1. ECOLOCY
Major endangered reef regions

The major reef areas (Biodiversity Hotspots) - 11 Hotspot regions that are specially endangered - Why are coral reefs important?

The major reef areas (Marine Biodiversity Hotspots)

Oceans cover 71 percent of earth's surface. Oceans have long been considered limitless places where human activities have little or no impact. But the coral reefs, the richest of the tropical marine habitats, are at risk of disappearing at an incredibly fast rate! Worldwide, already 25 percent of coral reefs have been destroyed or badly degraded. Some scientist reckon, that by 2020 up to 70 percent might be permanently lost.

In 2002 researchers identified global priority areas for coral reef conservation and prepared a list with the world's top 10 coral reef hotspots. These are areas rich in marine species which are found only in small area. Therefore they are highly vulnerable to extinction. These 10 hotspots contain just 24 percent of the world's coral reefs, or 0.017 percent of the oceans, but claim 34 percent of restricted-range species. An interesting fast is, that 8 of the 10 coral reef hotspots are adjacent to a terrestrial hotspot. Those are regions of the world that harbor the highest concentrations of species on land and are also at the greatest risk.

Endangered species: A high risk of extinction in the near future, in almost all cases as a result of human activities.

In addition to the correlation with terrestrial biodiversity hotspots, the paper notes that tropical reef ecosystems include "wilderness" areas, which remain far less impacted by people, are rich in species, and relative to degraded areas, still contain abundant populations of reef species that have already but disappeared from overexploited reefs.

Why 11 marine hotspots? In 2002 the global environmental group Conservation International presented a strategy to concentrate conservation efforts on these hotspots. This strategy prioritizes and targets conservation investments where they have the greatest impact. They name 25 Biodiversity Hotspots (on land and in the sea) and divided the so called Coral Triangle (Indonesia, Philippines, Papua New Guinea) in three different regions (Philippines, Sundaland, Wallacea). I therefore added another hotspot to the list from the Centers for Applied Biodiversity Science (CABS) resulting in 11 hotspots.

11 Marine Biodiversity Hotspots regions that are specially endangered

Map of Marine Biodiversity Hotspots: Click on the numbers and jump to the hotspot regions

The 11 coral reef hotspots ranked by degree of threat

The Philippines are ecologically unique in as far that there are a lot of small regions and areas (such as an island) that are highly diverse. Major threats are destructive fishing methods using explosives and poison (cyanid fishing for the aquarium trade), excessive fishing, pollution runoff from logging, agriculture and urban development. This is one of the most threatened hotspots, due to its population density. Hotspot Philippines - Descriptions and maps of dive sites in the Philippines (Zubi)

The Sundaland hotspot encompasses some 1'600'000 km2 and covers the western half of the Indonesian archipelago (Bali, Java, Sumatra, Borneo), Malaysia and a small part of Thailand. It is part of the so called Coral Triangle which is probably the most diverse coastal area on the planet having a richness of marine species and a large occurrence of endemism. Major threats are pollution from land-based sources, intensive destructive fishing (dynamite) and a growing live reef fish trade (for the aquarium trade). Hotspot Sundaland - Descriptions and maps of dive sites in Indonesia (Zubi)

The Wallacea hotspot encompasses some 346'782 km2 and covers Nusa Tenggara (Lombok, Sumbawa, Komodo, Flores, Sumba, Savu, Roti and Timor), the Mollucas and Sulawesi. Wallacea is divided from Sundaland by the Wallace's Line. Major threats are pollution from land-based sources, sediment pollution from logging, intensive destructive fishing (dynamite) and live reef fish trade (for the aquarium trade). Hotspot Wallacea - Descriptions and maps of dive sites in Nusa Tenggara (Zubi)

This hotspot encompasses the four islands (Annobón, Bioco, São Tomé and Príncipe) of the Gulf of Guinea, off the West African coast. The exact area of reef is unknown, but is likely to be less than 200 km2. There are rivers nearby, so the water is not very salty. Major threats from coastal development, sediment pollution from logging, over-fishing and a proposed coral harvesting business. Link - Hotspot Gulf of Guinea

This hotspot encompasses approximately 1'000 km2 of reef surrounding the islands of Mauritius, La Reunion and Rodriguez in the southern Indian Ocean. Major threats are the rapidly growing human population, pollution from intensive sugar cane production, coastal and agricultural development, and over-fishing.

This hotspot lies adjacent to Cape Floristic and encompasses less than 200 km2. Major threats are land-based sources of pollution, fishing and development of tourism. Hotspot Eastern South Africa

This hotspot encompasses the Maldives, Chagos islands and much of the Lakshadweep and Lakkadives archipelagoes, as well as Sri Lanka, a total of 10,000 km2. Global warming in 1998 increased the sea surface temperatures and resulted in severe coral bleaching. Global climate change continues to pose a threat, as do coral mining, over-fishing and ornamental fish collection.

Over 3,000 km2 of reefs extending from Kyushu in Japan, through Taiwan to the coast of southern China. Major threats are shoreline development (proposed airport) and conversion for agriculture and aquaculture, rapidly growing human population and also global climate change, sea warming, and plagues of coral-eating Crown-of-Thorns starfish. Hotspot Japan

Approximately 200 km2 in the mid-Atlantic off the West African coast. Major threats are coastal development, pollution from land clearing and agriculture, and over-fishing. Link

This hotspot encompasses the Caribbean islands and coastal reefs from the Mexican Yucatan Peninsula to Colombia, more than 4'000 km2 of reefs. Major threats are epidemic diseases and coral bleaching resulting from global warming and coastal development for tourism. Hotspot Caribbean

The Red Sea and Gulf of Aden hotspot extends for 2'500 km from north to south, including the Gulfs of Aqaba and Suez. Major threats are coastal and industrial developments, tourism and oil spills from tankers. The western and southern coast are less threatened.

Why are coral reefs important?

Coral reefs support the livelihoods of millions of people. They supply seafood, building materials, sources for medicinal products, and draw in much needed tourism revenue. Reefs also protect shorelines and communities from storms and erosion.

Despite their extraordinary value, coral reefs are deeply threatened by human activities and global climate change. Coral reefs are an important source of food for hundreds of millions of people, many of whom have no other source of animal protein. However especially reefs in developing countries are threatened and if human impact on reefs is not reduced there is a great danger, that some of the world's poorest people will lose an important source of nutrition, and in many cases their livelihoods.

The major reef areas (Biodiversity Hotspots) - 11 Hotspot regions that are specially endangered - Why are coral reefs important?

Coral reefs - The ocean - Reefs at risk - Coral disease - index - photo collection - starfish site map