ABSTRACT
Population dynamics, growth and life-span of the comatulid crinoid Antedon bifida (Echinodermata). Antedon bifida is an annual species. Individuals reproduce in the Spring following their year of birth, and most of them (85%) die in the course of the 6 months after reproduction. A. bifida grows continuously with a growth rate of 3,3 mm per month (arm length) and a pinnule production rate of 0.2 pinnule per day. The mean arm length of one-year old individuals is 40 mm (male) and 34 mm (female), and the mean number of pinnules per arm is 70 (male) and 60 (female) (with the 30 most proximal pinnules being genital). One-year old premature males have longer and lighter arms than one-year old premature females. Such differences presumably correspond to a difference in reproductive effort in individuals of both sexes.
