ABSTRACT
A two-year study of the size frequency of an offshore population of the sea biscuit Clypeaster ravenelii in the northern Gulf of Mexico indicated a generally static population structure. Little evidence of significant recruitment occurred, suggesting that small numbers of juveniles enter the population annually and, should they occur, larger recruitment events appear to be episodic. Using an indirect measure of growth (temporal comparisons of population size frequency) it was estimated that adults (> 9 cm long diameter) grow very slowly, with an increase in test length of 0.32 cm per year.
