Variations in population structure in the genus <i>Tetraclita</i> (Crustacea: Cirripedia) between temperate and tropical populations. I. Fecundity, recruitment, mortality and growth in <i>T. rubescens</i>

Abstract

Studies in a population of Tetraclita rubescens in Ellwood and Arroyo Hondo, California indicate that individuals of this species reach sexual maturity at the end of the second year of life but reproduction occurs in the third year. Recruitment seems to be lower, when compared with other barnacle species. The results suggest that successful recruitment occurs every two years.

As expected, the mortality is extremely high in the Zero and one year old classes. Predation appears to be important as a factor controlling differential mortality rates.

When the two study sites are compared no significant differences are found on the growth rate of barnacles. The younger age classes exhibit a period of rapid growth during the winter and early spring. Growth then tends to be fairly constant.