These large vessels are used for installation of subsea oil extraction systems on the seabed. It was an underwater survey that scanned of seabed around Robben Island. Sea cucumbers can be ranched on the seabed. It creates a U-shaped burrow in the soft sediment of the seabed. They feed on the corals, sponges, and bryozoans that litter the seabed. They were found on the Atlantic seabed using advanced sonar scanning. Photographs were released showing the shattered remains of the submarine broken up on the seabed. Drilling is another means of sampling the seabed. The wreck lies on the seabed separated into multiple sections. A sea anchor is a drogue, not in contact with the seabed. It was made of oak piles driven into the seabed with boulders stacked between. They feature madreporic mangroves, with a rich seabed and colorful algae. Efforts continued with the hope of recovering various large pieces of wreckage from the seabed. The average depth is below the seabed. The wobbegongs tend to be ambush predators, lying hidden on the seabed until prey approaches.