Published on: 01/02/75
The annual cycle of Alcyonium digitatum
The annual cycle of Alcyonium digitatum was studied in the area around the south of the Isle of Man. There is an annual cycle of feeding activity, with normal activity from January to July, but from August onwards with an increasing proportion of colonies remaining permanently contracted; by November 90% are in this condition. Activity is resumed in December and January. This cycle correlates with the cycle of gametogenesis, which takes 12 months in both sexes. It commences in December or January, continues through a full year and the gametes are spawned during the following December or January.