Common Cuttlefish

Photo: Jenny Morris · © all rights reserved

Skomer hosts one of the UK's most reliable cuttlefish breeding aggregations from late April through June, with dozens of individuals gathering in shallow rocky gullies to mate and lay eggs in branching hydroid colonies. Males engage in spectacular chromatic display battles — rippling waves of colour across their mantles — to impress females and intimidate rivals. After spawning, the adults die and the reef is briefly carpeted in white egg clusters, each containing a developing cuttlefish visible through the translucent casing.