Where the open sea meets rugged areas of land and steep walls plunge into the water, it is often almost impossible to see the rock surface itself. This is because the tidal flow and wave action in these places are at their strongest and encrusting animals that filter feed settle here out of the plankton in the Spring in great variety. They develop rapidly as they are effectively being force fed by the wave action and turbulence. Because they are low-growing, they are able to withstand the harshest of conditions. However, many of them die off or regress in the winter as light levels and the plankton supply diminish.

Location: North Sea. St. Abbs Marine Reserve