Large colonies of starfish populate the rock platform of Motukiekie Beach near Greymouth on the west coast of New Zealand’s South Island.
The rugged and picturesque coastline offers spectacular views of sea stacks and cliffs intersected by flat sandy beaches. These sea stacks rise beneath a 330 ft (100 m) vertical cliff. At high tide, the waves reach the wind-bent trees growing on top of the rock spires and crash against the vertical cliff with impressive force and sound. The tidal range is about 11.5 ft (3.5 m), allowing access to this rocky platform only for a short period during low tide, which must coincide with dusk or dawn to provide the perfect low-light conditions.
Even at low tide, a few waves from the swell offshore are powerful enough to completely flood the rock platform, with water levels rising to waist height. The channels between the rock platforms almost fall dry between the waves. A long exposure therefore makes it possible to capture the sequence of a large wave as it rushes through the channels, creating a ghostly appearance before finally flooding the platform.
The area is inhabited by bright-orange starfish up to 14 inches (35 cm) in diameter, called Stichaster australis, which feed on abundant horse mussels. It is remarkable that the rocks are of almost the same age as the evolutionary lineage of the class Asteroidea to which these starfish belong. When the rock, called greywacke, was deposited as muddy sediment on a deep ocean seabed in the Ordovician, about 490 million years ago, it was also around the time when the first starfish evolved from the group of animals called Echinodermata, to which sea lilies and sea urchins also belong.
Although Stichaster australis is a modern species, it truly belongs to a lineage of living fossils that has been successful in inhabiting Earth for nearly 490 million years.
