for wild females
is related to the level of male sexual competition.