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General (Human)

1 . Global (2008)
There has also been degradation of seagrass beds and mangrove forests throughout the FWI. The extensive seagrass beds are nursery areas for many commercial species of invertebrates and fishes, but they are paying a heavy price from continued development of harbours, marinas, artificial beaches for hotels, sand mining and especially anchor damage from yachts and cruising and freighter ships. Guadeloupe has prohibited the use of seine nets to protect the shallow seagrass habitats of juvenile fishes. There are extensive mangrove forests in the bays of Martinique and Guadeloupe has the largest forest area in the Lesser Antilles. However, only a few trees remain in St-Martin and St-Barthélemy. The mangrove forests have also been devastated by economic development, especially through land reclamation for airports, industrial areas, hotels, marinas, etc. The 2500 registered professional fishermen land about 8000 tons of seafood in Martinique and 10 000 tons in Guadeloupe, with 60-75% taken from the reefs. Ciguatera (fish toxin) has significantly limited commercial fishing in St-Martin/St-Maarten and St-Barthélemy. Parrotfish (scarids) constitute the most important fish family captured by traps or nets, however, this is a potentially worrying sign as algal grazing fish play a major role in controlling macroalgal domination of coral communities; this will affect most reefs in the French West Indies.
Source: Bouchon, C., P. Portillo, Y. Bouchon-Navaro, M. Loius, P. Hoetjes, K. De Meyer, D. Macrae, H. Armstrong, V. Datadin, S. Harding, J. Mallela, R. Parkinson, J-W. Van Bochove, D. Lirman, J, Herlan, A. Baker, L. Collado and S.C. Isaac. , 2008 , Status of Coral Reef Resources of the Lesser Antilles: The French West Indies, The Netherlands Antilles, Anguilla, Antigua, Grenada, Trinidad and Tobago . In: Wilkinson, C. (ed.). Status of Coral Reefs of the World: 2008. Global Coral Reef Monitoring Network and Reef and Rainforest Research Center, Townsville, Australia. p265-280. (See Document)

Overfishing

2 . Global (2004)
Over-fishing: As human populations increase and regional economies grow, there is a parallel increase in the demand for seafood. Most coral reefs within range of small fishing boats, including motor powered aluminum boats, are now over-fished with the key target species being those that are closely associated with coral reefs; the groupers, snappers and large wrasses. As catches for these decrease, fishers target all fish species using more efficient methods of traps, fine mesh nets and spears; the final resort is to use bombs and cyanide to catch the few remaining fish. This fishing down the food chain from the predators, to omnivores, to herbivores, and eventually to planktivores, has multiple effects on a coral reef. The removal
of fish has been likened to removing the immune system; the net effect is that coral reefs without fish are far more susceptible to overgrowth by macro-algae, plagues of coral predators, and probably increases in disease. In addition, fishing results in direct physical damage to the coral framework, thereby further exacerbating the effects of over-fishing. Damage results from anchors, nets and traps and especially the use of explosives to stun fish hiding in the corals.

There are many reefs in Eastern Africa, South and Southeast Asia and the Caribbean where it is rare to see a fish over 10 cm long. As these areas become depleted, more fishers target remote reefs and industriously remove most suitable fishes. This mobile trade in Asia is driven by an almost insatiable market demand for live-food fish from Asian restaurants. Sharks are now particularly rare on many reefs; just to make shark fin soup. These two trades are multi million dollar industries.

One of the most effective measures to protect biodiversity, including fishes, is the stablishment and enforcement of no-take MPAs. However, many national and international fisheries management authorities contend that improvement in fish abundance in areas near MPAs has to be demonstrated before more MPAs are implemented. This suggests that no-take MPAs are experiments in managing fish stocks and must be scientifically validated. The inverse is the reality. No-take MPAs on coral reefs do conserve biodiversity and retain natural ecosystems, and constitute the ‘control’ in the ‘experiment’, which is to determine whether fishing or selectively removing one component (fish) from an ecosystem is detrimental. Thus, the hypothesis should be: ‘does fishing remove fish from an ecosystem and does over-fishing affect the biodiversity and ecological balances on a coral reef’; the no-take zone then become the control for this experiment as an un-fished ecosystem.

Unless fishing pressures can be reduced through providing alternative livelihoods and employment for fishers, through sustainable aquaculture and through establishing more no-take MPAs, it is predicted that there will be more collapses in fisheries stocks. The following two boxes present
different views on the possibility of managing coral reef fisheries in developing countries. One view (Daniel Pauly and colleagues) is pessimistic and based on many observations of fisheries in the developing world, especially Southeast Asia. The other view from the International Society for Reef Studies is more sober, but does not disagree and is still pessimistic.
Source: Wilkinson, C. , 2004 , Foreword, Countries, States and Territories Acknowledgements, Co-sponsors and supporters of GCRMN, Introduction and Executive Summary. . p: I-66. in C. Wilkinson (ed.). Status of coral reefs of the world: 2004. Volume 1. Australian Institute of Marine Science, Townsville, Queensland, Australia. 301 p. (See Document)

Destructive fishing

3 . Global (2004)
Destructive fishing: Over-fishing is often accompanied by damaging practices to compensate for the depletion in fish stocks and to feed the demand for high priced species for Asian restaurants and the aquarium trade. Bomb fishing is largely restricted to Southeast and East Asia, although it has occurred in Eastern Africa and parts of the Pacific. Bombs are used when fish stocks drop making hook and line, and net and trap fishing un-profitable. Cyanide was first used to catch small aquarium fish, but it has expanded to capture live fish for the restaurant trade. The fish can be resuscitated after being stunned; although there is usually permanent liver damage. The use of cyanide, however, usually results in death of corals and other reef organisms, resulting in a wasteland.
Source: Wilkinson, C. , 2004 , Foreword, Countries, States and Territories Acknowledgements, Co-sponsors and supporters of GCRMN, Introduction and Executive Summary. . p: I-66. in C. Wilkinson (ed.). Status of coral reefs of the world: 2004. Volume 1. Australian Institute of Marine Science, Townsville, Queensland, Australia. 301 p. (See Document)

Sedimentation (anthropogenic)

4 . Global (2004)
Sediment pollution: Most developments on land and within reef catchment increase the flow of sediment onto coral reefs. Sediments are inimical as they reduce light energy for the photosynthetic corals, increase rates of disease and bioerosion, and eventually bury the corals. The rate of sediment release into the oceans is increasing, as more coastal lands are developed to accommodate rising urban populations and increases in agriculture. One of the major increases is through tropical deforestation, often by clear felling for tropical timbers and agriculture, such as oil palm plantations in Southeast Asia and the Western Pacific. These impacts are clearly being felt in Indonesia, Papua New Guinea and the Solomon Islands. In parts of Micronesia, steep upland forest areas are being cleared to grow ‘sakau’, a type of mildly intoxicating ‘kava’.
Source: Wilkinson, C. , 2004 , Foreword, Countries, States and Territories Acknowledgements, Co-sponsors and supporters of GCRMN, Introduction and Executive Summary. . p: I-66. in C. Wilkinson (ed.). Status of coral reefs of the world: 2004. Volume 1. Australian Institute of Marine Science, Townsville, Queensland, Australia. 301 p. (See Document)

Coastal development

5 . Global (2004)
Development on coral reefs: As populations increase on the coast, so do the pressures to alienate land from the sea for development. There are currently large plans to ‘reclaim’ coral reef areas in the Persian/Arabian Gulf, especially in United Arab Emirates, in the Red Sea along the coast of Saudi Arabia, in Singapore and recently in Peninsular Malaysia and southern Japan to build airports on coral reefs to attract tourists. Virtually all coastal developments result in sediment damage to fragile corals, however, some activities have long lasting effects. The building of marinas, groynes and causeways around coral reefs disrupt currents and often cause major displacements of sediment. Causeways on some Pacific islands have resulted in considerable coral death and reduced fisheries in coral lagoons.
Source: Wilkinson, C. , 2004 , Foreword, Countries, States and Territories Acknowledgements, Co-sponsors and supporters of GCRMN, Introduction and Executive Summary. . p: I-66. in C. Wilkinson (ed.). Status of coral reefs of the world: 2004. Volume 1. Australian Institute of Marine Science, Townsville, Queensland, Australia. 301 p. (See Document)

Destructive fishing

6 . Eastern Africa (2004)
ANTHROPOGENIC THREATS TO CORAL REEFS

The most common threat to reefs in East Africa are the effects of fishing, although the specific threat levels will vary at different sites e.g. the relative damage from excess harvesting, destructive gears and migrant fishermen varies. Beach seines and gill nets, and bomb fishing are typical of destructive methods that cause significant damage to habitats, juvenile fish populations and vulnerable species. The high level of effort by migrant fishing on the larger reef systems is rated as a serious problem in places such as Tanga, Tanzania. This poses specific challenges to locally-based management. The development of fisheries management practices to mitigate these threats is the primary objective in both places. There is an increasing focus on district-level opportunities for management through collaborative arrangements between local government and communities, and cross-sectoral cooperation among government institutions. Increasing human populations are the major driving force behind the increase in fishing damage. Intensive and growing pressure, combined with high isolation and vulnerable environments, such as in the Maputaland reefs of South Africa, contribute to a high threat level.(Table7)
Source: Obura, O., J. Church, C. Daniels, H. Kalombo, M. Schleyer and M. Suleiman , 2004 , Status Of Coral Reefs In East Africa 2004: Kenya, Tanzania, Mozambique And South Africa. . p: 171-188 in C. Wilkinson (ed.). Status of coral reefs of the world: 2004. Volume 1. Australian Institute of Marine Science, Townsville, Queensland, Australia. 301 p. (See Document)

General (Human)

7 . Eastern Africa (2004)
ANTHROPOGENIC THREATS TO CORAL REEFS

The most common threat to reefs in East Africa are the effects of fishing, although the specific threat levels will vary at different sites e.g. the relative damage from excess harvesting, destructive gears and migrant fishermen varies. Beach seines and gill nets, and bomb fishing are typical of destructive methods that cause significant damage to habitats, juvenile fish populations and vulnerable species.
Source: Obura, O., J. Church, C. Daniels, H. Kalombo, M. Schleyer and M. Suleiman , 2004 , Status Of Coral Reefs In East Africa 2004: Kenya, Tanzania, Mozambique And South Africa. . p: 171-188 in C. Wilkinson (ed.). Status of coral reefs of the world: 2004. Volume 1. Australian Institute of Marine Science, Townsville, Queensland, Australia. 301 p. (See Document)

Destructive fishing

8 . Eastern Africa (2002)
Over-fishing and destructive fishing, pollution, mining, deforestation and poor land management, and poorly managed and planned tourism are the major localized stresses damaging coral reefs on the Eastern African coast. Excessive and destructive fishing was the major anthropogenic problem for reefs in East Africa in the 1990s (Muthiga et al., 1998) until the damaging 1998 El Niño bleaching event. The damaging fishing practices include the use of dynamite, pull-seine nets, poisons, over-exploitation of small fish in small mesh nets and traps, and over-harvesting of octopus, shellfish, sea cucumber and lobster.
Source: Obura, D. , 2002 , Status of Coral Reefs in East Africa. . in Linden, O., D. Souter, D. Wilhelmsson, and D. Obura (eds.). Coral degradation in the Indian Ocean: Status Report 2002. CORDIO, Department of Biology and Environmental Science, University of Kalmar, Kalmar, Sweden.pp 15-20 (See Document)

General (Human)

9 . Southwest Indian Ocean (2008)
Small French Islands in the Western Indian Ocean

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There are no direct human pressures on these corals reefs as the islands are natre reserves. Thus, the threats affecting these remote islans have mostly been ‘natural’ in origin, such as the 1998 massive bleaching mortality of coral reefs in the Mozambique Channel, or crown-of-thorns starfish plagues observed on the outer slopes of Europa in 2002. Oil spills are considered a potentially serius threat for the coral reefs and associated intertidal areas as the Mozambique Channnel is the main route for tankers (from Thierry Perillo, Thierry.perillo@taaf.fr and Jean Pascal Quad, pascal.quod@arvam.com).
Source: Ahamada, S., J. Bijoux, B. Cauvin, A. Hagan, A. Harris, M. Koonjul, S. Meunier and J.P. Quod , 2008 , Status of Coral Reefs in the South-West Indian Ocean Island States: Comoros, Madagascar, Mauritius, Reunion, Seychelles . In: Wilkinson, C. (ed.). Status of Coral Reefs of the World: 2008. Global Coral Reef Monitoring Network and Reef and Rainforest Research Center, Townsville, Australia. p105-118 (See Document)

General (Human)

10 . Southwest Indian Ocean (2004)
Mining of coral sand and coral for construction has caused considerable damage to some coral reefs in the region, with most states implementing stricter legislation and licensing to control exploitation. Mauritius has banned coral sand mining. Anchor damage to corals is also considerable, and many countries are installing mooring buoys (e.g. Reunion, Mauritius) in heavily used and ecologically sensitive areas.
Source: Ahamada, S., J. Bijoux, L. Bigot, B. Cauvin, M. Kooonjul, J. Maharavo, S. Meunier, M. Moine-Picard, J.-P. Quod and R. Pierre-Louis , 2004 , Status of the Coral Reefs of the South West Indian Ocean Island States. . p: 189-212. in C. Wilkinson (ed.). Status of coral reefs of the world: 2004. Volume 1. Australian Institute of Marine Science, Townsville, Queensland, Australia. 301 p. (See Document)

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