840ha at south eastern end of Mercury Bay. Semi-exposed coast typical of the Coromandel Peninsula. Kelp forest, urchin barrens, sand flats and warm temperate reef fish. Article of interest: From reserve to reserve


These islands have been a protected pest free environment since 1933 with tuataras and bird life such as storm petrels. A permit is required to land. The water clarity is 15 to 30 metres much of the year and water temperatures reach a pleasant 22 degrees Celcius in summer. Some of the dive sites here include:

The Sugerloaf

– drop offs attract great fish life and the Pins at 12m is well worth a look. MacGregors breaks at 30m+ with several pins tightly grouped.

The Rambles at Ugly Point

– fabulous at 21m with up to 12m rock formations above you. The Jungle and the Dromedary are huge hunting/ rambling grounds.

The Sieve

(Elephant Bay) and the

Flat Island

caves both need the sun to be in the right place for maximum enjoyment.

Len’s Reef

is a major feeding station starting 8m below the surface and dropping to 70m+.


NW corner of flat island, aldermen islands. Depth:5-15m. Nice dive for all levels of divers. Cave system with three entry and exit points. Very safe as you can surface anywhere on the dive. Best entry point is from the north, swim south to the main cave which has a variety of exits. Schools of demoiselles, blue maomao plus snapper, wrasses and black angels. Occasional crayfish and yellow moray eels in the cracks along with schools of big eye. The aldermen sialdns are a nature reserve so no landing is permitted.

Stingray Rock

Typical pinnacle with steep walls covered with sponges, hydroids and ascidians. Large schools of pink maomao, demoiselles, butterfly perch and trevally. Some current so stay close to the walls. Red moki and leatehrjackets feed on the encrusing life and the occasional kingfish, shark or marlin may come past. There is usually a large stingray population around the pinnacle. Awesome dive in blue water.

Mooring Bay

Nice protected site with good snorkelling. Several swim throughs in the bay which opens onto the edge of Shark Alley. Plenty of reef fish and pelagics in summer. Some large yellow morays in the cracks and often there are stingrays and eagle rays resting on the bottom. The Sandager’s wrasses are very friendly here.

Nudibranch Wall

One of those dives for the macro photographer. There’s usually several species of nudibranch here with Jasons and apricot varieties the most spectacular. The wall is a mass of colourful invertebrate life so you have to look hard to find the smaller nudis. The usual school and reef fish cruise around behind you, if you have time to turn and look.

Orca Bay

Really nice bay with good shelter from north and west winds. Great kelp gardens with reef fish amongst them and school fish over them. Both moray and conger eels in the cracks and crevices. There are some nice swim throughs on the northen side and crayfish usually become more common as you go deeper. Nice sponges and other invertebrates below 15m.


The best dive spots are King Rock and the points on the outside of the islands. The broken up wreck of the Manaia lies off Slipper Island. Other popular diving spots are the Watchman, Penguin and Rabbit Islands, and 30 metre + dives around Rat Rock and the reefs.


An easy dive in shallow water. There are still numerous identifiable bits of the ship including shaft and some plates. Often small crayfish amongst the boulders and school of fish over the top. Some of the fish are used to divers and will hang around hoping for a handout. Well worth a visit if you have never seen the wreckage of a ship underwater.

Rat Rock

This exposed dive site often has current. The walls are covered with jewel and common anemones and red moki hide in the cracks along with crayfish and yellow moray eels. Schools of butterfly perch and demoiselles feed in the current. Banded and scarlet wrasses move amongst the kelp-covered rocks along with leatherjackets. The cracks hide some unusual sea shells, like circular saw, trumpet and helmet shells.


Unique island diving experience with 5 fully self-contained chalets, only 20 minute boat ride from Tairua

Phone: +64 7 864 7560



Nearest boat launching at Whitianga. This area has some of the most varied underwater terrain in New Zealand with reefs, sandy bottoms, pinnacles, caves, drop-offs and islands. There is always an opportunity for a great dive in this area, providing there hasn’t been a recent storm.

Never Fail Reef

1 km off northen end tip of Great Mercury Island. 0-33m deep. Best dived when winds are form the southwest. There is usually some current. The rock wall is steep and covered with kelp to 20m. Hydroids, ascidians and sponges cover the rocks below 12m. Several large caves may have big red crayfish and less often packhorse crayfish. Common fish are red moki, butterfish, John dory, scarlet and banded wrasses. Big schools of baitfish and kingfish in summer.

Coralie Bay

East side, Great Mercury Island. 0-25m in depth. Good place to anchor, snorkel/dive. Plenty of kelp covered rocks and good fish schools, especially in summer. Usually a few crayfish in the deep cracks along with large yellow moray eels. John dory are often seen over the kelp forests and there are good numbers of reef fish. Below 12 metres is untold colourful invertebrate life.

Red Mercury Island

Easternmost island in the mercuries. 0-40m in depth. Again the wind and swell control diving here. On its day is an amazing dive with huge kingfish and masses of smaller school fish. Crayfish in the reefs under the kelp and also in deeper holes in the sponge gardens. Giant boarfish haev been seen at the edge of the deeper reefs and sunfish are regularly seen in summer. Plenty of macro life on the walls for photographers.


Hahei is a small settlement near Cathedral Cove on the eastern side of the Coromandel Peninsula, in the beautiful Coromandel region.

Hahei, Coromandel, New Zealand, offers a top selection of diving attractions for those who enjoy the great outdoors and fascinating underwater life.

Motueka(Pigeon) Island

Location: North of Hahei, 2km offshore. Depth: 0-20m. Lots of reef fish and very colourful walls on teh seaward side. The fish numbers make the benefits of the marine reserve obvious, especially the large snapper. Large crayfish in the deep fissures and canyons too. Apricot and Jason nudibranchs can be very common seasonally. Marblefish are often seen around this area and there’s a yellow moray in almost every hole.

Gemstone Bay

Location: 15 min walk from the carpark above Cathedral Cove. Depth: 0-8m. A great family snorkel site but you need a boat or kayak for scuba. Huge crays amongst the rocks, sometimes in less than three metres. Snapper and red moki much more common than outside the marine reserve and plenty of small reef fish. The Dept of Conservation information floats on the snorkel trail help identify the fish, seaweeds and invertebrates.

Kingfish Rock

Location: Between Mahurangi and Motueka islands. Depth: 5-23m. This pinnacle, inside the marine reserve, abounds with fish. You’ll see snapper, two-spot demoiselles, leatherjackets, spotties, marblefish and much more. The rocks are covered with colourful anemones, hydroids and sponges. In summer kingfish hunt through the schools. There’s often a large school of leatehrjackets feeding on the shallow invertebrate life.

South Sunk Rock

Location: North of Mahurangi island. Depth: 0-30m. This rock is jsut outside the marine reserve and benefits from it being surrounded by fish. The reeftop has large green-lipped mussels, but regulations forbid you taking them while in possession of scuba gear. Good kelp growth and yellow moray eels peer out from cracks. Big kingfish in summer amongst the prolific baitfish schools.

Mahurangi (Goat) Island

Location: Just off Hahei beach. Depth: 0-25m. Part of the northen end is in the marine reserve. Numerous dive sites around the island with Spectacle Reef on the eastern side, outside the marine reserve, among the best. Lots of deep canyons with apricot and Jason nudibranchs. Schools of maomao, demoiselles and butterfly perch. Some crayfish in the deeper cracks. Kingfish and the baitfish schools they feed on are common in summer. Fur seals can be seen in winter.


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