Bedrock and boulder

Bedrock, boulders and rubble surround Cook Island and extend from the shallowest parts of the aquatic reserve to depths greater than 12 metres in some areas.

Marine life

Bedrock, boulders and rubble provide an essential habitat within Cook Island Aquatic Reserve, where algae, hard and soft corals, anemones, sponges, shellfish, sea squirts, barnacles and a multitude of other sea creatures can grow and live. Their presence attracts many other creatures to the rocky reef to feed, like urchins grazing on algae or green moon wrasse picking small invertebrates from the rocks.

Mobile marine life including fish, feather stars, sea stars, urchins, crabs and painted crays inhabit the bedrock and boulder habitat. The overhangs, crevices and hollows created by the network of boulders offer refuge to nocturnal species like the honeycomb eel, a safe place to hide for many cryptic reef species like pencil urchins, and a place to rest for green turtles and starry puffers.

Common cleaner wrasse establish cleaning stations at strategic spots around the reef, with a nearby shelter in the reef so they can retreat to safety. Female leopard sharks and grey carpet sharks lay their eggs among the rocky reef.