(7-A) - Mangroves - [A1] Global, [A2] Africa, [A3] Central America, [A4] South America, [A5]~Oceania, [A6] Asian Sub-continent, [A7] Southeast Asia, [A8]~ Singapore,
(7-B) - Coral Reefs - [B1] Value, [B2] Global, [B3] Damage Mechanisms, [B4] Africa, [B5] Arabian Sea, [B6] Australia, [B7]~ Belize, [B8]~ Caribbean, [B9] Costa Rica, [B10] Florida, [B11] Southeast Asia, [B12] Jamaica, [B13] East Asia, [B14]~ Philippines, [B15] Singapore, [B16] South America, [B17] South Pacific, [B18] Indian Ocean, [B19] Oceania,
(7-C) - Estuaries and Coastal Wetlands - [C1] Value, [C2] Global, [C3] US, [C4] China, [C5]~ Europe, [C6] First World, [C7]~ Southeast Asia, [C8] Middle East,
(7-D) - Sargassum and Seagrass - [D1] General, [D2] Management, [D3] Human Uses, [D4] Role in Marine Ecosystems,
(7-E) - Freshwater Lakes and Rivers -

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NOTE: The notation (su6) means that the data is used in the document analyzing the sustainability of the productivity of the world's food, fiber and water supply systems. (See elsewhere in this website.)

Comments:
Mangrove swamps, estuaries and coastal wetlands, because of their abundance of food, are nurseries for many species of fish. 2/3 of all commercially valuable fish species spend the first stage of their life in these waters (Ref. 15 of (93W1)), (80M1). 90% (by mass) of marine animals rely on coastal areas (mangrove swamps, estuaries and coastal wetlands) for spawning grounds (Ref. 16, Ch. 5 of (94B3)).

On the order of 2/3 of commercially valuable marine species depend on coastal habitats such as estuaries, wetlands and reefs. Most of the world's major estuaries are polluted by industry, agricultural- or urban runoff, or starved of nutrients by dams (Ref. 55 of (98W1)).

SECTION (7-A) - Key Habitats/ Inventories/ Degradation - Mangroves - [A1] Global, [A2]~ Africa, [A3] Central America, [A4]~ South America, [A5] Oceania, [A6] Asian Sub-continent, [A7] Southeast Asia, [A8] Singapore

Overall it is estimated that close to 50% of the world's mangrove forests have been destroyed (95K1).

One km² of mangrove forest can sustainably produce 38 tonnes of fish per year, and provide nursery grounds for an added 48 tonnes of fish and shrimp that mature elsewhere each year. The high density, intensive shrimp ponds that are replacing mangroves produce 100-300 tonnes/ km²/ year for about 5 years, at which point the ponds must be abandoned as a result of being abandoned because they are so choked with waste that they cannot support life of any kind (Ref. 30 of (99M1)). Comments: Data seems to be lacking on the fallow period required to restore these ponds. Also the economic analysis needs estimates of the value of the storm-protection and water-regulation benefits provided by mangroves.

Globally, coastal mangroves now cover 200,000 km² (97S1). (la)

80-90% of the commercial seafood species that inhabit the world's tropical oceans spend some part of their lives in coastal mangroves (94H2).

Mangroves line 8% of the world's coastlines (Burke et al [PAGE] 2000) and about 25% of tropical coastlines, covering a surface area of 181,000 km² (97S2). (la)

Some 112 of the world's countries and territories have mangroves within their border (97S2).

About 50% of the world's mangrove swamps and salt marshes have been destroyed for farmland, fishponds or industrial developments (Ref. 55 of Ref. (98W1)).

Well over 50% of the original areas of mangroves in tropical countries have been lost (Ref. 16, Chapter 5 of (94B3)). Because of the loss of half the world's mangrove forests, the world's coastal fishers may have lost 4.7 million tons of fish/ year, including 1.5 million tons/ year of shrimp (Ref. 48 of (94W2)). Mangrove forests are being cut for charcoal, pulp, clearance for salt making, and aquaculture ponds.

Shrimp farmers (aquaculture) clear-cut mangroves and other coastal ecosystems, then bulldoze shallow pools. Drugs can control diseases in these pools for about 7 years, then the pools must be abandoned and the process repeated further along the coast. The wasteland left behind is soil-deficient and too polluted to replant (97M1). Comments: The physical elimination of soil by bulldozing suggests that the time required for recovery of these ponds to agricultural usefulness must be on the order of centuries, though the recovery for aquacultural usefulness may be less.

Tanzania has banned the destruction of its remaining 810 km² of mangroves (89L1). (la)

[A2b] - Mangroves - Africa - Niger Delta -
The Niger Delta contains the third-largest contiguous mangrove forest in the world (99M6).

Over 35,000 km² of mangrove forests have been lost thus far in the Niger Delta (99M6).

[A3] - Key Habitats/ Inventories/ Degradation - Mangroves - Central America -
[A3a] - Mangroves - Central America - Dominican Republic
Mangroves are largely gone in the Dominican Republic (93W2).

[A3b] - Mangroves - Central America - Haiti -
Mangroves are largely gone (93W2).

[A3c] - Mangroves - Central America - Jamaica -
Mangroves are largely gone in Jamaica (93W2).

[A3d] - Mangroves - Central America - Panama -
Panama lost 67% of its mangroves during the 1980s (93D1).

[A3e] - Mangroves - Antigua (Caribbean island) -
A third of the island's remaining mangroves were destroyed to make way for a resort development before local people succeeded in stopping the bulldozers (Anjali Acharya, Worldwatch, 8(6) (1995)).

Ecuador's 5-year prohibition against mangrove cutting started in 1994. It has now been extended indefinitely. 32% of the original mangrove forest still stands (99M6).

33% of Ecuador's mangroves have been converted to ponds for shrimp fishing (89L1). Shrimp farming has reduced mangrove forests by at least 25% (94H2). Ecuador has lost 800 km² of mangrove forests and salt flats to shrimp ponds over the past 23 years (94W1). 20% of Ecuador's mangrove forests were converted to shrimp farms during 1979-91 (EDF Letter, 27(1) (1996) p. 7). (la)

[A4c] - Mangroves - South America - Colombia -
Colombia has 3659 km² of mangroves, of which 80% extend along the Pacific Coast (99M6). (la)

[A5] - Key Habitats/ Inventories/ Degradation - Mangroves - Oceania - 
[A5a] - Mangroves - Oceania - Fiji
$300 million is being spent to clear mangroves on the island of Denarau to build golf courses, hotels and a marina (Anjali Acharya, Worldwatch, 8(6) (1995)).

The Indus delta region contains the world's fifth-largest mangrove forest. This forest is deteriorating markedly from rising salinity, decline of nutrients, erosion and land subsidence (93L1).

During 1963-77, almost 50% of India's mangroves were cut down (89L1).

India has lost at least 75% of its mangroves (Ref. 9 of (92R1)).

In the Bay of Bengal, 90% of the commercial fish depend on healthy mangroves for survival (98M1). India's coastal mangroves cover 15% of their original coverage (97S1).

In one coastal village in India, fishers reported a 10-fold drop in wild fish harvest one year after shrimp farms were built. In an area in Bangladesh, fishers experienced an 80% decline in wild catches after mangroves were cut down and replaced by shrimp farms that altered fresh- and saltwater flows (Ref. 116 of (98M7)).

During 1986-98, 120 km² of mangroves were replanted in the Indus Delta (Ref. 130 of (99M1)).

[A6b] - Mangroves - Asian Sub-Continent - Pakistan -
Pakistan has lost at least 75% of its mangroves (Ref. 9 of (92R1)).

In Kalimantan Province of Indonesia, 95% of all mangroves are to be cleared for pulpwood (Ref. 9 of (92R1)).

[A7b] - Mangroves - Southeast Asia - Philippines -
Aquaculture expansion in the Philippines is expected to eliminate all mangroves there in 10 years (89L1). Mangroves are over 80% gone (Ref. 25 of (93W2)).

Much of the estimated 84% of the original mangroves lost to Thailand were lost since 1975 (97M2) ((97S2), p. 66).

In Thailand, half the mangrove forests were lost in the 1980s, in large part due to shrimp farm development. The ponds yielded 120,000 tons of farmed shrimp annually, but they precipitated the loss of 800,000 tons of wild fish harvest (Ref. 116 of (98M7)).

Shrimp farming in Thailand has reduced mangrove forests by at least 25% (94H2).

Thailand has lost at least 75% of its mangroves (Ref. 9 of (92R1)).

Thailand's coastal mangroves cover 13% of their original coverage (97S1).

[A8] - Key Habitats/ Inventories/ Degradation - Mangroves - Singapore -
Almost all of Singapore's mangroves have been removed (Ref. 25 of (94W1)).

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SECTION (7-B) - CORAL REEFS - [B1] Values, [B2] Global, [B3] Damage Mechanisms, [B4] Africa, [B5] Arabian Sea, [B6]~ Australia, [B7]~ Belize, [B8] Caribbean, [B9] Costa Rica, [B10] Florida, [B11] Indonesia, [B12] Jamaica, [B13] East Asia, [14]~ Philippines, [15]~ Singapore, [16] South America, [17] South Pacific, [18] Indian Ocean, [19] Oceania,

Coral reefs are estimated to be worth $375 billion/ year by providing fish, medicines, tourism revenues and coastal protection for more than 100 countries (World Resources Inst., "Reefs at Risk: A Map-based Indicator of Threats to the World's Coral Reefs," Washington DC 1998).

(habitat) Coral reefs provide habitat for over one million species of plants and animals (97H3).

(Habitat) Coral reefs provide shelter, breeding areas, nurseries and food for shellfish, invertebrates and fish; and form an important link in cycling nutrients from the land to the open ocean (96H1).

(food) Coral reefs are the main source of animal protein for over one billion poor people in Asia (97H3).

(Coastline protection) Coral reefs protect coastlines from storm damage and beach erosion (96H1).

(Food) Reefs provide food and breeding grounds for 10% of all fish caught for human consumption (95W1). Nearly a third of the world's fish live in coral reefs (96H1).

(food) In 1986, Apo Island (in Mindanao Sea, off southern coast of Negros in Philippines) established 8% of its coral reef as a reserve, where no activities would be permitted, except scuba diving and snorkeling. By 1988 stocks of edible fish and shellfish had recovered to such an extent that the people could catch all the fish they needed around their island again (97H3).

Worldwide, an estimated 255,000 km² of shallow coral reefs exist, with more than 90% in the Indo-Pacific region (97S3). (la)

A 265-page report, "The State of Coral Reef Ecosystems of the United States and Pacific Freely Associated States," http://ens-news.com/ens/sep2002/2002-09-30-06.asp identifies the pressures that pose increasing risks to the nation's estimated 7,607 square miles (19,700 km²) of coral reefs, particularly in hot spots located near population centers. The report also assesses the health of reef resources, ranks threats in 13 geographic areas, and details ongoing efforts to mitigate damage to coral reefs.

Coral reefs have been on earth for 500 million years (Ref. 13 of (93W2)). Most coral reefs are 5,000-10,000 years old (96H1). Coral reefs occupy 0.17% of the Earth's surface, but are home to 25% of all marine fish species (Ref. 6 of (93W2)). 109 countries have shores lined with reefs. The total length of these reefs exceeds 100,000 km (93W2). Roughly 414,000 km² of coral reefs are scattered throughout the world's tropical and sub-tropical seas (96H1). (la)

10% of the world's coral reefs are degraded beyond recognition, and 30% in critical condition (97H3).

(pollution) Approximately 5-10% of the world's coral reefs have been essentially destroyed by pollution and direct destruction, and another 30% are threatened (Ref. 55 of (98W1)).

Coral reefs are among the largest and oldest living communities of plants and animals on earth, having evolved between 200-450 million years ago (97H3). Today, most established coral reefs are 5,000-10,000 years old; many of them forming thin veneers over older, much thicker reef structures. Most of the reef colony is actually dead. Only the upper layer is covered by a thin changeable 'skin' of living coral (97H3).

Scientists estimate 600,000 km² of coral reefs are scattered throughout the world's tropical and sub-tropical seas (97H3). (la)

Only reefs in remote regions of the world are generally healthy (93W2).

Coral grow from just below sea level down to 30 meters, at which point the light (needed to power the algae (zooxanthellae) which supply coral with food and oxygen) becomes insufficient (93W2).

A map of the world's coral reefs is shown in Ref. (93W2). This map categorizes reefs as "critical" (loss in 10-20 years), "threatened" (loss in 20-40 years) or "stable".

The loss of 5-10% of the world's coral reefs translates to a loss of fish on the order of 250,000-500,000 tons/ year (Ref. 49 of (94W2)).

Destruction of coral reefs has reduced potential global fish catches by $80 million/ year (89L1). Reefs off at least 80 countries are threatened by over-fishing (Ref. 36 of (93W2)). The total catch from reefs is estimated at 4-8 million tons/ year - about 10% of the fish caught for use as human food (93W2).

Coral reefs account for 20-25% of fish caught by developing countries (Ref. 11 of (93W2)). 4 million small-scale fishers - 1/3 of all subsistence fishers - obtain their catch from coral reefs (Ref. 12 of (93W2)).

Pacific islanders obtain up to 90% of their animal protein from reef fish (Ref. 10 of (93W2)).

Southeast Asian coral reefs can support 5-15 times the number of fish found in the entire North Atlantic (96H1).

70-90% of all fish caught by coastal fishermen in tropical Asia are reef-dependent at one time or another in their life (96H1).

The status and decline of the world's coastal reefs are documented in Ref. (94W2).

Clive Wilkinson, a coral reef expert working at the Australian Institute of Marine Science in Townsville insists that if nothing is done in time to conserve and manage coral reefs, the world may well lose 70% of them within 40 years (97H3).

10% of the world's reefs are dead or damaged beyond the capacity to recover, according to US Government reports (95W1). At the current rate of loss, an added 30% will disappear in the next 2 decades (95W1).

People have, directly or indirectly, caused the death of 5-10% of the world's living reefs, and at current rates, will destroy another 60% in the next 20-40 years (Ref. 19 of (93W2)).

A study from the World Conservation Union and UNEP in the mid-1980s (Ref. 4 of (93W2)) found that people had damaged or destroyed significant amounts of reef off the coasts of 93 countries (93W2).

If trends continue, within 4 decades only 155,000 km² of the world's 600,000 km² of coral reefs will be left intact and functioning (Reference citation apparently lost.) (la)

10% of the world's reefs have been degraded "beyond recognition"; 30% are in critical condition and will be lost completely in 10-20 years if trends continue; another 30% are threatened, and will be lost within 20-40 years if trends continue (96H1).

93% of the 109 countries with significant coral reefs were damaging them (96H1).

(* incl.Hawaii)

(general) 58% of the world's coral reefs are potentially threatened by destructive fishing practices, tourist pressures and pollution ((98B3), p. 6).

(general) Many coral reefs around the world are increasingly threatened, principally from over-fishing, excessive inputs of sediments and nutrients from human activity (pollution, deforestation, reef-mining, dredging) (94H4). Reefs are being excavated for use in cement, killed off by industrial pollutants, smothered by sediment eroded from cleared land, and choked by untreated sewage. Coral reefs are susceptible to these disturbances because they depend on sunlight (96H1).

(fishing practices) Coral reefs are destroyed by fishermen using dynamite and poisons, damaged by fine mesh nets and boat anchors dropped carelessly on coral heads, excavated for use in cement production and used as road fill, killed off by pollutants pumped into coastal waters by industries, smothered by eroded sediment off the land, and choked by untreated sewage and municipal wastes flushed into coastal waters by urban areas and tourist resorts (97H3).

(fishing practices) Commercial pressures force subsistence fishermen into a destructive cycle of dynamite, poisons and fine mesh nets. According to Daniel Pauly, a fisheries biologist working with ICLARM in Manila, these fishing techniques are now the most common forms used in Southeast Asia, South Asia and East Africa (97H3).

(fishing practices) Cyanide fishing on coral reefs (highly destructive to such reefs) is used to capture live wrasses that go for thousands of dollars in fancy restaurants in Southeast Asia (Ref. 27 of (98W1)).

(fishing practices) Two trends are behind the rise in cyanide fishing: the aquarium trade began to pay big bucks for tropical reef fish, and restaurants in Southeast Asia and China began to specialize in live reef fish (97H3).

(Coral Bleaching) none before 1979. In 1987, 1991 and 1996 mass bleachings were observed in 6 of the 10 major coral provinces of the world. From late 1997 through mid-1998 bleaching was observed in all 10 provinces ((99H4), p. 8). Comments: Coral bleaching is commonly associated with high water temperatures.

(Coral Bleaching) The increasingly widespread phenomenon of "coral bleaching" occurs when corals lose the symbiotic algae which provide them with color and nutrition; corals can survive if the bleaching is brief, but if prolonged, the result is frequently death. A natural occurrence, the phenomenon is becoming more frequent and widespread. Indeed, according to the State Department report, in 1998 "coral reefs around the world appear to have suffered the most extensive and severe bleaching and subsequent mortality in modern record." The extent of the damage was so great that "even under the best of conditions, many of these coral reef ecosystems will need decades to recover" (99A2). The report notes that, the same year, "tropical sea surface temperatures were the highest in modern record, topping off a 50-year trend for some tropical oceans." It appears, the report continues, that "only anthropogenic global warming could have induced such extensive coral bleaching simultaneously throughout the disparate reef regions of the world" (99A2).

(Coral Bleaching) Record high sea temperatures resulted in the destruction of up to 70% of the world's coral reefs. A report issued by the US State Department found global warming and El Nino resulted in coral reefs "suffer[ing] the most extensive and severe bleaching and mortality in the modern record." The NMFS wants to list staghorn and elkhorn corals for protection under the Endangered Species Act. Both species are suffering from disease and bleaching caused by high sea temperatures (3/5/99 Washington Post).

A statement by the International Society for Reef Studies (ISRS), consisting of over 750 members in 50 countries, concentrates on a series of epizootics afflicting (coral) reef systems worldwide (99A2).

(over-fishing) When artisan fishermen over-harvested parrot fish and sea urchins on reefs around the Cook Islands in the South Pacific in the mid-1980s, opportunistic algal growth smothered the coral, killing the polyps. Parrot fish and urchins clean the coral of excess algae (97H3).

(pollution) Pesticides, silt and fertilizer-runoff all reduce reef health (95W1). The primary destroyer of reefs is sedimentation from logging, farming, mining, dredging, and other coastal activities (Ref. 22 of (93W2)).

(pollution) Coral reefs are often protected from sediments by mangrove forests. Thus the elimination of mangroves also threatens coral reefs (93W2).

(pollution) Eutrophication destroys coral reefs because algae that compete with coral for open spaces on the reef grow faster than coral when fertilized, and because eutrophication keeps sunlight from getting to the coral (93W2).

(fishing practices) As demand for live fish accelerates in Asia, the price for some reef fish, like groupers and humphead wrasse, has soared to $60/ pound, fuelling an epidemic of cyanide fishing. It is now so widespread that the trade in live reef fish in Southeast Asia is 20,000-25,000 tonnes/ year, worth more than one billion dollars (97H3).

Some coral islands have been demolished in the pursuit of fish by blasting (93W2).

Off east Africa, over-fishing produced an outbreak of rock-boring sea urchins that undermined the structure of corals and reefs (93W2).

Over-fishing of lobster and sea urchins may be resulting in algal overgrowth (of coral) and the subsequent depression of the valuable abalone fishery (98D2).

(Disease) In the Arabian Gulf, the newly discovered yellow-band disease is affecting up to 75% of the coral colonies in local populations (99A2).

The Great Barrier Reefs are among the best off in the world due to the protective status of a 350,000-km² park (93W2).

Great Barrier Reef Marine Park (established in 1975) covers nearly 238,000 km² (96H1). (la)

(Fish/ coral interactions) Over-fishing of predatory fish is believed to have caused outbreaks of crown-of-thorns starfish that did massive damage to Australia's Great Barrier Reef (95D1).

Reefs in Belize are among the world's best-off, due to low population-density (93W2).

Up to 75% of Caribbean coral reefs are in serious decline or under threat (UNEP studies)(96H1).

Removal of most herbivorous reef fish from some Caribbean coral reefs during a natural die-off of algae-eating urchins caused algae to over-grow corals, resulting in large-scale coral mortality (Mercedes Lee, (mlee@audubon.org) 4/14/98 post to (aoc-fishlink@igc.org)).

Along Costa Rica's Caribbean coast, sediments from local rivers have killed 75% of the coral reefs (by blocking sunlight) (89L1).

(Coral Protection) On 10/29/99, NOAA officials, upon recommendation by the Caribbean Fishery Management Council, announced the establishment of the Hind Bank Marine Conservation District off the US Virgin Islands. To protect 16 sq. miles of coral reef, fishing, vessel anchoring, and coral harvesting will be banned in this District. On 11/3/99, scientists at the US Coral Reef Task Force meeting approved a resolution calling on the US government to ban fishing from 20% of the 10,540 square miles of US coral reefs by 2020 (99B1). (la)

(Salinity) Declines in reef health (Florida's coral reef system is the third-largest on Earth.) has been attributed to increasing salinity as a result of fresh water diversions for agriculture and urban developments north of the Everglades (95W1).

(Diseased Coral) The number of areas of the 2800 mi² Florida Keys National Marine Sanctuary with diseased coral increased by 276% during the past year (94 of 160 monitoring stations, compared to 25 stations last year). The number of coral species affected by disease increased 211% (Pittsburgh Post Gazette, 11/18/97).

(Fish/ coral interactions) Declines among herbivorous fish in the Florida Keys and Caribbean coral reefs may be leading the declines of coral because herbivorous fish are needed to keep algae growth on coral reefs in check (98D2).

The Indonesian Institute of Science says 7% of coral reefs surrounding Indonesia's 17,000 islands are in good health; 30% are dead, and the rest are in critical condition (98S1).

Studies on Jamaica's coral resources over the past two decades charted the nearly complete destruction of Jamaica's coral resources. Coral cover has been reduced from an average of 52% to 3% around the entire island (97H3).

It is probable that global reef-growth is being outpaced by reef degradation (Ref. 1 of (94H4)) of the type seen extensively in Jamaican coral reefs (94H4).

Coral reefs fringe most of Jamaica's north coast along a narrow (less than 1-2 km.) belt, and occur sporadically on the south coast on a greater-than-20 km. shelf. Seagrass beds and mangroves are often closely associated with these reefs, and these provide significant nurseries for commercially important reef fisheries (Ref. 4 of (94H4)).

The effects of over-fishing, hurricane damage and disease have combined to destroy most coral, whose abundance has declined from over 50% (of original) to less than 5% today (94H4). (Damage from hurricanes, normally repaired naturally in a short time, is now permanent due to anthropogenic changes in coral reefs (94H4).) Jamaica's reefs were extensively damaged by the late 1970s from the direct and indirect effects of over-fishing to the extent that two subsequent hurricanes and the die-off of Diadema (a fish that consumes algae) were sufficient to cause a radical shift from coral to algae (94H4). Clearly, current stocks of herbivorous fish are not capable of reducing algae abundance in the absence of Diadema (Refs. 10 and 29 of (94H4)). Other echinoids have not increased in abundance in the absence of Diadema (94H4). On the southern coast the number of motorized canoes doubled from the 1970s to the mid-1980s (Ref. 8 of (94H4)), but the catch remained constant over this 15-year period. The marked changing species composition of the fishery also indicates severe over-fishing (Refs. 6-8 of (94H4)).

Munro (Ref. 7 of (94H4)) showed that, by the late 1960s, fish biomass had been reduced over the past decade by up to 80% on the fringed reefs of Jamaica's north coast, mainly by artisan fish-trapping. By 1973 the number of fishing canoes deploying traps on the north coast was 1800 (3.5 canoes/ km² of coastal shelf) -2-3 times the sustainable level (Ref. 7 of (94H4)).

Normally, after a hurricane, the regeneration of a healthy coral reef system is facilitated by rapid colonization of larval recruits, but in Jamaica, this crucial recovery mechanism has been hindered by over-fishing which contributes to prolonged macro-algal blooms that cause recruitment failure in coral (94H4). Algae recover fully within a few weeks of a hurricane. Thus future hurricanes are likely to act in ratchet fashion to further depress coral abundance and favor the shift from coral to algae (94H4).

In Jamaica, one of the most detailed studies ever of coral reef decline found that coral cover declined from 52% to 3% across the entire island during a 17-year period ending in the early 1990s (96H1).

[B13] - Key Habitats/ Inventories/ Degradation - Coral Reefs - East Asia -

[B13a] - Coral Reefs - East Asia - Okinawa -
Japanese sea urchins and sponges eat Okinawa's reefs faster than they grow (Ref. 36 of (93W2)).

[B13b] - Coral Reefs - East Asia - Taiwan -
Acid and explosives used by Chinese and Hong Kong fishermen are destroying coral beds in a Taiwan-controlled area of the South China Sea. Up to 90% of the coral has died in some beds of the Pratas island group. Biologists estimate that 50 tons of acid, used to stun fish so that they can be captured live and served freshly killed in restaurants, are sprayed into the water each year. (GREENLines Issue #623, 5/10/98, Defenders of Wildlife, rfeather@defenders.org)

By 1981, 70% of coral reefs in the Philippines had been damaged (many beyond recovery) by the cumulative effects of cyanide poisoning, mine tailings, pesticides and erosion sediments (blocking sunlight) (89L1). A sixth of the reefs off the Philippines have been damaged by blasting since 1945 (Ref. 42 of (93W2)). 5% of reefs are in pristine condition, 30% are largely dead, and 39% have only 25-50% covering of healthy corals (93W2). In a 10-year study the Philippine government estimated that 71% of the nation's reefs were in "poor to fair" condition; 6% were judged excellent (Ref. 11 of (92R1)).

A survey in the early 1980s found that 20% of Philippine reefs were still in pristine condition (96H1).

[B15] - Key Habitats/ Inventories/ Degradation - Coral Reefs - Singapore -
All but 5% of Singapore's coral reefs are degraded (Ref. 25 of (94W1)).

Less than 2% of Singapore's reefs are in good shape (Ref. 26 of (93W2)).

[B16] - Key Habitats/ Inventories/ Degradation - Coral Reefs - South America -
Coral reefs in Morrocoy National Park (Venezuela) turned gray and died four years ago, probably due to toxic wastes dumped by ships.
(See "Poor Protection Allows Destruction of Venezuela's Exotic Wildlife", 12/23/99 AP.

Some reefs are dying because energy-providing algae that live inside coral cells are dying of disease. A bacterium that began killing reef algae in the Cook Islands of the South Pacific in 1993 has spread more than 5,900 km. Reefs surrounding Fiji (disease-free in 1992) are now 100% infected by the disease (95W1).

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(7B) Top of this Section-Coral Reefs
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(12) Top of this Review's Reference List
(FI) Fishery Degradation: A Global Perspective (Table of Contents)
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SECTION (7-C) - ESTUARIES and COASTAL WETLANDS - [C1] Value, [C2] Global, [C3] US, [C4] China, [C5] Europe, [C6]~ First World, [C7] Southeast Asia, [C8] Middle East,

[C1] - Key Habitats/ Inventories/ Degradation - Estuaries/ Coastal Wetlands - Value -

The economic value of estuarine habitat is about $14 billion/ year (in the US??) (92S2).

Estuaries, when healthy, are among the most productive natural systems on earth. Estuaries are also visited and vacationed in by over 180 million Americans annually - about 70% of the US population (1993 figures). Fishing, tourism and recreational boating - which depend on vibrant and productive estuaries - provide more than 28 million jobs for our nation. Commercial and sport fishing alone contribute $111 billion yearly to the nation's economy. (Reference misplaced)

An "out-welling hypothesis," suggests that organic material emanating from estuarine salt marshes finds its way to offshore waters, where it provides nutrients to animals living there. This would make estuaries another kind of nutrient source for ocean life in addition to the upwelling zones off California, Africa and Chile (99C1).

As much as 90% of all fin- and shellfish depend on estuaries for some portion of their life cycle or for wetlands-produced food (77M1), (84T1), (79P1).

Estuaries have many different types of habitats - vital to many important species of plants, fish, and other wildlife, including 75% of the commercial fish catch and 80-90% of the recreational catch of fish (Reference misplaced).

Coastal wetlands serve as feeding and nursery grounds for 65% of the commercial fish in US waters (84L1). Of the ten fish and shellfish most valuable commercially - shrimp, salmon, tuna, oysters, menhaden, crabs, lobsters, flounder, clams and haddock - only tuna, lobster and haddock are not estuary-dependent (66M1).

Sharks are fundamentally dependent on coastal estuaries and bays - areas that are not under federal jurisdiction-for bearing their young and for nursery grounds. Sharks take several years to reach maturity and produce only a few off-spring (98C2).

Scientific studies have demonstrated a direct correlation between the amount of coastal marsh and shrimp production (84T1), (77T1).

Since the early 20^th century, nearly 50% of the world's coastal wetlands have been filled in or severely degraded (Ref. 28 of (99M1)).

During 1989-1998, Korean developers filled in 400 km² of coastal wetlands in Kyunggi Province to create urban developments (99M1).

Development has destroyed 50% of all coastal wetlands in the world (Ref. 48 of (94W2)). Globally, shrimp ponds have consumed 27,000 km² of coastal ecosystems (Ref. 14 of (97A1)). (la)

In the southeastern states (US) where coastal habitat losses are extensive, seafood landings declined 42% during 1982-91 (92S2).

Ongoing coastal wetland losses cost US fisheries an estimated $208 million/ year in reduced catches (92S2).

About 70% of the US fish catch is made up of species that depend on estuaries for at least part of their life-cycle (94S1).

(US Generally) The National Estuary Program (US) was established in 1987 to direct greater federal attention to these important waters and to develop actions to restore the ecological integrity to these areas. Today, 28 nationally significant estuaries are part of the program. 17 of these have completed and secured EPA approval of their comprehensive estuary plans. (Ted Morton, American Oceans Campaign, 9/10/97, Ted.Morton@radagast.wizard.net).

(U.S. generally) The level of habitat loss in some US estuaries is approaching 80-95%. So fish catches are at their lowest, shellfish beds are closing. As an example, in the Chesapeake Bay over a period of 30 years (1959-89), oyster harvest fell from 25 million pounds to 1 million because of the loss and degradation of essential habitat (Reference misplaced).

(Chesapeake Bay) Chesapeake Bay's oyster catch fell from 20,000 tons/ year in the 1950s to under 3,000 tons/ year in the late 1980s, at least partly as a result of pollution (Ref. 24 of (93W1)).

Scientists have gathered increasing evidence that estuaries like Chesapeake Bay and North Carolina's Pamlico and Albemarle sounds are being degraded by nitrogen from agricultural operations, lawn fertilizers and sewage, the destruction of wetlands for construction projects and other causes. Excess nitrogen can cause microscopic plants to "bloom" explosively in estuarine systems and then rob the water of oxygen when they die and decay (99C1).

25% of US estuarine waters that have been tested have elevated levels of toxic substances (EPA Journal, Sept.-Oct.1990).

(Georgia) River swamps in Georgia produce 1,300 lb. of fish/ acre/ year (84T1, 70W1). Marshes along Lake Michigan are spawning grounds for northern pike, yellow perch, carp, smallmouth bass, largemouth bass, bluegills and bullheads (84T1), (78J1).

(Pacific Northwest) In the Pacific Northwest, coastal wetlands along spawning streams are vital to many salmon species (84T1), (79M1).

(Southeastern US) About 80% of commercially important seafood species along the Southeastern US spend parts of their lives in estuaries, brackish coastal nursery areas that show signs of being degraded by human activities. When salt marsh habitat and production is lost, when estuarine creeks and rivers are anoxic (oxygen depleted), when seagrass beds disappear, those things tell us that the habitat on which these organisms depend is being degraded (99C1).

Two thirds of commercially important fish and shellfish harvested along the Atlantic coast and in the Gulf of Mexico depend on coastal estuaries and their wetlands for food sources, for spawning grounds, and for nurseries for the young. (78H1), (66M1) For the Pacific coast of the US the corresponding figure is almost 50% (78H1), (66M1).

(Atlantic Coast) Along the US Atlantic coast, stocks of menhaden (a species that depends of coastal wetlands for nursery habitat and food) have declined by 26% in 10 years, in part due to the loss of coastal wetlands (98M1).

(Louisiana) Four million acres (16,000 km²) of ponds, bays and estuaries in Louisiana supply millions of dollars worth of oysters, shrimp and crabs. (82N1) ((84T1) p. 23) During 1956-75, 60% of US commercial fish- and shellfish landings were species that depend on wetlands (84T1), (79P1).

E. P. Odum has computed the monetary value for preserved marshlands and estuaries of the South Atlantic and Gulf Coasts in terms of fishery nurseries, aquaculture potential and wastewater treatment at $82,000/ acre (76U1).

Shrimp and menhaden, which make up 95% of Louisiana's commercial fishery (0.85 million tons/ year) and 25% of the US total commercial fishery, depend on coastal wetlands during part of their life cycle (82N1)? Louisiana's multi-million dollar commercial in-shore shrimp fishery is directly proportional to the area of intertidal emergent wetlands ((84T1) p. 37).

Freshwater wetlands in Georgia yield 75 lb. of fish/ acre/ year (Ref. 13 of Ref. (78H1)).

In Connecticut's marshy Niantic River, the scallop harvest is 15,000 bushels/ year, i.e. 300 lb./ acre/ year - exceeding beef yield on excellent grazing land (Ref. 14 of Ref. (78H1)). Comments: 1 bushel = 0.036 m³.

[C4] - Key Habitats/ Inventories/ Degradation - Estuaries/ Coastal Wetlands - China -
Pollution of bays and estuaries reduces China's marine catch by 210,000 tons/ year (94W2).

95% of Italy's coastal wetlands are gone (Ref. 16, Ch. 5 of (94B3)).

[C6] - Key Habitats/ Inventories/ Degradation - Estuaries/ Coastal Wetlands - First World - 
In industrial countries, over 50% of wetlands have been lost (Ref. 16, Chapter 5 of (94B3)).

[C7a] - Estuaries/ Coastal Wetlands - Southeast Asia -Indonesia -
Destruction of Indonesia's coastal habitats has eliminated 60-80% of the commercially valuable fish species (Ref. 48 of (94W2)).

46% of Indonesia's peat swamp is believed to have been lost (97M2).

[C7b] - Estuaries/ Coastal Wetlands - Southeast Asia -Vietnam - 
As much as 98% of Vietnam's peat swamp is believed to have been lost ((97M2), p. 175).

Destruction of nursery areas by land reclamation and coastal pollution is one cause of the decline of shrimp catches in the vicinity of the Persian Gulf and the Arabian Sea (Ref. 16 of (85B1)).

Egypt's Aswan Dam reduced phytoplankton in the Nile Delta by 90%, reducing the sardine catch from 18,000 tons/ year in the early 1960s to 600 tons/ year in 1969 (Ref. 47 of (94W2)).

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SECTION (7-D) - Sargassum and Seagrass - [D1] General, [D2] Management, [D3] Human Uses, [D4] Role in Marine Ecosystems

[D1] - Key Habitats/ Inventories/ Degradation - Sargassum and Seagrass - General -

(Sea Grasses) During 1983-94, more than 900 km² of sea grasses were destroyed in temperate areas. One km² of eel grass generates about $40 million worth of nutrient cycling benefits for the marine food web. So this 900 km² of lost sea grasses represents an economic loss of about $36 billion (Ref. 31 of (99M1)). (la)

(Sargassum) The South Atlantic Council in December 1998 approved a two-year phase out of sargassum collection off the North Carolina coast. Activists from the Center for Marine Conservation, the Environmental Defense Fund and ReefKeeper International spoke in favor of banning the harvest of the seaweed, which is used as habitat by 100 species of fish, more than 200 species of invertebrates, by juvenile sea turtles and migratory sea birds. Sargassum circulates from the Sargasso Sea throughout the western Atlantic hundreds of miles offshore. A North Carolina company collects the seaweed to produce agricultural products, including fertilizer and animal dietary supplements. The benefits of these supplements are unclear, said Michelle Duval of EDF. The only company known to take sargassum, it has harvested 10 tons/ year since 1976. The council capped the harvest at 25 tons/ year until 1/1/01, when it will be banned outright (99U2).

(Seagrass) Worldwide loss of seagrass because of pollution could result in "underwater prairies turning into marine deserts". Among species most affected: prawns and lobsters. Especially hard-hit are the 20,000 square miles of Australian seagrass beds that contain "half the world's estimated 70 species" of sea grasses (Reuters 3/27/00).

(Seagrass) In the US, more than 50% of the historical seagrass cover has been lost from Tampa Bay, 76% from the Mississippi sound, and 90% from Galveston Bay due to population growth and water-quality changes (99N2).

(Seagrass) Over-fishing of wrasses and triggerfish off the coast of Haiti, the US Virgin Islands and Hainan China caused an explosion in sea urchins that over-grazed the areas' seagrass beds to the point of obliteration (Mercedes Lee, (mlee@audubon.org) 4/14/98 post to (aoc-fishlink@igc.org)).

[D2] - Key Habitats/ Inventories/ Degradation - Sargassum and Seagrass - Management of Sargassum -
The SAFMC has responsibility under the federal Magnuson-Stevens Act for managing fisheries and fish habitats in the South Atlantic Exclusive Economic Zone, from 3 miles out to 200 miles (98D3).

In US East Coast waters, one firm (Aqua 10 Laboratories, Carteret County NC) has conducted low-level, variable harvest of Sargassum for 20 years. Over that period, a total of 450,000 pounds (wet weight) has been collected. The company makes a variety of products, including agricultural fertilizer additives and swine and poultry feed amendments, and is currently touting the material for treating swine waste (98D3).

Sargassum in the South Atlantic Bight on the US East coast is derived from the Sargasso Sea, located in international waters in the quiet zone between major oceanic current systems, hundreds of miles offshore. Currents entrain Sargassum masses, which may then travel inshore, depending on the vagaries of the Gulf Stream and associated warm core rings, ultimately being deposited on US beaches or drifting into the North Atlantic or beyond. Sargassum reproduces principally through fragmentation. Its productivity offshore is limited by low nutrient availability (98D3).

The floating seaweeds in the genus Sargassum form a critically important habitat for a wide array of marine organisms in the Western Atlantic Ocean. Sargassum forms the "weedlines" so sought after by offshore fishermen. A spectacular array of biota is closely associated with Sargassum at some stage of their life history: over 100 species of fish (including billfishes, dolphin, jacks, triggerfish, snappers, and many others) and over 200 species of invertebrates. Juvenile sea turtles (4 species) live in Sargassum mats; migratory seabirds depend upon them for forage sites. In the nutrient poor open ocean, Sargassum is a unique source of organic matter and of structure, and the linchpin of a complex oceanic ecosystem. Many species are obligatory Sargassum residents, in at least some life history stages (98D3).

In late 1998, the SAFMC voted to phase out the allowable 'harvest' of Sargassum, allowing the collection of 50,000 pounds "landed weight" until 1/1/01 when all collection will be prohibited (pending NMFS approval of the SAFMC action). The quota was set at a level significantly higher than recent collection levels (98D3).

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