Diving in New Zealand

New Zealand is made up of two main islands and a number of smaller islands. The main North and South Islands are separated by the Cook Strait, 22 km (14 mi) wide at its narrowest point.

Besides the North and South Islands, the five largest inhabited islands are Stewart Island, Chatham Island, Great Barrier Island (in the Hauraki Gulf), d'Urville Island (in the Marlborough Sounds) and Waiheke Island (about 22 km (14 mi) from central Auckland). The country's islands lie between latitudes 29° and 53°S, and longitudes 165° and 176°E.

The two main islands of New Zealand measure over 1,600 km (990 mi) long from north to south, and narrow (a maximum width of 400 km (250 mi)), with approximately 15,134 km (9,404 mi) of coastline for a land area of 268,021 km² (103,483 sq mi).

The South Island is the largest land mass of New Zealand and is divided along its length by the Southern Alps. Fiordland in the south west has steep mountains and deep fiords from the extensive ice age glaciation. The North Island is less mountainous but is more volcanically active.

The long coastline with many bays and peninsulas, and the many islands, provides a setting for a very large number of dive sites, in a wide variety of geographical environments.

New Zealand is positioned across the division between subantarctic and subtropical water masses, and this provides a large range of conditions and habitats which support a wide diversity of marine life.

New Zealand has a mild and temperate maritime climate with mean annual temperatures ranging from 10°C (50°F) in the south to 16°C (61°F) in the north.

Conditions between regions vary from extremely wet on the West Coast of the South Island to relatively dry in Central Otago and the Mackenzie basin of inland Canterbury and subtropical in Northland. Auckland, Wellington and Christchurch all receive a yearly average in excess of 2,000 hours of sunshine. The southern and south-western parts of the South Island have a cooler and cloudier climate, with around 1,400–1,600 hours; the northern and north-eastern parts of the South Island are the sunniest areas of the country and receive approximately 2,400–2,500 hours.

The weather is notoriously variable. The expression Four seasons in one day sums it up quite well.

Marine weather forecasts are available on-line from Metservice for each of the marine weather regions. These forecasts are updated daily or more frequently, and provide wind and sea state predictions from the government meteorological service. Predictions are fairly reliable for the day of announcement and the following day, and include reasonable predictions for the following three days. Gale and storm warnings, and small craft advisories are provided. The forecasts are also broadcast on VHF and can be received offshore in the relevant regions except for a few dead spots behind islands. Nowcasting services are also provided on VHF in some areas, which give continuous reports on wind at selected meteorological stations, and repeated forecasts of local conditions and tides. These forecasts are of great value for dive planning particularly for the offshore sites which require fairly long boat trips.

Several habitat types can be categorised by the physical environment. These range from soft sediment based habitats which include silts and muds in protected bays, coarse sands and gravels, pebbles and shell on exposed shorelines, biogenic reefs, formed by a variety of organisms, and rocky reefs.

The majority of dive sites in New Zealand can be dived using conventional recreational scuba equipment. Dives which are beyond ordinary recreational limits due to depth overhead or current can generally be satisfactorily handled using the appropriate equipment and skills.

Water temperatures are generally temperate to cold, and the use of drysuits is recommended for colder waters in winter or in those places where the water is not significantly warmer in summer. Water temperatures of 14°C are common in winter and spring even in the northern regions of the North Island.

Marine weather area Kaipara (North Cape to Muriwai, mostly west coast.)

• Three Kings Islands — A small group of uninhabited offshore islands to the far north of North Island.
• North Cape — The northernmost point of the mainland
• Cape Karikari

Marine weather area Brett (North Cape to Bream Head, east coast)

• Berghan Point
• Whangaroa
• Cavalli Islands
• Purerua Peninsula
• Bay of Islands
• Cape Brett
• Whangamumu
• Mimiwhangata
• Poor Knights Islands: A marine reserve around a group of small uninhabited volcanic islands 24 km off the north east coast of New Zealand, at 25°28' S, 174° 33' E.
• Tutukaka
• Hen and Chicken Islands — A group of small uninhabited islands off the east coast of Northland.
• Whangarei
• Mokohinau Islands — A group of small uninhabited islands off the east coast of Northland.
• Bream Bay

Marine weather area Colville (Bream Head to Great Mercury Island)

• Great Barrier Island — This large inhabited island is the north eastern limit of the Hauraki Gulf. Much of the diving is in the east side, and outside of the gulf.
• Little Barrier Island
• Leigh and Omaha Bay
• Tawharanui
• Kawau Bay and Island
• Rakino Island
• Whangaparaoa Peninsula
• Waiheke Island
• Auckland North Shore

Marine weather area Raglan (Muriwai to Cape Egmont)

• West Auckland

Marine weather area Colville (Bream head to Great Mercury Island)

• Coromandel West Coast
• North Coromandel
• Cuvier Island
• Whangapoua Bay
• Mercury Islands

Marine weather area Plenty (Great Mercury Island to Cape Runaway)

• Whitianga
• Hahei
• Alderman Islands
• Tairua
• Slipper Island
• Whangamata

Marine weather area Colville (Bream Head to Great Mercury Island)

• Raglan Kawhia Coast
• Lake Taupo— Inland fresh water lake.

Marine weather area Plenty (Great Mercury Island to Cape Runaway)

• Mayor Island
• Tauranga
• Motiti Island
• White Island
• Whakatane

Inland sites

• Rotorua Lakes

Marine weather area Portland (Cape Runaway to Cape Turnagain)

• Cape Runaway and East Cape
• Gisborne
• Mahia Peninsula
• Napier

Marine weather area Raglan (Muriwai to Cape Egmont)

• Sugar Loaf Islands

Marine weather area Stephens (Cape Egmont to Kapiti Island)

• Patea

Marine weather area Portland (Cape Runaway to Cape Turnagain)

• Blackhead
• Cape Turnagain

Marine weather area Castlepoint (Cape Turnaround to Cape Palliser)

• Castle Point
• Cape Palliser

Marine weather area Cook (Cape Palliser to Kapiti Island)

• Palliser Bay
• Wellington harbour
• Wellington South Coast
• Mana Island
• Kapiti Island

Horoirangi Marine Reserve, sometimes referred to as the Glenduan Marine Reserve, is to the north east of Nelson.

Marine weather area Abel (Farewell Spit to Stephens Island)

• Golden Bay
• Tasman Bay

Marine weather area Cook (Stephens Island to Cape Campbell)

• Marlborough Sounds

Marine weather area Grey (Kahurangi Point to Jackson Head)

• West Coast

Marine weather area Conway (Cape Campbell to Akaroa Head)

• Kaikoura Peninsula
• Banks Peninsula

Marine weather area Rangitata (Akaroa Head to Moeraki)

• Moeraki

Marine weather area Chalmers (Moeraki to Nugget Point)

• Otago Peninsula

Marine weather area Foveaux (Nugget Point to Long Point)

• Waipapa Point

Marine weather area Foveaux (Nugget Point to Long Point)

• Bluff
• Diving at Stewart Island

Marine weather area Puysegur (Secretary Island to Long Point and Rugged Island to Southwest Cape)

• Preservation Inlet
• Dusky Sound
• Doubtful Sound
• Milford Sound

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