Reproductive ecology of the intertidal sea anemones Anthopleura xanthogrammica (Brandt) and A. elegantissima (Brandt): Body size,habitat, and sexual reproduction

Anthopleura xanthogrammica (Brandt) and A. elegantissima (Brandt) were collected monthly (1974–1976) from a variety of intertidal habitats in Washington State. Histological preparations were used to examine oocyte maturation, testis maturation, gonad number, and gonad volume. Maturation was examined over two years and both species were found to build gonad during the winter, spring, and summer followed by spawning in the late summer and autumn. Gonad volume and gonad number increase with individual size after a certain minimum size has been reached. Gonad volume as a function of body size does not change with habitat although the size structure of the population may change substantially.