GeoActiveGeoActive 507 OnlineOnline coral reefs: are they threatened by Robert Morris by mass extinction?

CHINA Key N CORAL REEFS ARE among the MYANMAR VIETNAM LAOS Coral Triangle region most biologically rich ecosystems Coral Triangle core Coral reefs on Earth. They are also one of THAILAND South , China CAMBODIA Bolinao Reef, Philippines the most threatened. They have Sea very high levels of biodiversity Kepulauan Seribu, Indonesia (a large number of species) with MALAYSIA Celebes about 5,000 species of fish and Sea Pacific Ocean 800 species of reef-building coral. INDONESIA They are also of huge economic Java Sea PAPUA NEW value, from fishing and as a GUINEA source of materials for jewellery manufacture and construction. Indian Ocean

For these reasons, and because 0 1500 km of the effects of global warming, AUSTRALIA they are massively under threat. Figure 1: The Coral Triangle

GeoActive Series 25 Issue 1 This unit deals with the threats to Fig 507_01 Mac/eps/illustrator v15 s/s Solomon Islands 97% coral reefs in the Coral Triangle NELSON THORNESProportion PUBLISHING of total national region (Figure 1) as this is where Artist: David Russell Illustration Timor-Leste 53% population within 10 km of the greatest concentration of coast and 30 km of reef reefs in the world is found. It Papua New Guinea 27% also looks at measures put into place to protect the reefs. More Malaysia 20% details on the formation and the Philippines 46% value of coral reefs can be found in GeoActive 392 ‘Caribbean Indonesia 26% Coral Reefs: an Ecosystem Under Threat’ (April 2008) – ask your 0102030405060 teacher for this. Millions Coral reefs in the Coral Figure 2: People in the Coral Triangle living near coral reefs, 2007 Triangle Source: World Resources Institute Spanning parts of Southeast Asia Over 80% of the reefs in Philippines account for a major and the western Pacific, the Coral this region are under threat, portion of these habitats. Triangle is recognised as the with 56% at high risk. The Local threats global centre of marine biological major threats toGeoActive reefs in the Series 25 Issue 1 There are a number of local diversity, with the highest coral Coral TriangleFig 507_02 are both Mac/eps/illustrator local v15 s/s diversity in the world (76% of (development of urban areas and threats affecting coral reefs all coral species) and the highest ports, overfishing,NELSON destructive THORNES within PUBLISHING the Coral Triangle. fishing practices, pollution, diversity of coral reef fishes (37% Artist: David Russell• Coastal Illustration development has generated of all species). The area within the sedimentation) and global a range of threats to nearby coral boundary of the Coral Triangle (coral bleaching and ocean reefs. Where space is limited, (shown on Figure 1) covers nearly acidification). More than 70% construction projects such as hotels 73,000 km2 of coral reefs (29% of the region’s people live are built upon reef communities. of the global total) and spans within the coastal zone (Figure Dredging of harbours and shipping parts of six countries: Indonesia, 2), putting pressure on nearby channels results in destruction of Malaysia, Papua New Guinea, the marine resources. Southeast these habitats. In many areas, coral Philippines, Solomon Islands, and Asia contains one-quarter of the is mined for limestone and sand Timor-Leste. world’s reefs. Indonesia and the to be made into cement. Shoreline

Series 25 Autumn issue Unit 507 Coral Reefs: Are They Threatened by Mass Extinction? © 2013 Nelson Thornes GeoActive Online This page may be photocopied for use within the purchasing institution only. Page 1 of 4 turns white. Ultimately, weakened N corals may die. Bleaching is a SINGAPORE frequent symptom of pollution- induced stress, as well as a response to natural factors such as changes in water temperature, salinity levels, and ultraviolet light. During El Niño events, large areas of coral reef in the Coral Triangle are severely damaged by high Jurong Cyrene reefs Labrador Island beach water temperatures, resulting in coral bleaching. Scientific studies have linked bleaching events to temporary ‘hot spots’ – local areas Pulau Salu St John’s Island Lazarus of unusually high temperatures Island The Sisters possibly caused by climate change. Pulau Pulau Sebarok Semakau • Ocean acidification – the oceans Key Pulau absorb about 25% of the carbon Land Semakau Fringing reefs Pulau landfill dioxide we release into the Patch reefs (submerged at high tide, Senang 0 5 km atmosphere every year. As the exposed at low tide) carbon dioxide levels increase with Figure 3: Singapore’s coral reefs global warming, so do the levels in the ocean. Scientists originally Source: http://coralreef.nus.edu.sg/map.htmGeoActive Series 25 Issue 1 Fig 507_03 Mac/eps/illustrator v15 s/s focused on the benefits of the ocean removing this greenhouse construction disturbs sediments,NELSON THORNES PUBLISHINGinland can damage coral reefs Artist: David Russell Illustration gas from the atmosphere. which smother corals. Runoff when they are transported by However, research has shown from farming causes the growth of rivers into coastal waters. This that there is also a downside: the algae which interferes with coral results in the smothering of corals, carbon dioxide absorbed by the reproduction. Other threats include reducing light levels and affecting ocean is changing the chemistry of hot-water discharge from power growth, and over-nutrification of the seawater by becoming carbonic stations, mine runoff and toxic coral reefs. Pollution is a particular acid. This has affected corals and waste which poisons coral reefs. threat to coral reefs near the other crustaceans as they are then mouths of many smaller rivers, as unable to take calcium from the • Overfishing affects most of the the high volume of sediment and water to help them grow. world’s reefs. At a basic level, freshwater flow naturally inhibits overfishing results in changes coral growth. in fish size and reduction in the numbers of fish and of species • Deforestation can also affect the Case Studies within coral reefs. The removal of development of coral reefs. River certain species may have a serious basins cleared of their forests The following case studies impact on ecosystems and result in and other vegetation cover are illustrate the range of threats to wholesale changes as some species vulnerable to erosion and flooding. coral reefs in the Coral Triangle increase rapidly in numbers if they During flooding events, silt and and how, in some cases, they are have no natural predators. other pollutants within these basins being resolved. are carried out to sea, affecting the • Destructive fishing – fishing using offshore reefs. improvised explosives or using The Southern Islands, cyanide and other poisonous • Marine-based pollution – in Singapore chemicals, pounding reefs with comparison with the other stress factors, oil spills and the deliberate Most of Singapore’s reefs lie off weighted bags to scare fish out the Southern Islands in close of crevices and, in deeper waters, discharge of oily ballast water by proximity to Singapore city’s trawling, all damage corals. Large passing ships pose an unknown, marina (see Figure 3). This area numbers of other species, along but probably less significant, threat with undersized target species, to coral reefs. is home to nearly 200 species may be swept up in nets or killed of hard corals. It has a large by poisons or explosives in the Global threats tourist industry, as well as some process. Most of these methods are The two main global changes commercial and sport fishing. actually illegal but often cannot be affecting coral reefs are largely fully enforced by law enforcement driven by human development. The Southern Islands reefs lie agencies. As not all fishing methods within the port limits of the • Coral bleaching – when corals are destructive, this is a lesser world’s busiest harbour, while threat than overfishing. undergo certain kinds of stress, much of the zooxanthellae (the the islands themselves support • Impact from inland pollution and symbiotic algae that provide coral oil refineries and petrochemical erosion – sediment, pesticides, and polyps with nutrients) are expelled plants. Massive land reclamation pollution from human activities from the coral tissue and the coral programmes since the 1960s

GeoActive Online Series 25 Autumn issue Unit 507 Coral Reefs: Are They Threatened by Mass Extinction? © 2013 Nelson Thornes Page 2 of 4 This page may be photocopied for use within the purchasing institution only. (resulting in nearly 1,700 fish numbers both seem to be washed up on local beaches. hectares of new land), along with increasing. Dynamite fishing, although regular dredging of shipping outlawed nationally since 1920, channels, has resulted in Despite this, the reef remains in still occurs, as well as heavy widespread sedimentation of the a critical state; coral bleaching ornamental fish collecting reefs. Underwater visibility was and ocean acidification remain and subsistence fishing. The reduced from 12 metres in the threats. Fish farming is also islands are under pressure from 1960s to 2 metres in 2000. The causing problems with pollution, developers seeking more tourism active growth zone of corals is water stagnation, and public and recreational facilities. There now confined to the topmost 5–6 access to reef resources. Incomes is no strategy to promote a metres of the sea compared with in the area are low, and many sustainable expansion of the 20 metres elsewhere. However, resources on land and sea tourist industry. Boat anchoring strict controls on sewage and are seriously overused by the and diving are damaging coral industrial waste treatment mean dense population. Ultimately, reefs. that these coral communities the greatest challenge is that do still survive despite their the population of Bolinao is The global recession has seen proximity to one of the most increasing by 2.5% a year and is visitor numbers plummet to only densely populated countries on expected to double in the next around 50,000 a year in 2011 Earth. 30 years. and this has led to a number of island resorts closing down, so The Bolinao Reef, Luzon Kepulauan Seribu, Java Sea, less pressure is put on the fragile Island, the Philippines Jakarta, Indonesia ecosystem by visitor numbers. Although the population of The Kepulauan Seribu reefs Most visitors are now wealthy Bolinao is around 75,000, only cover 108,000 hectares. This Jakartans, who mainly visit a few thousand actually fish the area, whose name means at the weekends. Oil and gas 200 km2 of reefs, but the reefs ‘Thousand Islands’, is noted for exploration, taking place close to support another 20,000 people its tropical islands, attractive the park, could pose a potential who work in fishery-related beaches and coral reefs. If you future threat. occupations. Sea urchins are a look up the following link, you popular delicacy in some parts can explore for yourself the Conclusion of the world and are caught here kind of tourist attractions that Although there are no in large numbers. Increasing have led to the rapid growth in internationally binding numbers of Filipinos have tourism detailed below: conservation targets or treaties migrated into reef areas, due to www.indonesia.travel/en/ related specifically to coral loss of farmland to development destination/240/the-thousand- reefs, a range of agreements are and land reform. They now islands in place that have helped focus harvest fish and other reef attention on these ecosystems. resources, increasing the threats. In 1995, the islands were These include The International Greater competition has led to declared a marine national Coral Reef Initiative (ICRI), widespread destructive fishing. park. Consequently, tourism which promotes the sustainable While fishermen in more pristine has grown rapidly from one management and use of coral reefs in other areas can harvest operator on a single island in reefs and related ecosystems up to 30 kg of fish per day, the 1982 to 11 operators working (mangroves and sea grass beds) Bolinao fishers have had their out of 18 islands by 1992. through a range of actions. These catches reduced to an average of There were approximately have included: about 1 kg per day. 8,000 visitors in 1991 rising to 187,000 in 2007. Some islands • The International Year of the Coral Reef (1997) Beginning in 1986, programmes have long been inhabited by were established by the villagers who depend on reef • The International Year of the Ocean University of the Philippines to and island resources, with the (1998). help the Bolinao municipality. tourism industry employing an Various projects to introduce increasing percentage of the local Both of these were used to small-scale mariculture of population. raise awareness of the threats seaweed and invertebrates to coral reefs. Until there are (shrimp farming) were Domestic sewage and industrial any internationally binding supplemented by community waste from Jakarta threaten the conservation targets or treaties, activities. Public education and area and rubbish floating on coral reefs all over the world improved law enforcement have the sea is a particular problem. will continue to be under serious led to a reduction in destructive Ballast water discharges threat. fishing, and coral cover and from boats result in tar being

Series 25 Autumn issue Unit 507 Coral Reefs: Are They Threatened by Mass Extinction? © 2013 Nelson Thornes GeoActive Online This page may be photocopied for use within the purchasing institution only. Page 3 of 4 Region Reef Reef area Threat – Severe Coastal Reef area area as % of medium thermal population in MPAs Activities (km2) global or higher stress within 30 (%) reefs (%) 1998–2007 km of reef 1 Define the following terms: (%) (’000s) ecosystem Brunei 109 <1 100 49 323 <1 biodiversity Darussalam overfishing Indonesia 39,538 16 93 16 59,784 29 destructive fishing Malaysia 2,935 1 99 9 5,065 7 coral bleaching Papua New 14,535 6 55 78 1,570 5 ocean acidification Guinea mariculture. Philippines 22,484 9 98 99 41,283 7 2 Study Figure 2. Singapore 13 <1 100 100 4,497 6 (a) What percentage of people in Solomon 6,743 3 71 82 540 6 the Philippines live within 10 km Islands of the coast and 30 km of coral Timore-Leste 146 <1 100 100 564 0 reefs? Coral 86,503 35 86 92 113,626 16 (b) What percentage of Triangle region Indonesia’s population live within 10 km of the coast and Figure 5: Threats to the countries of the Coral Triangle 30 km of coral reefs? MPA = Marine Protected Area (c) Calculate the approximate Source: World Resources Institute overall population of the Philippines and Indonesia from the information given in Figure 1 Any Road 2. (Your teacher should be able Anytown to help you with this activity.) AN1 1YT [Date] 3 Study Figure 4. (a) The Coral Triangle is a part The Minister of which three regions (including [Address of government minister] seas/oceans)? (b) Draw a bar graph to display Dear [?] the information shown in Figure 4.

Figure 4: World distribution of coral reefs Figure 6: Template for letter to a government minister Region Area (km2) Middle East 20,000 that are under threat – use the 8 Using your research in ‘Threat – medium or higher’ Activity 7, and the information Caribbean and 23,100 Atlantic Oceans column for your data. Your in this unit, answer the following teacher should advise you what question: Indian Ocean 36,100 radius to draw your circles for Why do we need to prevent the Southeast Asia 68,100 the pie charts. extinction of coral reefs? Pacific Ocean 108,000 (c) Give your map a key and a Total 255,300 suitable title. 9 Write a letter to the Prime Minister or a government 4 Explain the differences 6 Why are so few areas of coral minister, explaining why it between local and global threats reef in the Coral Triangle part should be a priority for the to coral reefs. of Marine Protected Areas? government to implement a Hint: Think about the levels of worldwide treaty protecting 5 (a) Using Figure 5, identify all development in these countries. coral reefs from further damage. the countries listed and locate Use the information from your them on a base map of the 7 Using the internet, do some research (Activity 7) and in this region. Label and colour each research on how people are unit. The format for your letter country on your map. protecting coral reefs. You will is set out in Figure 6. (b) Draw pie charts for each use this research to write an country on your map, showing extended piece of writing in the percentage of coral reefs Activity 8.

GeoActive Online Series 25 Autumn issue Unit 507 Coral Reefs: Are They Threatened by Mass Extinction? © 2013 Nelson Thornes Page 4 of 4 This page may be photocopied for use within the purchasing institution only.