Abstract
The occurrence of adults and copepodid stages III-V of Chiridius armatus ( = Aetideopsis armata) in a water column in Korsfjorden was recorded with samples taken approximately every second week during a three-year period. This species breeds biannually in the fjord and has no consistent seasonal differences in development rate. The maturation time from stage III usually varies from two weeks to four months and the time between peaks of adult females (the population renewal time) is from four to eight months.
Prosome lengths measured in five consecutive generations were greater for stages IV-VI in spring-summer generations than in autumn-winter generations. Adult females were heaviest in the summer and lightest in the winter and their caloric values (cal/mg) were least in the spring. The caloric values for stage V copepodids, combined over three months, were significantly higher than those for adult females during the same time period. The dry weights of both males and females at stages V and VI were directly related to their prosome lengths in spring 1974.
In the three years of observation, the estimated biomass of the standing stock of adult females in the 690 m3 water column usually varied between 25 and 100 mg dry weight. The estimated energy content of this stock was generally 150 to 500 calories.