Melanesia occupies a wide swathe of the southwestern Pacific Ocean, stretching from New Guinea in the west to Fiji in the east. This is a region dominated by high islands, with considerable ongoing volcanic activity in the west. A broad range of reef types fare found, although atolls are generally not as widespread as the extensive fringing and barrier systems associated with the high islands. Overall this region includes a vast area of reefs, making up about fourteen percent of the global total.

Biodiversity is high right across Melanesia, though there is diminishing diversity towards the east. The reefs of New Caledonia are best studied, and a number of reefs in Fiji have also received some scientific attention. Even in these countries, however, there are vast areas which remain unvisited and undescribed by scientists.

Papua New Guinea is one of the world's major coral reef nations, with a vast area of reefs. The total area is more than13,840 square kilometers. Lying on the eastern edge of the great center of coral reef biodiversity in Southeast Asia, there is every indication that this country enjoys remarkably high levels of biodiversity. It has suffered very little in the terms of human impacts and there are great opportunities for continued sustainable management and conservation of its coral reef resources.  The country has a vast area of coral reefs, including fringing, barrier and atoll formations.

The north coast on the mainland, particularly in the west, is little known, however there are fringing reefs in many areas, including around the nearshore chain of the Schouten Islands. East of the Sepik and Ramu river mouths fringing reefs continue, often in long unbroken stretches up to the easternmost point of East Cape, while in places barrier reefs run further offshore, notably around Madang where there are about fifty associated offshore islands.  It has been estimated that, in all, over half of this coastline may have fringing reefs. Along the southern coast, reef development is somewhat restricted in the area of the Fly River Delta and the smaller river deltas to the east, where there are extensive mangrove forests and the turbidity is high and salinities are variable. Further east, coral reefs are widespread from Port Moresby eastwards. These are sometimes termed the Papuan Barrier Reef as they run some distance offshore, separated by a lagoon about five kilometers wide. The total length of the reef is 560 kilometers, though this is broken by a number of channels.

To the north of the mainland, the westernmost islands of the Bismarck chain include a number of coralline islands surrounded by fringing reefs, and also a number of atolls, including the large Niigo Atoll, Liot, Heina and Kaniet (Sae) Islands. Reefs are also widespread, including fringing and platform structures, on the other islands north of the mainland. Perhaps the most extensive reef systems in the country however, are found in the southeast near the Milne Bay Province. The continental shelf is broad and scattered with numerous platform reefs, some with their associated islands between the mainland and the Trobriand Islands to the north. These islands are relatively flat limestone structures. East of the Trobriands are several islands and reefs, including Egum Atoll, the large Muyua (Woodlark) Island with associated fringe and near-barrier reef systems, and Budibudi Atoll in the far east. A long chain of reefs and islands extends southwest from the tip of New Guinea and here there is a vast complex of reefs. The most significant of these is the Calvados Barrier Reef, extending as a long arm along the southern edge of the continental shelf, right around the tip of Sudest Island, a total distance of some 640 kilometers. In addition to the reefs already described, quite a large number of other systems lie even more remote from the high islands.

The reefs of Papua New Guinea are only just being explored in terms of their biodiversity, and studies in the late 1990's revealed extremely diverse communities, including many hitherto undescribed species. There are over 1000 fish and 420 coral species found in this region alone. While there are affinities with the Great Barrier Reef and Coral Sea faunas, the reefs of Milne Bay and by implication all the reefs to the north are thus still closely linked to the Indonesian and Philippine centers of diversity and endemism.

The widespread use of coral reefs in Papua New Guinea is for subsistence fisheries. The dominant offshore fishery is tuna, largely conducted by foreign vessels under license. Inshore commercial fisheries include lobster, sea cucumber, trochus, green snail, pearl shell and some reef fish. The live fish trade has been operating in a few areas since 1991, and numbers of large reef fish are reported to be reduced in the northwest. There have also been reports of blast fishing, particularly around urban centers.

Direct pollution from human settlements is limited to areas close to major towns. Unfortunately there are various other threats which may significantly impact the reefs of Papua New Guinea in the near future. The major commercial industries are logging and mining. Logging is occurring over large areas, although not on the same scale as in much of Southeast Asia, and there is considerable threat that increased sedimentation will impact nearby nearshore reefs.

Mining, notably for copper, gold and silver, is a major industry, and in the late 1990's environmental controls were still weak. Deliberate or accidental discharge of mine tailings into rivers or directly offshore has caused problems in a number of locations, both by smothering corals and from toxic impacts.

A number of protected areas covering coral reefs have been declared, but the majority of these are simply marine extensions of terrestrial sites, with little or no real provisions for marine protection.

OFFICIAL, SCIENTIFIC & GOVERNMENTAL SITES:
Jane's Oceania -Papua New Guinea
Papua New Guinea Business and Tourism
The Nature Conservancy article on Kimbe Bay, Papua New Guinea

COMMERCIAL:
DiveFishSnow Travel: Papua New Guinea
Diversion Dive Travel: Papua New Guinea
GoNomad: Papua New Guinea
Wikitravel: Papua New Guinea

The Solomon Islands consist of over 900 islands widely distributed in the Western Pacific. The bulk of the land area comprises seven large volcanic islands which form a double chain running from northwest to southeast and converging on the island of Makira (San Cristobal). These islands are on the western margin of the Pacific plate and all are of volcanic origin. There is still volcanic activity in a number of locations, notably on Tinakula in the Santa Cruz Islands and on the submarine volcano of Kavachi, south of New Georgia.

Coral reefs are widespread throughout the country. A number of atolls are present, and fringing reefs are numerous around most of the islands. Barrier reefs are less developed, although there are barrier complexes with associated islands around New Georgia and northeast Choiseul and around Utupua.

Very little is currently known about biodiversity on the reefs of the Solomon Islands, however given their location and the relatively low levels of human impact in many areas, they are likely to include highly diverse and important reef structures. Additionally the coral reefs here include wide areas still largely unimpacted by human activities, although there are also areas where such pressures are large and growing. The islands have one of the fastest growth rates in the world, and 86 percent of the people are rural. Dependence on coral reefs for protein remains high and subsistence fishing is widespread. In the more populous areas this is leading to over fishing and in certain parts, such as the Lau Lagoon off north Malaita, many of the preferred edible species have been lost. Fishing methods can also be destructive, whether trampling and damaging the reefs, or poison fishing including traditional methods that use coastal plant species to provide the poison. This poison is unselective, killing a number of non-targeted species and reportedly damaging corals.

Commercial fishing has probably had more far reaching effects across the islands, notably for selected target species. Both trochus and sea cucumbers are already overfished and their numbers are declining rapidly in many areas. A significant giant clam fishery peaked in 1983,but overharvesting has depleted these stocks in all areas, exacerbated by illegal poaching by foreign vessels.

One unusual but highly significant threat to reefs in the Solomon Islands comes from the use of lime in the habit of chewing betel nuts. The latter are taken from the fruits of a palm and are chewed with a pepper leaf and lime in an addictive habit. The lime is prepared by burning branching corals, and major users may consume 20 kilos of lime year (derived from over 30 kilos of live coral), and in some areas, such as the lagoon reefs of Malaita, these corals are highly depleted. One estimate suggested that about 6 million kilos of lime are used per year, derived from 10 million kilos of live coral, making this one of the largest single threats to reefs in the country. Other  threats to the Solomon Island's coral reefs are sedimentation from increased logging, and  raw sewage pollution from population centers.

OFFICIAL, SCIENTIFIC & GOVERNMENTAL SITES:
Jane's Oceania: Solomon Islands
U.S. Government Website: Solomon Islands

COMMERCIAL:
Undercurrent: Scuba Diving in the Solomon Islands


The Archipelago of New Caledonia is dominated by the large land mass of Grande Terre, the third largest island in the Pacific (after New Guinea and New Zealand). It is of continental origin, having diverged from Australia some 65 million years ago, and has a mountainous interior rising to more than 1,600 meters. The shallow shelf on which the island sits extends a considerable distance to the northwest, and includes the continental Iles Belep and a number of smaller islands and coral cays further north. The shallow platform on which these islands lie is rimmed by the world's second largest barrier reef, over 1,300 meters in length. There are quite regular passes in the reef, associated with river mouths on the mainland. In a few locations to the north, notably along the Grand Recif de Koumac and the Recif des Francais, a deep lagoon has developed with the single structure of the outer barrier reef, forming a rare double barrier structure. Between the barrier reef and the mainland there are many platform structures, while fringing reefs are also widespread in many areas.. To the northwest the barrier reef continues beyond the Iles Belep up to a channel, the Grand Passage. beyond this there is a group of reefs known as the D'Enrecasteaux Reefs, including Huon Atoll, Surprise Atoll and a number of smaller atoll and barrier-like structures.

Due east of Grande Terre is the low-lying chain of the Loyalty Islands. Mare in the south has some volcanic rocks, while the others are composed primarily of uplifted limestone. Fringing reefs encircle most of Mare and Lifou. Ouvea to the north is a partially uplifted and tilted atoll with fringing reefs along its eastern coastline, but with a wide reef-fringed lagoon to the west. Moving northwest is the small atoll of Beautemps-Beaupre and then a small group of reefs known as the Astrolabe Reefs. Lying in considerable isolation to the northwest of the Loyalty Islands and to the east of the D'Entrecasteaux Reefs is another significant reef structure, the Petrie Reef. Far to the east of the Loyalty Islands are the two small islands of Matthew and Hunter.

Over 550 kilometers west of Grande Terre are two very large shallow reef areas. the Chesterfield Islands are coral cays along the perimeter of a large atoll. A shallow reef with a very steep outer slope marks its northern and western margins, while to the southeast there is no clear atoll margin, but a gentle slope to considerable depths. To the south, Bellona Atoll again has a number of shallow reefs and a few coral islands, notably along its western perimeter.

The location of New Caledonia relatively close to the global center of coral diversity, combined with the large area and variety of reefs, insures very high diversity. Unlike many other reefs in the region these have been the subject of considerable study, although many areas in this large archipelago nonetheless remain poorly known and undescribed. Thus far about 1,950 fish species have been recorded, about 5,500 mollusks, 5,000 crustaceans, 600 sponges and 300 corals. About 5 percent of the species are thought to be endemic.

There is some impact on nearshore reefs in New Caledonia from sedimentation from the island's major nickel mining industry. Aside from this most of the human pressures on the coral reefs are centered around the main town of Noumea where there are localized problems of domestic pollution and some overfishing. There is a good network of marine protected areas around the southeast of the region, and there are plans to develop a similar network in the north. In addition to these, customary reserves and traditional fishing areas are recognized.

OFFICIAL, SCIENTIFIC & GOVERNMENTAL SITES:
Corp Watch: Protect New Caledonia Forest, Reef and Indigenous Rights
Environmental Defense: Article on New Caledonia's reefs and threats.
Global Response: article on New Caledonia's reefs
The Coral Reef Alliance: You can help New Caledonia's reefs.

Vanuatu represents the main bulk of an island chain which continues into the Santa Cruz Islands of the eastern Solomon Islands. Reef development is generally restricted  in the easternmost islands and greatest in the western islands. Fringing reefs predominate, though Cook Reef, north of Efate, is a small atoll like structure with no associated islands. Fringing reefs also encircle most of the islands from Efate southwards. In the central islands fringing reefs are generally not continuous and reef flats can be quite narrow. Typically reefs are best developed on eastern and northern coasts. The eastern coasts of Santo and Malakula both have wide fringing reefs and a number of coral islands on their coastlines.

The most recent survey, although likely not complete, lists 469 fish species and 295 scleractinian corals for the reefs of Vanuatu. The islands have a growing population and over 70 percent of the population relies on their traditional lands and subsistence from the ocean and land. Catch methods include gill netting, capture by hand or spear gun, and in more remote areas, traditional techniques include bow and arrows, spears, traps and traditional poisons.

Close to the urban centers there is considerable concern about pollution arising from sewage inputs, sediments and storm-water runoff, notably around Port Vila and the airport.  Away from these areas concern has been expressed about the over harvesting of some non-motile reef species. Formal protection of reef resources is not widespread, though a number of reserves have been established off Santo. For the most part however, these are not respected , or even known about, by local people.

OFFICIAL, SCIENTIFIC & GOVERNMENTAL SITES:
Innovations Report: Vanuatu -the coral reef, a record of a 23,000 year history

COMMERCIAL:
Scuba Diving in Vanuatu
Undercurrent: Scuba Diving in Vanuatu

Fiji is a vast archipelago centered on two relatively shallow geological features, the Fiji Platform and the Lau Ridge. The two largest islands of Viti Levu and Vanua Levu, together with quite a number of smaller ones, lie on the relatively shallow Fiji Platform. Fringing reefs surround most of Viti Levu, with the largest continuous fringing reef running for 100 kilometers along the Coral Coast on its southern shore. Offshore from eastern Levu the Suva Barrier Reef follows the shelf edge up to the island of Ovalua. The northern coast of Viti Levu is dominated by a very complex array of platform reef structures and intervening channels. Running northeast at some distance west of Viti Levu is a string of high islands known as the Yasawa group, again with an associated complex of fringing and patch reefs. These islands lie close to the edge of the Fiji Platform, and part of the shelf-edge is capped with Ethel Reef, a 30 kilometer barrier reef. Immediately south of Viti Levu is the island of Beqa, enclosed to the south and the west by the Beqa Barrier Reef. Further south, the large island of Kadavu is separated from the Fiji Platform by the Kadavu Passage. This island has fringing reefs along much of its coastline, but is further dominated by a 95 kilometer long barrier reef running along its southern and eastern coasts and extending into the Great Astrolabe and North Astrolabe Reefs.

The line of the Yasawa group in the west is continued eastwards towards Vanua Levu by Fiji's longest barrier reef structure, the Great Sea Reef which runs along the self edge in a near continuous chain for some 200 kilometers, gradually converging towards the coastline of Vanua Levu at its northeastern tip. The Vata Ira Channel between the two high islands is a tongue of deeper water, also fringed by elongated barrier reef structures including the Vanua Levu Barrier Reef along the eastern edge of the channel and up to the southern shore of Vanua Levu. Much of the southern shores of Vanua Levu are lined by fringing reefs, while the northern edge is marked by a similar complex of platform reefs to that of Viti Levu. Out to the east lies a complex of islands and reefs collectively called the Ringgold Islands. These include several atolls, also Budd Reef which is a near-atoll, with a group of high islets located in its lagoon. A group of reefs on the outer edge of the Ringgold Islands make up the Nukusemanu and Heemskercq Reefs, parts of which are submerged, but may be considered a near-atoll or barrier-type structure.

The Lau Islands make up the eastern edge of the Fiji group and lie at the top of the Lau Ridge, separated from the Fiji Platform by the Nanuku Channel. Most of the northern islands are high and of volcanic origin, but further south carbonate islands predominate. There are a number of atolls and near-atolls throughout the chain. The Exploring Isles make up one of the largest structures in this group, including the high island of Vanua Balavu, as well as a long barrier reef running out to the east and enclosing a number of smaller islands. Towards the center of the group the Bukatatanoa Reefs are another massive barrier reef complex. Lying considerably to the south of the main group of Lau Islands are the smaller islands of Vatoa and the atoll of Vuata Vatoa. Further south again is a complex of four small reef systems, including Oni-i-Lau, a small group of islands enclosed by a barrier reef.

The Koro Sea is a relatively enclosed sea between the Lau Islands and Viti Levu. There are a few islands scattered in this area. The Lomaiviti group east of Viti Levu is mostly volcanic and has well developed fringing and barrier structures. Further south, the Moala group is made up of three high volcanic islands with predominately fringing reefs around them.

Far from the main islands of Fiji are three other reef areas. In the far northwest, the island of Rotuma is volcanic and has wide fringing reefs. A number of smaller islands nearby also have fringing reef structures. In the far west Conway Reef or Ceva-i-Ra is a small coral cay of some 200 by 50 meters on a platform reef. Finally, in the southeast, Fiji claims the Minerva Reefs, although these are also claimed by Tonga.

Some of the reefs of the country have been extensively studied in terms of their ecology and biodiversity, but, given the overall extent of the Fijian reefs, a vast proportion remain poorly known, Species numbers are high, as might be expected from the location of these reefs in relation to the Indo-Pacific center of diversity as well as from the sheer variety of reef types. Some 298 species of scleractinian coral have been recorded, alongside over 475 species of mollusk and some 60 species of ascideans. A total of 1,198 species of fish have been recorded in Fiji's waters, the majority of them reef-associated.  The algal flora of these reefs is also well known, and some 422 species  have been documented.

The rural people of Fiji depend on coral reefs for the vast bulk of their protein, and subsistence catches from the reefs are estimated  at approximately 17,000 tons per year. Although fishing with hand lines is common, a vast range of techniques are used, including traps, fences, spears, gill nets, hand nets and poisonous plants (notably derris root). Some fishers also utilize scuba gear and hookah gear. Gleaning at low tide is also important for shellfish, sea cucumbers, sea urchins and octopus. Customary marine tenure at the level of individual villages has controlled utilization of reefs in many area, with villages having rights of access to fishing areas. Although such systems are still in place on many islands, there are increasing problems of overexploitation.

Nearshore commercial fisheries probably contribute a further 6,000 tons to the annual fish catch. In many areas target stocks have now declined considerably and this is largely linked to overfishing, although pollution, particularly near urban centers, may play a role. Stocks of emperors, mullets and trevally have declined, while the bump-headed parrotfish Bolbometopon muracatum have not been caught in Lau, Kadau or Vanua Levu for a least ten years. In a similar manner, collection of bivalves has long been popular as a food source and led to the extermination of the giant clam Tridacna gigas, which was last recorded over 50 years ago.

In addition to urban centers, other land based activities which threaten or degrade reefs in Fiji include mangrove clearance for land reclamation, runoff from mines, agriculture, sugar and timber mills, poorly planned tourist development and solid waste disposal. Industrial pollution is a particular problem close to Suva. On Viti Levu and Vanua Levu intensive commercial farming on steep slopes has led to considerable soil erosion. Similar problems of sedimentation which affect the coral reefs have been observed in some of the more remote and unihabitated islands as a result of overgrazing by goats.

Traditional management of reefs has led to their sustainable use throughout the archipelago for thousands of years. Although the ownership of seabed now resides with the state, the customary fishing rights of indigenous Fijians remain, under the Fisheries Act of 1942. Traditional management of reefs by the villages continues to some degree, particularly in the outer islands, and includes the setting aside (using taboos) of certain areas such as those which become overfished. Traditional fishing areas have been mapped out by the national government. Customary fishing rights have hindered the formal establishment of marine protected area and, while existing protected areas extend to the shoreline in a number of places, none incorporate sub-littoral elements. Despite this, a number of tourist resorts have established  small private sanctuaries through agreements with customary fishing rights holders.. Similarly, community-based marine reserves are being established in a few areas, with the support of the government, non-governmental organizations and local communities. These, together with the wider recognition of customary marine tenure, increasing environmental education and the establishment of reef monitoring, may well suffice to protect much larger areas of Fiji's coral reefs in the short and medium term.

OFFICIAL, SCIENTIFIC & GOVERNMENTAL SITES:
Cyber Divers News Network: Article on Fiji's reefs
Darwin Initiative: Coral Reef Conservation in Fiji
EurekAlert: Scientists help Fijian villagers conserve coral reef while earning a living from it
Jane's Oceania: Fiji Coral Coast
National Geographic: Fiji's Rainbow Reefs
Reefbase: Coral Reefs of Fiji
The Coral Reef Alliance: The Republic of Fiji

COMMERCIAL:
Macgillivray Freeman's Coral Reef Adventure: Fiji
NAIA: Fiji Scuba Diving

Extracted and adapted from The World Atlas of Coral Reefs, by Mark D. Spalding, Corinna Ravilious and Edmund P. Green, published by the University of California Press . For more complete and in-depth coverage of the topics presented in this webpage, I recommend highly purchasing a copy of this beautifully illustrated book. Just click on the University of California Press link above to do so.