Coral heads and coral gardens dominate the bottom of Challanger Bay. At 12 m the substrate is covered with an colorful mosaic of hard and soft corals. Macro life is superb-a stunning variety of nudibranchs, cuttlefish, flatworms, clams, feather stars, sea stars and anemones, sap suckers, molluscs, crabs and shrimps are regulary found on and around the corals. Masses of batfish, angelfish, sweetlip, gobies, damsels, wrasse, pipefish, pufferfish, filefish, rock cod and hawkfish reside around or on the reef. Look out for stingrays and large colonies of garden eels on the sandy bottom.