Brooding Anemone (
Epiactis prolifera) is found in the eastern North Pacific Ocean, from California north to Alaska, where it occurs on rocks in the sublittoral zone in areas exposed to wave action (
Fautin 2010,
Wikipedia 2011). In BC, it is found along the coast. It grows to three cm in height and five cm in diameter; colour is variable and individuals may be brown, pink, red, or green (Wikipedia 2011). It is one of 4 B.C. species in this genus.
This species is interesting in that, unlike most other sea anemones that have separate sexes, it is hermaphroditic. Thus, an adult produces both sperm and eggs, and self-fertilisation is common. An individual actually begins life as a female, then later becomes hermaphroditic. To add to the complexity, if it reproduces at a younger age when it is female, it usually reproduces parthenogenetically, that is, without the need for its eggs to be fertilised. In such a case, all the offspring are female. The eggs are produced in, and released from (whether fertilised or not), the mesenteries within the digestive cavity. They emerge from the mouth and tumble down the parent's body where they lodge in special folds of the skin and grow to juvenile size. The juveniles are motile from a small size and readily crawl off of, and back onto, the parent anemone. At about 3mo of age, the youngsters leave the parent permanently and take up solitary life.
For more on reproduction in the Brooding Anemone, go to A SNAIL'S ODYSSEY and scroll down to the section titled "Epiactis prolifera".
Note Author: Tom Carefoot, Department of Zoology, University of British Columbia.