At the Goat Island Marine Reserve divers can unload their gear near the beach before parking up the hill. From there it is a short walk across the sand and into the water. Shag Rock, about 150m directly off the beach is one of the best dive sites. Schools of silver drummer move through feeding on the kelp forest. Snapper follow divers and their bright blue spots glow in the sunlight. Rays rest on the sandy patches and piper flit around near the surface. Crayfish are hiding under the boulders, but are protected here as is all marine life.
From a boat or a kayak, divers can access dive sites further around the island or along the coast. North Reef is a large rocky area just north of the NW point of Goat Island and is best dived when there is limited swell or current. Schools of large silver drummer, blue maomao, big snapper and occasional blue moki swim around the colourful invertebrate-covered reefs.
Another marine reserve at Tawharanui, just across Omaha Bay, is best dived from a boat. There are plenty of large crayfish to see here, plus colourful sponges, ascidians and other marine invertebrates.
Even outside the marine reserves there are some exceptional dive sites like the Outpost at the Leigh Harbour entrance. It's just a short boat trip out and has a colourful wall to dive alongside. There are surprisingly large numbers of fishes alongside the wall that drops to sand.
Leigh Reef is easy to find as numerous boats anchor there to fish. Divers should be experienced and a boat person is a must as there is usually some current. In summer big kingfish feed on the schools of baitfish. There is a wealth of colourful reef dwellers and plenty of rocky reefs and caves to explore.
Matheson Bay can be accessed off the beach or by boat. There is a small island that gives some shelter and plenty of interesting invertebrate life around it. Divers won't see as many fish as in the marine reserves but may spot seastars, kina, crabs and seashells.