Although they can be found in almost any situation, Plumose Anemones or Metridium senile, do best in high energy areas where the current and tide are at their strongest. Unlike most other anemones, these are filter feeders and their feathery tentacles act as filters, trapping plankton as the water rushes through them. The rock wall on the picture is ideal for them as it is at right angle to the tidal flow and they dominate its surface and virtually exclude other species from obtaining a foothold. When the tide is well past its peak, they will gradually retract their tentacles and collapse their bodies until the flow starts again. They exist in large groups in favourable places - see separate picture.
North Sea. St. Abbs Marine Reserve