Common Brittlestar

Photo: von36 · CC BY-NC

Common brittlestars at Cathedral Rock reach densities of hundreds per square metre on horizontal ledges and the arch floor, creating a living carpet of writhing arms. They are suspension feeders that orient their arms toward the current to capture suspended food particles, and when current is running the entire seabed appears to be in constant undulating motion. They are a keystone species in this community, providing food for diving birds, wrasse, and starfish.