CHAPTER 5 ~ SUSTAINABILITY OF OUTPUTS OF THE WORLD'S FISHERIES ~
Note: The data found below represent a sampling of a much larger collection of data compiled in "Fishery Degradation: A Global Perspective" found on this same website.
~ TABLE OF CONTENTS: ~
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A |
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B |
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C |
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D |
OVER-FISHING GENERALLY ~ [D1]~ All Trophic Levels, [D2]~ High Trophic-Level Fisheries, [D3]~ Low Trophic-Level Fisheries |
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E |
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F |
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G |
FISHERY MANAGEMENT PROBLEMS FACED BY DEVELOPING NATIONS THAT THREATEN FISHERY SUSTAINABILITY |
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H |
DEGRADATION AND SUSTAINABILITY OF ESSENTIAL FISH HABITATS ~ [H1]~ General, [H2]~ Mangroves, [H3]~ Reefs, [H4]~Coastal Estuaries and Wetlands, [H5]~ Continental Shelves, [H6]~ Seagrasses, |
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I |
SUSTAINABILITY OF AQUACULTURE ~ [I1]~ Background, [I2]~ Fishponds, [I3]~ Marine Cages, [I4]~ Fishmeal and Fish Oil |
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J |
REFERENCES (fi12.html) |
Go to Table of Contents
of this Entire Document on Sustainability Issues (in the Introductory Chapter)
Go to home page of this website ~
Go to Introductory Chapter of this Sustainability Document ("Sustainability - Definitions, Context, Politics, History and its Role in the Evolution of Human Cultures")
Go to Chapter 1 of this Sustainability Document ("Sustainability of the Outputs of the World's Soils and Croplands")
Go to Chapter 2 of this Sustainability Document ("Sustainability of the Outputs of the World's Forest Land")
Go to Chapter 3 of this Sustainability Document ("Sustainability of the Outputs of the World's Grazing Lands")
Go to Chapter 4 of this Sustainability Document ("Sustainability of the Outputs of the World's Irrigated Lands and Freshwater Supplies")
Section [A] ~ ELEMENTS OF NON-SUSTAINABILITY ~
Summary of Major Sustainability Problems Affecting Wild Fisheries and Aquaculture: (Details and Data follow that.)
Go to this Chapter's Table of Contents ~
Section [B] ~ THE THEORETICAL LIMITS TO THE PRODUCTIVITY OF THE WORLD'S AQUATIC SYSTEMS AND THE EFFECTS OF DIFFUSENESS
The primary production required to sustain the world fisheries catch (94.3 million tonnes/ year in 1988-91 + 27 million tonnes/ year of discarded by-catch (Ref. 4 of Ref. (95P2))) amounted to 8% of global aquatic primary production, nearly 4 times the previous estimate. By ecosystem type, the requirements were 2% for open ocean systems, but 24-35% in fresh water, upwelling and shelf systems (95P2). Catches by artisan and subsistence fishers are probably largely neglected here.
An estimated 8% of total aquatic primary production (137,000 million tonnes (dry-weight)/ year) is needed to sustain capture fisheries, seaweed collection and aquaculture; this proportion ranges from 2% in the open ocean to 24-35% in freshwater, shelf and upwelling systems (Ref. 19 of Ref. (00N1)). Global capture fisheries (plus aquatic plants) remove 123 million tonnes/ year from seas and lakes (Ref. 20 of Ref. (00N1)), of which 27 million tonnes/ year is directly discarded as bycatch (Ref. 21 of Ref. (00N1)).
The estimated aquatic primary productivity required by fish harvested in the shelf systems ranged from 24.2 to 35.3% of aquatic primary productivity. This is mainly due to industrialized fisheries operating at high trophic levels (25.1% for upwelling systems) (95P2).
The bulk of aquatic primary productivity (75%) occurs in the open ocean (gyre) system (95P2). The problem is that this production is so diffuse (See a table below) that capture costs are often prohibitive. So the potential for increasing the productivity of the open ocean to significantly more than the current 2% of primary production is very limited. Large open-ocean species at high trophic levels (e.g. whales, tuna, swordfish, marlin) are generally heavily over-fished.
Studies around 2004 show that larger, older fish produce more eggs and surviving offspring than younger fish, researchers said in February of 2005, adding that policymakers need to protect broader swaths of the ocean to preserve these efficient spawners. Steven Berkeley, a research biologist at the University of California at Santa Cruz who described his findings at the annual conference of the American Association for the Advancement of Science in Washington, said sustained over-harvesting of Pacific rockfish and other species is undermining these populations' ability to recover. Berkeley found that a 31.5-inch Bocaccio rockfish produces 10 times as many larvae as one that spans nearly 20 inches, and the larger fish's offspring were more than three times as likely to flourish (05E1). This would suggest that as over-fishing continues, the rate of decline of the over-fished fishery would increase at a rate larger than what a calculation that ignores the fish-age issue would compute.
Global estimates of aquatic primary production (PP) (grams carbon/ m2/ year) catch and discards (both in grams/ m2/ year based on 1988-91 FAO data) (T. L. = Trophic Level) (Areas are in millions of km2) (95P2).
|
Ecosystem Type |
Area |
PP |
Catch |
Discard |
T.L. |
|
Open ocean |
332.0 |
103 |
0.01 |
0.002 |
4.0 |
|
Up-wellings |
0.8 |
973 |
22.2 |
3.36 |
2.8 |
|
Tropical shelves |
8.6 |
310 |
2.2 |
0.671 |
3.3 |
|
Non-tropical-shelves |
18.4 |
310 |
1.6 |
0.706 |
3.5 |
|
Coastal/reef-systems |
2.0 |
890 |
8.0 |
2.51 |
2.5 |
|
Rivers and lakes |
2.0 |
290 |
4.3 |
n.a. |
3.0 |
|
Weighted means or total |
363.8 |
126 |
0.26 |
0.07 |
2.8 |
Biomass Productivity of Marine Habitats (from Gaia, an Atlas of Planet Management) (89L1) (in grams of carbon/ m3/ year)
|
Mangroves |
1215 * |
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Coral Reefs |
900 |
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Estuaries |
810 * |
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Salt Marshes |
300 * |
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Upwellings |
225 ** |
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Continental Shelf |
162 *** |
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Open ocean |
57 # |
* 2/3 of all commercially valuable fish species spend the first stage of their lives here (Ref. 15 of Ref. (93W1)).
** 0.1% of ocean area
*** 9.9% of ocean area
# The diffuseness is apparent here.
(To convert grams of carbon to grams of dry organic plant-matter multiply by a factor of about 2.2. The conversion for dry fish matter is not known but is probably similar. )
The FAO's estimate (03W2) of total sustainable (marine) production still refer to the figure of approximately 100 million tonnes/ year (99N4). This estimate is higher than the annual catches of 80-85 million tonnes of the 1990s because it assumes efficient utilization of the stocks in healthy ecosystems where critical habitats have been conserved. Moreover, this estimated potential yield includes large quantities of living marine resources that thus far have been little exploited. Of these the best known are krill, mesopelagic fish and oceanic squids. (All of these are very low trophic level species.) The assumption of "efficient utilization of fish stocks in healthy ecosystems" seems wildly optimistic at best as the data of this Chapter indicates. The assumption of "critical habitats being conserved" falls into the same category (See Section [H] in this Chapter.) Krill populations and harvests have dropped dramatically during the past few decades. (See elsewhere in this Chapter.)
Go to this Chapter's Table of Contents ~ Go to top of Section [B] ~
Section [C] ~ FISHING AT INCREASINGLY LOW TROPHIC LEVELS ~
A study by Pauley et al (98P1) examined the diets of 220 fish species and on that basis, gave each species a numerical trophic level ranking on the food web from 1 to 5 (1= plankton; 4.6= red snapper). Based on FAO data on fish landings worldwide it was found that the average ranking of the ocean fish catch has been declining for 45 years at a rate of about 0.1/ decade. Humans now eat somewhere between trophic levels 2.5 and 4.0 (98P1).
The most efficient fishing operation at present average 50 tons/ day under good conditions. The same efficiency applied to zooplankton would average much less than 0.5 ton/ day (81C1). If the fishing industry fished all the way down to the trophic level of zooplankton, fuel costs, labor costs and capital costs per ton of fish caught would increase by about a factor of 100. All this points up the non-sustainability of the practice of fishing at ever-lower trophic levels.
The types of fish being caught worldwide in commercial operations during the past 45 years have shifted down the food web. Long-living, highly nutritious fish such as snappers are being replaced by younger invertebrates and fish of lower nutritional value. This indicates that present exploitation patterns are non-sustainable (98K1).
There has been a shift in wild fish capture from large and valuable carnivorous species to smaller, less valuable species that feed at lower trophic levels (Ref. 9 of Ref. (00N1)).
As fish at the upper levels of the ocean food chain are over-fished, fishers tend to fish at lower trophic levels. Ultimately this trend must result in fishing at such low tropic levels that the fish species are so small and diluted that it is no longer economical to fish. At the current rate of descent, it will take 30-40 years to fish down to the level of plankton (98M8). There are data on the current ratio of fishing-boat fuel-consumption to fish harvests. (See elsewhere in this document or in "Fishery Degradation: A Global Perspective" on this website.)
Humans are now fishing not only in deeper waters, but also lower on the aquatic food chain. As these lower trophic levels of the ocean food chain decline, the chances of recovery of fish species nearer to the top of the food chain are diminished even further (98P1).
Current ocean fisheries yields have been maintained largely by development of formerly non-traditional species, e.g. copelin and sprat in the north Atlantic, and pollock in the north Pacific. Species in the future will likely be smaller in size and shorter-lived (81C1). i.e. of lower trophic level.
The fast-growing aquaculture industry needs so much fish oil from wild stocks of anchovy, herring, menhaden and other small bony fish of low trophic level, that in six years the supply will be unable to keep pace with the growth, according to global aquaculture and fish oil experts. Today, almost one-third of all the fish caught in the world are turned into fishmeal and oil. Now, penned (aquaculture) fish consumes 40% of the fishmeal - and more than 60% of fish oil. The oil gives farm fish key nutrients to grow and allows them to pass on heart-healthy omega-3 fatty acids to diners. In six years, if the aquaculture industry continues to grow at projected rates, aquaculture is expected to use up to 60% of the global supply of fishmeal and possibly 100% of the fish-oil supply, said Stuart Barlow, director-general of the London-based International Fishmeal and Fish Oil Organization (04D1). The bulk of the remainder of fishmeal and fish oil consumption is by farm livestock, so increasing the scale of aquaculture comes at the expense of (a) protein supplies from land-based livestock and (b) decreasing food supplies for high trophic levels of wild marine fish.
30% of the marine harvest consists of small, low-value fish like anchovies, menhaden, pilchard or sardines, many of which are reduced to fishmeal and used as protein supplements in feeds for livestock and aquaculture. Over time the fraction of the global catch made up by these low-value species has risen as harvests of high-value (high trophic level) species have declined. This trend partially masks the effects of over-fishing ((97F4), p. 5).
Go to this Chapter's Table of Contents ~ Go to top of Section [B] ~ Go to top of Section [C] ~
Section [D] ~ OVER-FISHING GENERALLY ~ [D1]~ All Trophic Levels, [D2]~ High Trophic-Level Fisheries, [D3]~ Low Trophic-Level Fisheries
Part [D1] ~ All Trophic Levels ~
World fish stocks have collapsed by nearly 33% and the rates of fishery decline are accelerating. In 2003, 29% of open sea fisheries had declined to less than 10% of their original yield. The global catch (marine?) fell by 13% between 1994 and 2003 ("50 Years of Fish...," BBC News (11/20/06)).
Sustainability of fishery outputs, however defined, rarely if ever occurred as a result of an explicit policy, but as a result of our inability to access a major portion of exploited stocks. With the development of industrial fishing, and the resulting invasion of the refuges previously provided by distance and depth, our interactions with fisheries resources have come to resemble the wars of extermination that newly arrived hunters conducted 40-50,000 years ago in Australia, and 12-13,000 years ago against large terrestrial mammals in North America (05P1).
Global (marine) catches began to decline in the late 1980s, a trend reversal due to broad-based collapse of the underlying ecosystems, long masked by systematic over-reporting by China and the targeting of deep water stocks (05P1). The peak catch rate was around 80 million tonnes per year (05P1).
The rate of decline in the (mean) trophic level of captured fish has mostly declined since the 1950s, with the strongest rate of decline in the 1980s. Fisheries were operating, on average, at a trophic level of 3.37 in the early 1950s; now their mean trophic level is about 3.29, but this was as low as 3.25 in 1983. So far humans do not normally eat zooplankton (trophic level 2), however there is now a market for jellyfish in East Asia. Some western countries have begun to export this product (05P1).
In 1950, no marine fish stocks were known to be over-fished (98K1).
Disappearance of fish stocks from an area can be predicted in advance according to Dr. Jan Lochner. About 12 years ago he predicted the collapse of South Africa's pilchard industry, although at that time there was no sign of collapse. Today South Africa's pilchard catch is only 10% of what it was then. He also predicted the collapse of California's pilchard industry. He predicts Namibia's anchovy industry faces the same collapse. His theory uses catch-data for a number of years, and the age at which fish reach sexual maturity. (When fish populations become too young to reproduce, they collapse.) (80F1).
Most published studies agree that the northern temperate areas of both the Atlantic and Pacific Oceans are being fished to their full potential. The total (potential?) increased yield from lightly exploited areas has been estimated at 30-50 million tons/ year. The potential for krill has been estimated by various authors at 25-100 million tonnes/ year ((81C1), p. 110). (Krill harvests are in a state of decline.)
Of the 280 fish stocks monitored by the FAO, 25 are considered slightly to moderately exploited, and 42 stocks are over-exploited or depleted (89L1).
Estimates of total sustainable (marine?) production still commonly refer to the figure of 100 million tonnes/ year (99N4). This is higher than the annual catches of 80-85 million tonnes of the 1990s because it assumes efficient utilization of fish stocks in healthy ecosystems where critical habitats (e.g. coral reefs, mangrove swamps, coastal estuaries) have been conserved. Moreover, this estimated potential yield includes large quantities of living marine resources that thus far have been little exploited. Of these the best known are krill, mesopelagic fish and oceanic squids (03W2).
25-30% of the world's fish populations are over-fished, while an added 40% are "fully exploited" (02D2).
Ratio of 1998 production and maximum historical production, by region (00F2) (03W2)
|
Antarctic |
0.14 |
|
Atlantic, SE |
0.39 |
|
Pacific, SE |
0.43 |
|
Atlantic, NW |
0.44 |
|
Atlantic, Western central |
0.71 |
|
Pacific, Eastern central |
0.73 |
|
Mediterranean/Black Seas |
0.81 |
|
Pacific, NE |
0.83 |
|
Atlantic, SW |
0.86 |
|
Atlantic, Eastern central |
0.87 |
|
Atlantic, NE |
0.92 |
|
Indian Ocean, Western |
0.94 |
|
Pacific, Central western |
1.00 |
|
Pacific, SW |
1.00 |
|
Pacific, Northwest |
1.00 |
|
Indian Ocean, East |
1.00 |
The species composition of the marine catch has changed. High-value species -bottom-dwelling species (demersal) and large surface-dwelling species (pelagics) - are gradually being substituted by shorter-lived pelagic and schooling fish. FAO studies indicate many causes for this shift. These include the thinning out of (over-fished) top predators; increases in natural production of small pelagics through nutrient enrichment of coastal areas, enclosed and semi-enclosed seas; and changes in fishing strategy and technology. The main force underlying such changes, however, is the change in harvesting costs as fishing technology has advanced and as various stocks have been depleted, and the impacts of these changing costs on operations (03W2).
During the 1980s, the number of overexploited (over-fished) species increased by a factor of 2.5 (02D5).
World-wide, 60-70% of (marine?) fish stocks require urgent intervention to control or reduce fishing to avoid further declines of fully exploited- and over-fished resources and to rebuild depleted fish stocks (FAO statement of 5/19/98). (The global fishing capacity needs to be reduced by at least 30% to rebuild over-fished oceans and farms. Marine fishery potential could reach 93 million tons/ year if resources were better managed - a gain of 10 million tons from the present potential (FAO estimate in a statement of 5/19/98).
An FAO assessment of the status of the 19 principal fisheries of the Northwestern Atlantic Ocean found 4 fisheries depleted and 9 others "fully exploited". This often means that yields are well below their biological maximum (Ref. 9 of (85B1)). The FAO estimates that all 17 of the world's major fishing areas have either reached or exceeded their natural limits, and 9 are in a state of serious decline (Ref. 25 of Ref. (94P2)) (Ref. 6, Chapter 5 of Ref. (94B3)).
According to the UNFAO, all 17 of the world's major fisheries are being fished at or beyond capacity: 9 fisheries are in a state of decline (94B4).
By 1989, all marine fisheries were being fished at or beyond sustainable yields. Of the world's 15 leading oceanic fisheries, 13 are in a state of decline (96B1). A common criterion for over-fishing is a fish population of less than half of the historic (pre-large-scale fishing) population.
The National Marine Fisheries Service (NMFS) found (in the mid-1990s) that 1/3 of 275 commercial fish stocks in US coastal waters were over-harvested, and nearly 50% were existing at population levels below what is needed to produce long-term sustainable yields. (97U1).
Some 11 of the world's 15 major fishing areas, and 69% of the world's major fish species, are in decline (98M1).
The UNFAO estimates that nearly 70% of the world's commercial fish species are fully exploited, over-fished, or otherwise in urgent need of management (98K1).
All but two of the world's 15 major marine fishing zones are at their limits, in decline or in recovery, and the majority of the world's near-shore fisheries are thought to be fully or over-exploited (Ref. 1 of Ref. (98W1)).
In the 20 years since EEZs were first established, over-fishing has increased (Ref. 51 of Ref. (98W1)). EEZs (Exclusive Economic Zones) were established to give nations "ownership" of the marine fish off their shores. The theory was that this would reduce over-fishing. One problem is that poorer nations cannot afford to protect their fish from marauding wealthy nations. Also people tend to "discount" future harvests of all kinds, even of resources that they own. Economists recommend discounting future harvests at a rate equal to interest rates on financial investments, which translates into a recommendation to wipe out the resource. (Deposit the extra money earned from resource depletion into a bank account. Then, when the resource has been wiped out, you live off the interest from that account.)
44% of the (marine?) fish stocks that the FAO assesses are intensely or fully exploited; 16% are over-fished; 6% are depleted, and 3% are slowly recovering. The eastern and western regions of the Indian Ocean are the only major fishing grounds that have still not apparently reached their limits. Coastal fisheries in the Indian Ocean, like coastal fisheries around the world, are largely fully exploited. Overall, the potential for new fisheries is small. While some new ones will be developed, the major fishing grounds like the Peruvian upwelling, the North Atlantic, and the North Pacific have already peaked (Ref. 26 of Ref. (98W1)).
The 9/97 National Marine Fisheries Service (NMFS) report to Congress "Status of Fisheries of the US" reveals that one third of marine fish species in the US that are known well enough to classify are classified as "over-fished". The report admits however that the status of many fish populations is unknown. (Only 38% of the 727 species under NMFS jurisdiction can even be classified.) According to the NMFS report, 21 Gulf Coast species are "over-fished" and the status of 63 Gulf Coast species is unknown. It is widely believed that many fisheries in the "unknown" category are depleted. (97D3).
The 9/97 National Marine Fisheries Service (NMFS) report to Congress "Status of Fisheries of the US" reveals that 96 marine fish species out of 279 species counted in the US that are known well enough to classify are "over-fished" or "heading that way" (97F7).
If fish stocks were allowed to recover, the FAO estimates that fishers could increase their sustainable catch by as much as 20 million tons/ year (94W2).
According to the UNFAO, about 70% of our global fisheries are now being fished close to, already at, or beyond their capacity (05O1).
FAO analysts found over-fishing in 1/3 of the fisheries they reviewed; they found some depleted fish populations in all coastal waters around the world (Ref. 34 of Ref. (94W2)).
Signs of over-fishing appeared by the 1970s. After increasing at nearly 6%/ year during 1950-70, growth in annual fish catch slowed to less than 1%/ year. In per-capita terms, growth of nearly 4%/ year during 1950-70 dropped to almost minus 1%/ year after 1970 (85B1).
FAO marine biologists believe the oceans cannot sustain a catch of over 100 million tons (tonnes?)/ year (93B1). It seems unlikely that the generally accepted potential of 100 million tonnes/ year of traditional marine species will be achieved on a sustained basis. It is more likely that the potential sustainable marine catch is nearer to the present-day catch of 60 million tonnes/ year (81C1).
During the period between the mid-1970s to mid-1980s, even new fisheries of the southeastern Pacific Ocean and New Zealand's coastal fisheries have been fished quickly to the point of collapse (85B1).
During the period between the mid-1970s to mid-1980s, even new fisheries of the Gulf of Thailand have quickly been fished to the point of collapse (85B1). Since 1970, the Gulf of Thailand has shown evidence of much over-fishing. Although the Gulf of Thailand was one of the Pacific Ocean's most productive fishing areas, in 1981 the catch there had diminished from 350 to 70 kg./ hour of trawler-effort (Ref. 2 of Ref. (87M1)).
Most Mediterranean native oyster beds are in such poor conditions that they are no longer able to support intensive culture (01B4) (07A1).
In the 18th and 19th centuries, large offshore oyster grounds in the southern portion of the North Sea and the English Channel produced up to 100 times more than today's 100-200 tonnes (99U4), (05B2) (07A1).
Although the global (marine?) fish catch is just below its estimated sustainable yield, fishermen exceed the estimated sustainable yield in 4 of 16 major fisheries: Pacific Northwest, the Mediterranean and Black Sea, the eastern Indian Ocean, and the southeast Pacific - and are close to it in many other areas (90B1). The UN FAO indicates that 4 of 17 of the world's fishing zones are over-fished (93B1).
In the US, 45% of the 156 fish populations for which assessments of resource status are available are classified as over-utilized (Ref. 10 of Ref. (93R1)).
Yields of 35% of the most important commercial fish stocks declined between 1950-94 ((96G1), p. 31).
The NMFS fall 1997 report to Congress stated that, in the coastal waters of the US, 86 species were over-fished, 183 species were not over-fished, 10 species were approaching an over-fished condition, and the status of 448 species was unknown (98C1).
US Stock Status Report. On 10/29/99, NMFS released its annual report to Congress on the status of US marine fish stocks, concluding that 98 species were over-fished. Changes since 1998 include 10 species removed but 18 species added, 5 species were approaching an over-fished condition (down from 10 species in 1998 as 5 species were moved to the over-fished category), 127 species were not over-fished (200 species in 1998) 79 species were moved to the "unknown" category because of more stringent information requirements). The status of 674 species (544 species in 1998) was unknown (99B1).
In October 1999 the NMFS (National Marine Fisheries Service) report to Congress, "Status of Fisheries of the US." listed 98 species as over-fished, 127 species as not over-fished, 5 species considered "approaching an over-fished condition" (00S1). For 674 fish species, 75%, the NMFS says it does not know whether or not they are over-fished. The accuracy of the science NMFS uses to assess whether or not a fish population is "over-fished" is questioned by environmentalists and commercial fish officials alike. As an example, they cite the NMFS's inability to identify a critically threatened fishery in its 1998 "Status of Fisheries of the US" report to Congress. A year later the Department of Commerce declared the Pacific groundfish industry a disaster. Yet in the 1998 report to Congress the vast majority of groundfish in the Pacific council's jurisdiction were identified as "not over-fished," "not approaching an over-fished condition," or "unknown" (00S1).
As of 1999, FAO reported that 75% of all fish stocks for which information is available are in urgent need of better management - 28% are either already depleted from past over-fishing or in imminent danger of depletion due to current over-harvesting, and 47% are being fished at their biological limit and therefore vulnerable to depletion if fishing intensity increases (00G1).
An FAO report says wild fish stocks are becoming severely depleted. "About 47% of the main stocks or species groups are fully exploited and are therefore producing catches that have reached, or are very close to, their maximum sustainable limits," (03W1).
For the 590 "stock" items for which FAO had some information, 149 were in an unknown state. Among the 441 for which data were available, 9% were depleted, 18% were over-fished, 41% recovering, 47% appeared fully exploited, 21% were moderately exploited, and 4% were classified as under-exploited, i.e. they could sustain catches higher than current levels (03W2).
About 25% of the world's major fisheries are currently over-fished and another 40% are estimated to be fully-fished. As a result of over-fishing and poor land use, freshwater fish are among the most highly threatened group of animals in the world. 20% are extinct, threatened or vulnerable. Commercially important fish such as the coral reef Napoleon wrasse, the Patagonian Toothfish, the Atlantic Toothfish, the basking shark and the whale shark could end up on the endangered list as well." (04V1).
Eight species are already listed in the most threatened category and a further 28 are listed as likely to be threatened if fishing is not brought under control (04V1).
The Myers/ Worm Study: Every single species of large wild fish has been caught so systematically over the past 50 years that 90% of each type have disappeared, according to the first scientific study to assess the fish left in the global ocean. And, from the tropics to the poles, those left in the sea are only one half to one fifth the size they were before industrialized fishing began in about 1950 (03M1). The study by marine biologists Ransom Myers of Dalhousie University in Halifax and Boris Worm of the Institute for Marine Science in Kiel, Germany, catalogues biological destruction that is unprecedented in its global scope and rapidity since the dinosaurs died out 65 million years ago (03M1). The study on fish reported in Nature took 10 years and examined all major fisheries in the world in 9 oceanic systems and on 4 continental shelves (03M1). (Continued in next paragraph)
A separate scientific study published 5/14/03 by the Species Survival Commission of the Swiss-based World Conservation Union warned that other ocean creatures are faring no better than the big fish. The phenomenon is driven by advances in the sonar methods developed during WWII and satellite methods of finding the ocean's warm fronts where fish once congregated (03M1).
Myers and Worm (03M4) reported that industrialized fishing commonly decreases the abundance of a fish community to 20% of its unfished level within the first 15 years of fishing. Falling to 50% of its unfinished level is usually considered the point at which steps need to be taken to stabilize the fishery.
Southeast Asia provides ample evidence of over-fishing: the increasing proportion of "trash fish" caught by trawlers in shallow waters; the high percentage of juveniles in net hauls, and the leveling-off or outright decline in catch volume of some countries. Demersal and semi-pelagic species of the west coast of peninsular Malaysia are fully exploited, showing a decrease in total landings and an increase of trash fish as a percentage of total catch (Ref. 1 of Ref. (87M1)).
During 1974-84, even new fisheries of the Indian Ocean have quickly been fished to the point of collapse (85B1).
Over-reporting by China has masked dramatic declines in global marine fish catches for more than a decade. The amount of seafood landed has actually been decreasing during the 1990s by nearly 800 million pounds/ year, rather than increasing by 700 million pounds/ year. The over-reporting has thrown off the global fisheries statistics that the Food and Agriculture Organization of the United Nations (UNFAO) compiles for use by all nations. (The FAO relies on voluntary reporting of catches from countries to estimate the amount of fish the oceans hold (01H1).) Using FAO statistics gathered since 1950, scientists created maps of world fisheries catches and built a computer model to predict catch size in different ocean regions. The model showed China's reported catches were unrealistically high when compared with catches from other ocean areas that have similar characteristics such as depth, temperature and biological productivity (01H1). Contrary to UNFAO statistics, which indicated that the global fisheries catch is stable, leading fisheries scientists reveal that marine catches have actually been declining for over a decade. This new evidence means that the true state of the oceans is far worse than anyone has previously realized. This is because of vast over-reporting by the People's Republic of China. Presently only a single institution, FAO, maintains global fisheries statistics. As a UN organization, FAO receives, but is not able to verify, statistics reported by member countries, even when they are suspected of being wrong (01U3). (continued below)
Over-reporting by China (Continued) Using FAO's catch data and a massive statistical analysis that compared the predicted fisheries against those reported, the authors showed errors in the official fishery statistics. These inflated statistics had led to complacency about the need to more effectively manage fisheries and have resulted in unwise investment decisions by banks and industry. Over the past 30 years there have been dramatic increases in the exploitation of world fisheries including more species being marketed and new fishing areas opening up. Increased effort and fishing pressures are devouring the accumulated "old growth" riches of the sea. Despite scientists' widespread expectations that annual catches of the world's fisheries would plateau at values of around 80 million tons, global catches reported by FAO generally increased through the 1990's - driven largely by inflated catch reports from China (01U3). (continued below)
Over-reporting by China: Many countries over and under-report their catch statistics, but none has as big an impact as China. Although Chinese waters covers only 1% of the world's water surface, China accounts for 40% of the deviation between reported and corrected. The study highlights anomalies in the 1990's of as much as 10 tonnes/ km2 when compared to reported amounts for Chinese waters. The same state entities devoted to monitoring the economy are also tasked with increasing its output. Studies showed that whatever political leaders set as production targets is what is officially reported. If political leaders dictate fisheries to increase by 5% then it is reported to increase by 5%." (01U3).
Before completion of Aswan High Dam in 1965, the Nile River carried 43 km3/ year of water to the sea. Since the dam, it has carried 3 km3/ year. As a result, fisheries of the eastern Mediterranean Sea have collapsed (90C2).
Of 47 species of fish harvested from the Nile River prior to the Aswan Dam, 17 were still being harvested a decade after the dam's completion (95P4).
The Nile River's fisheries have collapsed, as have Mediterranean Sea's sardine fisheries (96M1).
The Azov Sea fishery once yielded 200,000 tons of fish/ year. It is now closed (Ref. 51 of Ref. (94W2)).
In 1957 the Aral Sea fish catch was 50,000 tons/ year (95H1).
The Aral Sea, as recently as 1960, yielded 40,000 tonnes/ year of fish (93B1).
In 1993 the Aral Sea was essentially dead (93B1). Commercial fishing in the Aral Sea ceased by 1982 due to irrigation diversions that began in 1958. In 1994, 3000 tons of fish were caught in the Amu Darya delta of the Aral Sea (95H1).
Some 20 of the 24 fish species in the Aral Sea have disappeared (95P4). The 1950s fish catch in the Aral Sea of 44,000 tons/ year has dropped to zero (95P4), (96P1).
The commercial fish catch in Russia's Azov Sea dropped 97% between 1975 and 2000 (01G2).
According to National Research Council's 1996 Report on the Bering Sea Ecosystem, "It seems extremely unlikely that the productivity of the Bering Sea ecosystem can sustain current rates of human exploitation as well as the large populations of all marine mammals and birds that existed before human exploitation - especially modern exploitation - began" (98D1).
Fish catches in the northwest Atlantic have fallen 40% since the early 1970s (Ref. 20 of Ref. (98M7)).
The North Atlantic is so severely over-fished that it may completely collapse by 2010 according to a new study that includes the most comprehensive survey of the region so far. North Atlantic catches are down to half of what they were in 1950 despite a tripling of the fishing effort. The total number of fish has gone down even further. So-called "high quality table fish" have gone down over 80% since 1900. Normally falling catches would cause some fishers to go out of business and thus reduce the fleet, but the fleet is subsidized by government and thus kept artificially alive (02U2).
Namibia watched the catch in its zone (EEZ?) fall from nearly 2 million tons in 1980 to less than 0.1 million tons in 1990 (Ref. 16 of Ref. (93B1)).
The Gulf of Thailand's fish catch has dropped by over 80% since 1963 (98U9).
Southeast Atlantic fishers off the coasts of Namibia and South Africa have experienced more than a 50% decline in harvest since the early 1970s (98M1). (Ref. 20 of Ref. (98M7)).
Surveys off the west coast of Africa show that fish stocks in shallow inshore waters, where artisan fishers ply their trade, dropped by more than 50% from 1985-90 because of increased fishing by commercial trawlers ((95F2), p. 22).
Within European waters, 59% of 78 stocks have been classified as over-utilized (Ref. 10 of Ref. (93R1)).
Historical losses of Europe's wild native oyster reefs exceed 90% (97M4).
Total fish landings in European sea regions peaked at 12 million tonnes in 1997, but have decreased since then in terms of both quantity and quality, down to 7.6 million tonnes in 2002 (06E2) (07A1).
About 40% of US fish stocks are depleted or over-fished (02U3).
The number of fish stocks in need of stronger conservation in US coastal waters has increased for the fourth year running. The number of fish stocks in jeopardy jumped from 98 to a record high 107, according to a new (about 2/13/01) Department of Commerce 2000 Report to Congress: Status of Fisheries of the US. For more information about the report or MFCN: 202-543-5509 or www.conservefish.org. Full report: www.nmfs.noaa.gov/sfa/reports.html. Contact: Herb Ettel, Marine Fish Conservation Network, 202-543-5509.
The Magnuson-Stevens Act of 1976 created the first US management authority over fishing in waters from 3 miles to 200 miles offshore. The law ended over-fishing by foreign boats. But over-fishing by US boats continued, leading to declines in several fish species (00G2).
The North Atlantic has about one-sixth the number of fish it had in 1900 and is being fished 8 times as intensively, scientists say. Fishermen are also chasing species ever lower on the food chain as bigger fish are depleted. "With few exceptions, we are going to lose most fisheries in the next decade if we don't quickly mend our ways," said Daniel Pauly, a University of British Columbia scientist who headed the study. The group announced its results at the annual meeting of the American Association for the Advancement of Science (02D1).
At least 20% of all freshwater fish have become extinct, threatened, or endangered in recent years. (The number of known freshwater fish species exceeds 9000.) (95A1) (Ref. 2 of Ref. (96A1)).
"A mass extinction is occurring in our lakes and rivers," said Anthony Ricciardi of Dalhousie Univ. in Halifax. Common freshwater species - from snails to fish to amphibians - are dying out 5 times faster than terrestrial animals, 3 times faster than marine mammals, and at the same rate as rain forest species. 123 freshwater species have been lost since 1900, and hundreds are considered imperiled - Ricciardi predicts 4%/ decade. The affect of large dams on freshwater species has been disastrous, while the second leading cause of loss is due to invasion of non-native species. North America has 60% of all known crayfish, 1/3 of all freshwater mussels and three times more freshwater fish than all of Europe and the former Soviet Union (ENN (10/16/99)).
A 9/99 USGS report (a $1 million 1,000-page survey of America's biological resources) notes that almost 60% of California (marine and freshwater?) fish species are extinct or nearly extinct (Sacramento Bee (9/17/99)).
37% of all freshwater fish species are either threatened or already extinct (42% in Europe) (98B1).
In the Missouri River the commercial fish catch has fallen 83% over the past 50 years (Ref. 28 of Ref. (96A2)).
63% of California's native fish are extinct, endangered, threatened or declining (96A2).
Since 1908, the commercial fish catch in the Illinois River has fallen 98%. It once produced 10% of the US freshwater fish catch (96A2).
In Colombia, annual fish production in the Magdalena River has dropped from 72,000 to 23,000 tonnes in 15 years (98U10).
Part [D2] ~ High Trophic- Level Fisheries ~
Over-fishing led to one fishery after another in the 1990s being declared exhausted. After cod and haddock were fished out, fishermen began harvesting "trash fish" they used to throw away, such as spiny dogfish. Britain created a hot market for that white fish, using it in fish-and-chip dinners. Soon, however, those stocks also collapsed (02D1).
Several studies (03M4) (03C1) (01C2) estimate that the biomass of large predatory fish (e.g. swordfish, marlin and tuna) is 10-33% of the size it was before the industrialization of fishing before WWII.
Commercial harvests of rockfish in Chesapeake Bay: around 500 tons/ year around 1940, peaking at around 4000 tons/ year around 1970, and dropping to 500 tons/ year in 1983-4 (Chesapeake Bay Foundation Annual Report (1985)).
The catch of albacore tuna in the southern Pacific is expected to exceed the sustainable catch by 600% in 1989 (89L1).
The chum salmon fisheries have collapsed in Russia's Khor and Bukin Rivers (tributaries of the Usuri and Amur River Basins (Journal of Forestry, 92(12) (1994) p. 38).
On the west coast of North America, at least 106 major populations of salmon and steelhead have been wiped out (92R1).
In April of 1994, the Pacific Fishery Management Council banned salmon fishing off Washington State for the first time (Ref. 3, Chapter 5 of Ref. (94B3)).
From 1959-68, Newfoundland cod landings soared, reaching an all-time high of 810,000 tonnes in 1968, while estimates of harvestable biomass dropped by 82% from 1962-77, by which time the Grand Banks fishery was on the verge of commercial extinction. The stock never fully rebounded and rapidly declined under renewed pressure from the domestic Canadian offshore trawler fleet, leading to complete collapse and closure (in 1992) of the once-legendary fishery (98D1) (98G1).
The total harvest of groundfish (cod, haddock, flounder, etc.) in the New England fishery has fallen from 6 million tonnes/ year in the mid-1960s to 3 million tonnes/ year in the early 1970s to 2 million tonnes/ year in the mid-1980s to 1 million tonnes/ year in the mid-1990s (94A1).
In Canada, the cod population crashed so completely that an 8-year-long total ban on cod fishing has failed to bring it back (01C1).
Principle stocks of orange roughy (which started appearing in fish stores in the late 1980s) around New Zealand have collapsed (98P1).
In the last 50 years, the catch of popular fish species such as cod, tuna, and haddock has decreased by more than 50% despite a tripling in fishing intensity across the North Atlantic (02D1).
In the past 50 years, the prevalence of cod, tuna, groupers and sharks - the ocean's most valuable fish - is estimated to have fallen 90% (04V1).
The number of breeding-age adults of Atlantic bluefin tuna have dropped to 13% of their mid-1970s population. Despite this, the US, Canada and Japan have agreed to increase the catch quota from 2200 tons to 2354 tons (Pittsburgh Post Gazette (12/9/96)).
Atlantic stocks of bluefin tuna have been reduced by 94% (Ref. 8, Chapter 5 of Ref. (94B3)).
Populations of western Atlantic Ocean Bluefin tuna (Breeding adults, age 8+ years) (94P1) (Population data are in 1000s.):
|
Year |
1970 |
1975 |
1980 |
1985 |
1990 |
1991 |
|
Population |
225 |
185 |
85 |
45 |
30 |
25 |
The population of bluefin tuna that spawns in the Gulf of Mexico has dropped 90% since 1975. The population of bluefin tuna that spawns in the Mediterranean Sea has declined 50% since 1975 (Ref. 117 of Ref. (94W2)).
Ships using traditional fishing methods saw their catch of albacore tuna drop from 20,000 tonnes/ year in the late 1970s to 1750 tonnes in 1989 (in the north Pacific??) (90C1).
Salmon catches in the entire North Atlantic Ocean fell by more than 80% between 1970 and 2000. Today they stand at the lowest levels in known history (01W1).
The collapse of wild Atlantic salmon populations has accelerated throughout their Atlantic basin range. Historically, Atlantic salmon numbers were 2.5-5.0 million. Numbers dropped to 800,000 by the 1970s, 125,000 in 1996, and 80,000 in 1998 (New York Times (9/14/99)). When the population drops below 50% of the historical population a danger to long-term viability is usually seen.
In 1999, scientists sampled 32 rivers in Wester Ross and Lochaber (Scotland) that had been tested 10 years before. They found salmon had become extinct or were in danger of becoming extinct in 43% of these rivers (02M3).
Pacific salmon have disappeared from about 40% of their breeding range in Washington, Oregon, Idaho and California (98S1). More than 300 distinct salmon populations there are at risk of extinction (98S1).
California's salmon and steelhead populations have fallen by 80% (Ref. 19 of Ref. (96P1)).
Idaho's Coho salmon (one of Idaho's 5 salmon species) went extinct in 1986 (95A1), (96A1).
In the Pacific Northwest, Coho salmon are extinct in 55% of its range, and declining in 39% (96A1).
Spring and summer Chinook salmon are extinct in 63% of their range, and declining in 31% (96A1).
The Chinook salmon population in the Sacramento River dropped from 118,000 to 191 over the past two decades (93M3).
Runs of adult salmon and steelhead on Columbia River have declined from a historic high of 16 million fish to 1.5 million fish in 1992 (94B1). Salmon/ steelhead caught in the Columbia River by commercial fishermen: 21,100 tons in 1884; 600 tons in 1994 (96A2). In 1880, 19,500 tons of salmon and steelhead were harvested from the Columbia River (WA). In 1980 the harvest was 50 tons (96A1).
The commercial salmon catch in the Columbia River is plotted vs. time (1866-1994) in Fig. 5 of Ref. (96A2) (around 17,500 tons/ year during 1880-1930; around 2,500 tons/ year after 1980).
In Canada's Fraser and Skeena Rivers, Coho salmon is extinct in 55% of its range, and declining in 39% (causes: overfishing, logging, mining) (Ref. 110 of Ref. (96A2)).
100 years ago, 150,000 salmon were caught annually in the Netherlands and Germany. By 1920, the catch had dropped to fewer than 30,000, and by 1958 it completely disappeared (96A1).
Salmon caught in the Rhine River (Germany and Holland): 150,000/ year around 1896; 0 by the end of the 1950s (96A2).
Coho salmon along much of the Pacific Coast numbered 1.4 million in the 19th century and 39,000 in 1995, with much of the decline in the past decade (95M4).
Wild Atlantic salmon have disappeared completely from at least 309 river systems in Europe and North America according to a study released by World Wildlife Fund. The Status of Wild Atlantic Salmon - A River-by-River Assessment, reports that, in the 2005 rivers historically nurturing this species on both sides of the Atlantic, the wild fish have disappeared in Germany, Switzerland, the Netherlands, Belgium, the Czech Republic and Slovakia. And the species is on the brink of extinction in Estonia, Portugal, Poland, the US, and parts of Canada. Nearly 90% of the known healthy populations exist in only four countries: Norway, Iceland, Ireland, and Scotland. In the remainder of the range, 85% of wild Atlantic salmon populations are categorized as vulnerable, endangered, or critical (01W1).
In the Iranian Sefid Rud River delta in the southern Caspian, the commercial catch of sturgeon dropped from 6,700 tons in 1961 to fewer than 0.5 ton in 1993 (95P1).
Massive poaching and over-fishing were responsible for a drop in the adult sturgeon population in the Caspian Sea from 142 million in 1978 to 43.5 million in 1994 (David Filipov, Pittsburgh Post Gazette (6/15/97)).
The US accounts for 30% of the world's caviar market. The US Fish and Wildlife Service believes that 50% of the Caspian Sea caviar trade to be illegal. The US once led the world in sturgeon and caviar production, but by 1910 sturgeon in the US was nearly extinct (US FWS news release (3/25/98)).
Part [D3] ~ Low Trophic-Level Fisheries ~
Warmer temperatures and disappearing sea ice could threaten Antarctic whales, seals and penguins. Warmer temperatures and disappearing sea ice have resulted in an 80% drop in Antarctic krill, which is a major source of food for animals in the Antarctic. Krill feed on algae under the ice but warmer temperatures over the last 50 years have meant less ice and fewer krill. The most important finding was that there was a direct link between sea ice duration and extent and krill abundance. The krill population is only a fifth of that in the mid-70s. Krill feed on phytoplankton and algae and are eaten by fish, squid, sea birds, whales, some seals and penguins. The latest figures are from data between 1926-2003 gathered by nine countries. Results showed the krill population is concentrated northeast of the Antarctic Peninsula, but also revealed the long-term declines in krill stocks that can affect commercial fishing since krill are consumed by species for human consumption (04U1).
"Antarctic krill remains the largest exploitable stock and its exploitation also poses the greatest threat to the Antarctic ecosystem. Rapid growth in fish farming and the biotechnology industries are two key threats to sustainable harvests of krill. Fish farming is expanding at a rate of 11%/ year. In a decade, output is expected to exceed catches from ocean fisheries, and to overtake global beef production within 20 years (03O1). It seems likely that production of carnivorous farm-fish will be limited by harvests of menhaden and other small bony fish.
Key components of the marine food chain, plankton and krill, may be breaking down due to the hole in the ozone layer over Antarctica. The population of krill, which eat plankton and are a food staple for whales and penguins, is now "a quarter" of its population in the mid-1980s (Japan's Asahi Shimbum (1/2/00)). (Note: Other data indicate that at least the larger breeds of penguins prefer small fish and squid.)
In Antarctica, thinning of the ozone layer may account for the "dramatic" decline of a key marine species. Krill (food for whales) population off the Antarctic Peninsula, south of Tierra del Fuego, is 25% of what it was in the mid-1980s. More of the sun's ultraviolet radiation is reaching the Earth's surface, killing plankton on which krill feed (Tokyo Asahi Shimbun (1/2/00)).
The southern stock of the South African pilchard, despite various restrictions by the South African government, has declined drastically since 1968, and now yields only 40,000 tons/ year instead of the potential maximum of 150-300,000 tons/ year (77P1).
Chesapeake Bay's oyster catch peaked in the 1880s, but the last few years have shown the lowest harvests on record - about 10% of the peak. Declining water-quality and over-fishing are considered as primary factors in this decline (Chesapeake Bay Foundation Annual Report (1985)).
In the Gulf of Gabes, one of the Mediterranean Sea's most important natural fisheries, the fish catch dropped from 36,000 tons in 1988 to 28,000 tons in 1992. The sardine catch there dropped by 2/3 (93H1).
Sardine harvests in the eastern Mediterranean Sea dropped 83% after the Aswan Dam was completed (95P4), (96P1).
Total collapse of pollock stocks in areas adjacent to the Eastern Bering Sea stock has already occurred from over-fishing. The remaining fishery is now compressed into significantly smaller areas and shorter seasons, placing increased pressure on remaining stocks. The Aleutian Island Region was closed to fishing in 1992, and is no longer capable of sustaining commercial fisheries. The Central Bering Sea-Bogoslof Island (the "Donut Hole") was closed to fishing in 1993 and has still not recovered (MFCN data of around 2002).
Pollock harvests account for 25% of the total catch off US shores. The value of the fishery: $650- $1000 million/ year. By 1998 the pollock population had declined to 50% of its population in 1988. However harvests have remained constant at close to 1million tons/ year (MFCN data of around 2002).
The Aleutian Basin population of Pollock straddles the offshore area controlled by the US and Russia, but Pollock congregate in a 142,000 km2 area ("Donut Hole"), an enclave of international waters ringed by EEZs of the two countries. The population collapsed due to over-fishing by China, Japan, South Korea and Poland. The overall Donut Hole catch was 363,000 tonnes in 1985, one million tonnes in 1989, and 300,000 tonnes in 1991 (94P1). The central Bering Sea catch of Alaska (walleye) Pollock dropped from 1.5 million tonnes in 1989 to 11,000 tonnes in 1992 due to over-fishing (95P1).
In 1989 the Bering Sea pollock fishery was open year-round. In 1991, the season was reduced to 148 days. By 1994, the factory trawl season declined only 70 days. In 1997 factory trawlers fished 55 days (98D1).
The massive "Donut Hole" fishery conducted by foreign factory trawlers in the Central Bering Sea (1987-92) virtually wiped out the large pollock aggregations in that region (98D1). The related Bogoslof pollock roe fishery (1987-92) was dominated by domestic factory trawlers, but it too collapsed and the stock continues to decline today (98D1).
The Chesapeake Bay oyster catch was 20,000 tons/ year in the 1950s, and less than 3000 tons/ year in the late 1980s (Ref. 21 of Ref. (94W1)).
Populations of American Oysters in Chesapeake Bay have dropped by 99% since 1870 (92R1).
The Chesapeake Bay yielded 8 million bushels/ year of oysters in the late 19th century. Now it produces scarcely 1.0 million bushels/ year (93B1).
Chesapeake Bay's hickory shad catch has declined 96%, alewife and blueback 92%, stripped bass 70%, American shad 66%, and oysters 96% from their historical peaks (Ref. 50 of Ref. (94W2)).
Chesapeake Bay's oyster catch is plotted vs. time (1900-83) in Ref. (85B1). The catch has declined 96% from its historical peak (Ref. 50 of Ref. (94W2)).
The white abalone (a mollusk) catch in California peaked in 1972 at 65 tonnes. It fell to less than 1.0 tonne in 1979 and remained at that level until 1995 when harvesting of white abalone was banned entirely (San Francisco Chronicle (7/7/98)).
The North Pacific crab industry has collapsed. An 80% catch reduction has been imposed (00S1).
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Section E ~ EXCESS FISHING CAPACITY ~
Threats posed by excess fishing capacity to the world's fish stocks have been acknowledged in major international agreements, including the UN Agreement on the Conservation and Management of Highly Migratory Fish Stocks and Straddling Fish Stocks and the FAO Code for Responsible Fishing (98D1).
The NMFS (National Marine Fisheries Service - a US government agency) has had no leadership under any administration or party. Since the 1970s all they have set out to do is build up the US fishing fleet only to buy it back because of over capitalization without any idea of how much fish is out there. We need a substantial turn around in our resource, but Congress is just listening to the large trawler organizations, seafood processors, and National Fishing Institute representing their short-term financial needs (00S1).
On the west coast of India in the fishery off the coast of Goa, the mechanized fishing fleet increased from 10 boats in 1964 to 2200 in 1998. The annual catch grew from 17,000 to 95,000 tons - well beyond sustained yield (71,000 tons) (00N3).
As the US halibut fishing fleet expanded to 5500 boats, the season was reduced to 2 days/ year. As a result, fishers employ the quickest, most hazardous methods. The results: fatalities, sinkings, and enormous amounts of spoiled fish, while consumers virtually never see fresh halibut. To reach the point at which all halibut boats could profitably fish throughout the year, 95% of the boats would have to leave that fishery (94S1).
In 1998, the world's large-scale fishing fleet has at least 50% more capacity than justified by the size of the world's fishery resources (Ref. 68 of Ref. (98M7)).
Today's world fishing industry has about twice the fishing capacity needed to bring in the sustainable yield of fish (Ref. 2 of Ref. (98W1)). During 1970-90, the FAO recorded a doubling of the world's fishing fleet (from 585,000 to 1.2 million large boats, and from 13.5 million to 25.5 million gross registered tons) (94W2).
Estimates for the world's commercial fishing fleet range upward of 3.5-4.0 million boats (02D2).
By the late 1980s, the world's large-scale fishing fleet had exceeded the maximum sustainable yield of all the world's commercial fish stocks by 30% (Ref. 67 of Ref. (98M7)).
During the 1970s and 1980s, the gross registered tonnage of the world's fishing fleet increased by 90%, while the technical capabilities of the world fishing fleet as a whole increased by 330% (Ref. 66 of Ref. (98M7)).
It is not just that there are more boats: sophisticated technology also makes fish easier to catch. Countries spend $2.5 billion in taxpayer's money each year to "search out the last fish left," in the North Atlantic (02D1).
The UNFAO says that even though 11 of the world's 15 main fishing grounds are seriously depleted, expansion of the global fishing fleet continues, with Southeast Asian nations and China being among the most aggressive (97F2).
The world's current fishing fleet catches 155% more fish than can be replaced through normal reproduction (98P2). This probably refers to the marine fleet only.
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Section [F] ~ POLITICAL ISSUES THREATENING FISHERY SUSTAINABILITY ~
Mexican fishing boats catch tuna "on dolphin", using nets that encircle both dolphins and the mature yellowfin tuna that swim under them. In the US, tuna caught in this way are banned. But in 1991 GATT found this blockage of tuna imports inappropriate (93F1).
The US National Marine Fisheries Service (NMFS) is buried in the Commerce Department that largely deals with manufactured commodities. No Secretary of Commerce has ever had a background in natural resource issues (94S1).
The US government has abdicated far too much authority to regional fishery councils dominated by fishing interests. No other natural resource - not timber, not minerals, not grazing lands - is as heavily managed by the very people who extract that resource. Too often, regional councils concentrated on dividing up the ocean-resource pie among competing fishing interests and ignored the fact that the pie was shrinking (02C1). Fishery councils ignored scientific warnings issued as early as 1984. Instead, a stubborn pro-industry bias drove managers to require absolute proof of a collapse before restricting fishing. Such proof is now available for west coast fisheries, but it's too late to avert a crisis (02C1). Absurdly, Congress has been considering a major rollback of federal fisheries law in a last-ditch attempt to continue excessive fishing levels, even in the face of a fishery collapse. In July of 2002, the House Resources Committee voted on rolling back the protections provided in the Magnuson-Stevens Act, a good law designed to conserve and manage fisheries that would have prevented this crash had the Act been implemented properly (02C1).
A national fish conservation coalition is charging that the Commerce Department's latest appointments to regional fishery management councils will harm fish more then help them by "continuing a pattern of mandating conflict of interest" which is "a key factor contributing to the drastic depletion of many US fish populations." Criticizing the new appointments announced 6/27/03, Lee Crockett, executive director of the Marine Fish Conservation Network (Network), points out that the newest appointees were 47.8% commercial fishermen, 35.2% recreational fishermen, and 16.9% others. Crockett, a marine biologist, cites a previous study showing the continuing pattern of appointing council members who have a direct interest in short-term profit, not long-term protection of the fish populations. "The councils were designed to facilitate catching fish, unfortunately that very design makes them poorly suited for fish conservation," Crockett said. Under the current system, state governors nominate individuals to be considered for membership on the regional councils, and the Secretary of Commerce selects members from the governors' suggestions. (Continued)
The study Crockett cites - written by Thomas Okey and published in the May 2003, edition of Marine Policy - found that between 1990 and 2001, commercial and recreational fishermen accounted for 82% of all the people appointed to regional fishery councils. The Okey study analyzed the makeup of the councils nationally over a 12-year period, and found a parallel between industry dominance of the council process and bad management decisions. According to the report's abstract, "Contemporary economic sensibilities within this "industry captured" regulatory process generate perverse incentives for management decisions that conflict with, and can undermine, national sustainability goals and standards, even when those standards are logically sound and agreed to by consensus." Report author Thomas Okey: "The skewed composition of the Fishery Management Councils appears to be a central reason for the mismanagement of our fisheries. Congress intentionally created a council system in which industry would dominate because they recognized the critical role of fishermen in making and complying with management decisions. Unfortunately, the institutionalized capture of resource decision-making by fishing industries promotes a pathological focus on short-term economic gains that consistently jeopardizes the long-term health of fish stocks and marine ecosystems." (Continued below)
The Network has documented that this continued pattern of special interest appointments has cost US taxpayers hundreds of millions of dollars in buyouts and relief programs as the industry dominated councils have repeatedly placed exploitation of the resource over conservation. For more information on the cost of mismanagement, visit http://www.conservefish.org/site/mediacenter/cost.pdf The Network cited the collapse of groundfish populations in New England and rockfish populations in the Pacific as "two of the most well known examples of what happens when a council refuses to make the hard decisions necessary to conserve fish populations for future generations." (03M5).
When Congress invented the fishery management councils as part of the NMFS there were (03E1):
No nation other than the US gives its fishing industry as much authority to make large-scale decisions about fishery conservation and management as the 8 regional fishery management councils in the US enjoy. In most countries, fishermen play important but advisory roles.
Australia's Fisheries Management and Administration Act of 1991 created a council system similar to that in the US, with council members predominantly composed of fishing industry members. The results have been similar to those in the US: In 1992 the Australian government classified 25% of known fishery stocks as over-fished. In 2003 it reported that 50% of the known stocks are over-fished (03E1). (Continued below.)
The Magnusen-Stevens Act requires that the optimum yield of a fishery cannot exceed the "maximum sustainable yield" (MSY) of the fishery. Theories developed by fishery science hold that a fish stock will produce its MSY when the fish population is between 40-60% of its pre-fishing levels (63 Federal Register 24212 (1998)).
The US lacks even basic information about a number of important fishery stocks. There are 932 fish stocks under federal management in the US EEZ, but the NMFS has information sufficient to evaluate the full status of about 25% of them, slightly more than 230. OF the nearly 700 stocks of "unknown" status, 99 are "major stocks" (defined as stocks with annual landings of more than 200,000 pounds). 9 of the 30 most valuable domestic fisheries are of "unknown" status. Thus the NMFS does not know whether the two most valuable fisheries managed by the councils - pollock and brown shrimp - are over-fished or not (03N1).
Of the 237 known stocks for which there is sufficient information to evaluate current stock levels, NMFS classifies 36% (86 stocks) as "over-fished". Of the 274 stocks for which it can be determined whether over-fishing is occurring, 25% (66 stocks) are experiencing over-fishing. 48 stocks (about 20% of known stocks) are both over-fished and experiencing over-fishing. This suggests that effective rebuilding plans either have not been implemented or have not taken effect. 27% of major US fishery stocks are over-fished, while 24% are subject to over-fishing (03N1). (Continued below)
According to the UNFAO, of the worldwide fish stocks for which information is available, 28% are over-fished, compared with 37% of all major and minor fisheries managed by regional councils in the US (02F1). What is odd about this is that fishery scientists in the US, particularly those in the NMFS enjoy a reputation as some of the most sophisticated and accomplished fisheries science experts in the world. Given the ability of these scientists, one would expect that the US fisheries management record would be better, certainly not worse, than the worldwide record.
More than 60% of the US fishery stocks that are currently under fishery management council rebuilding plans are still experiencing over-fishing. This suggests that the US fishery management councils have not yet adequately addressed the problem of too much fishing that led to the fisheries becoming over-fished in the first place. This suggests that the Councils' rebuilding plans are unlikely to be successful (02F1).
Since 1985, the percentage of US fishery council members who directly work in, or represent, the fishing industry has ranged as high as 88%, never dropping below 78%. (Continued below.)
The most frequently made criticisms of the 8 US fishery management councils under the NMFS are that (03E1):
A common link between over-fishing and over-grazing (03E1):
Like the Magnuson-Stevens Act (MSA) to deal with fishery management, the Taylor Grazing Act (TGA) was also enacted to bring previously unregulated areas under federal management and to promote conservation. Like fisheries in 1976, rangelands in 1935 were also in very poor condition. By 1935 only 16% of federal rangelands were in "excellent" or "good" condition while nearly 40% were in "poor" condition. The TGA , like the MSA, contained vague conservation standards, e.g. the TGA required the Department of the Interior to "stop injury to public grazing lands by preventing overgrazing and soil deterioration." "Grazing Advisory Boards" were created in 1939, quite comparable to Fishery Management Councils. These grazing boards included only stockmen, just as Fishery Management Councils contained almost entirely fishermen. The effects of the Grazing Advisory Boards were similar to those of the Fishery Management Councils, e.g. in 1936 only 16% of federal grazing lands were in "excellent" or "good" condition. In 1975 the figure was 17%. Conditions improved when, in 1976, the Grazing Advisory Boards were subject to the Federal Land Policy and Management Act. By 1984 more than 36% of federal grazing lands were in "excellent" or "good" condition. In 1994 "Resource Advisory Councils" replaced Grazing Advisory Boards with 2/3 of the Council members required to be representation from environmental, archeological, cultural, state and local government, public-at-large and academic interests. This change in makeup never really happened. The result was that the 36% of federal grazing lands in "excellent" or "good" condition in 1984 became 34% in 2001 (03E1).
It had long been possible to value a fishery by the amount the standing stock would be worth of sold on open markets. Such analyses -totaling up the poundage of a fishery resource and estimating its net worth -almost always concluded that the best economic strategy would be to sell off the entire resource all at once, and bank the proceeds, letting the cash equivalent of the resource grow monetarily (73C1) (02P2). The same basic type of "discount economics" invariably recommends against soil conservation - instead, put the money saved in a bank, so that when there is no more soil mankind simply lives off the interest in the bank account. (Continued below).
Under this economic model of the value of species, conservation of any population for future use is discouraged (97P3) (02P2). In the past decade, however, many environmental economists have pointed out another way to treat the question. They have argued that ecosystems perform important services to local and global economies that, if they had to be replaced by technology, would be very costly (97D2) (02D4) (02P2). Thus, an important value of an ecosystem is the replacement value of the services it provides for free. Marine ecosystems provide many such services, including capture of sediments by wetlands, protection from coastal storm damage by reefs or mangroves, production of oxygen and sequestration of carbon dioxide (99C5). Such analyses suggest that the costs of replacing the values provided by open oceans and coastal ecosystems total in the trillions of dollars (97C2).
The American fish harvesting industry is going broke nationwide due to over-fishing, loss of fish habitat, over capitalization, and government mismanagement, commercial fishing organizations and environmentalists agree. Government agencies responsible for the fishing industry say they cannot prove it is not already financially insolvent. "Most of the US fisheries stocks are facing a disaster due to over-capitalization of the fishing industry and the mismanagement practices of US Department of Commerce's National Marine Fisheries Service (NMFS) and their appointed regional fishery management councils," says Zeke Grader Jr., executive director of the Pacific Coast Federation of Fishermen's Associations, the largest active trade association of commercial fishermen on the west coast of the US (00S1).
The American fishing industry is a $25 billion wholesale business employs 300,000 people, and had over $3 billion in landing revenues for 1998, according to US Department of Commerce figures. But the Commerce Department is unable to say if the harvesting industry is broke because the Magnuson-Stevens Act provides confidentiality for financial disclosures by vessel operators and processing businesses (00S1).
"We are very close to total closure in most of our fisheries industries because we have an industry reliant on a national resource going to hell under the management of biologists and bureaucrats operating without a long-term business plan. The fish harvesting industry in the US isn't run like a business, and you can't prove the US fish harvesting industry is financially solvent," (00S1).
"Wall Street and US commodities analysts say there is no public investment in the fish industry with the exception of shrimp due to the volatility in fish stocks and lack of financial transparency of operation (00S1).
The financial data that is made available to the public by the government shows the fishing industry in distress and near collapse. In January, 2000, Commerce Secretary William Daley declared the west coast ground-fishing industry a disaster with loses of $11 million in revenues (00S1).
In Atlantic Canada, a nearly $2-billion, 5-year "social-adjustment" program (the "Atlantic Groundfish Strategy") helps fishers stay out of debt (Critics see it as a massive social-welfare program.) (98M1).
Collapse of the cod fishery in Canada's maritime provinces in the early 1990s left 30,000 fishers dependent on government welfare payments and decimated the economies of 700 communities in Newfoundland alone (99M4).
Many of the tuna farms operating in the Mediterranean are subsidized by payments under the European Union's Common Fisheries Policy (02R2).
In 1996, the EU paid $229 million (43% of the annual fisheries restructuring budget) for access agreements with Africa, and the fishers themselves paid only a small fraction of the cost (98M1).
The Norwegian sealing industry is not economically viable on its own terms, and is dependent on government subsidy (99H1).
The US Dept. of Commerce announced $5 million in added relief for New England fishermen in early 6/99. The money will be used to compensate inshore vessels that could not fish in closed areas between February and June of 1999. The New England congressional delegation assisted the region's fishermen in getting money in response to demonstrations and hardships engendered by closures. NMFS has not backed down or revised the rule limiting cod catches to 30 pounds/ day, which sparked many of the protests (Seafood.com (6/11/99)).
Fishing industry subsidies in 1998 included a $97 million dollar bail-out of two factory trawler companies: Tyson ($5 million) and American Seafoods ($92 million) (Niaz Dorry (niazd@dialb.greenpeace.org) (7/21/99)).
Various tax- and financing incentives encouraged US entrepreneurs to expand to take advantage of the expulsion of foreign competitors from the US EEZ (98G2).
In 1996 the Government pledged $25 million to buy out part of the commercial ground-fish fleet in New England (98M1).
Government policy during the 1970s and 1980s offered tax credits and loan guarantees to expand the US commercial fleet (97C1).
US taxpayers have spent $160 million since 1994 (on federal disaster relief for the fishing industry and fishers) without much benefit. Congress is being asked to appropriate another $421 million in federal disaster relief for the thousands of fishermen affected by the recent crab, salmon and groundfish stock collapses (00U1).
Since 1994, US taxpayers have paid more than $160 million to mitigate economic and ecological impacts of fishery management failures in New England, Alaska, and the West Coast, the MFCN report "Lost at Sea" found (00S1).
In 1995, Congress created a program to buy up commercial fishing permits and vessels in areas where the fish population was in decline from environmental factors and over-fishing. Sounds simple enough: Fewer fishermen catch fewer fish. But when the GAO took a look, it found much of the $140 million used to pay some people not to fish didn't stop other people from catching the same fish. In the New England program, where federal funds bought up fishing permits and ships, the GAO found that the effort stopped 79 vessels from fishing. But 62 previously inactive vessels that already had permits took their place (00U3).
The GAO also found that some fishermen used money from the program to upgrade other ships they already owned so they could land more fish. Others simply took the money and then switched to catching lobster, despite the fact that the lobster fishery is having similar problems (00U3).
Could Congress have known things would end up this way? Only if it had bothered to check decades of evidence. In 1999, a congressionally mandated study summarized the results of several salmon buy-back programs from the 1970s this way: "The programs had little effect on fishing capacity. Many of the retired vessels were marginal. Because many fishermen held more than one license, funds frequently were used to upgrade other vessels." A 1997 Canadian study found the same thing (00U3).
In 1998, the US government spent $20 million to buy back 9 factory trawlers to reduce pressure on dwindling stocks of Bering Sea pollock (ENS (3/10/00)).
Congress will soon be considering another $421 million in federal disaster relief for thousands of US fishermen hurt by recent crab, salmon and ground-fish stock collapses in New England, Alaska and along the West Coast (ENS, 3/10/00).
In March 2002, the National Marine Fisheries Service spent $10 million buying groundfish permits from New England fisherman, and a similar idea has been discussed for the West Coast (02D2).
Government financial assistance to aquaculture in the US in 1994 was over $60 million (97G1).
Bluefin tuna "farming" has emerged, with the Spanish as the European leaders. The tuna are captured live, placed in cages off the coast of Murcia in southern Spain. Bluefin tuna farming is increasing pressure on smaller fish species, such as anchovies and sardinella, which are sold to the farms to feed the tuna. Bluefin tuna stocks are over-exploited. A predicted collapse is possible in the near future. The European Union (EU) could take action to stop over-fishing of bluefin tuna and regulate its farming, but is being lobbied heavily to support the industry (02R2).
Go to this Chapter's Table of Contents ~ Go to top of Section [B] ~ Go to top of Section [C] ~ Go to top of Section [D] ~ Go to top of Section [E] ~ Go to top of Section [F] ~
Section [G] ~ FISHERY MANAGEMENT PROBLEMS FACED BY DEVELOPING NATIONS THAT THREATEN FISHERY SUSTAINABILITY ~
Developing countries do not have the resources to enforce the international agreements and fishery laws within their own boundaries (98K1).
In early 2005, local subsistence fishermen in the Philippines protested the loss of their traditional access rights that their government sold to foreign vessels (05O1).
Fishing off Somalia's coastline, the longest in Africa, proceeds largely untouched by government regulation ("Somalia's struggles", Pittsburgh Post Gazette (2/26/05) p. A-14.) This means that the rest of the world can regard Somalia's fish as free for the taking.
Nearly 40% of all fishery production is now internationally traded. Around 80% of fish for human consumption ends up in three main markets (Japan, the US and the EU) (03W2). Fisheries are the most globalized food industry: over 75% of the world's marine fisheries catch (over 80 million tons/ year) is sold on international markets (01U3).
Until 1988 European Community countries were self-sufficient in fish and shellfish; now they are net importers (93K1).
US seafood prices, especially for lobsters and shrimp, have increased 20-fold since 1950 (02D1). New Englanders can continue to eat their favorite fish because much of the seafood is imported from developing countries, a practice that the scientists said should not be allowed to continue (02D1). In essence, developed world consumers, who earn factors of 10 more than those of the developing world simply outbid developing world consumers for fish.
In 1996 the EU signed a $70 million/ year fisheries access-for-trade agreement with Mauritania. The agreement stipulated a 45% jump in number of boats and a 140% increase in allowable catch, despite the fact that Mauritania's fisheries are already fully exploited and some species are overexploited (Ref. 97 of Ref. (98M7)).
Go to this Chapter's Table of Contents ~ Go to top of Section [B] ~ Go to top of Section [C] ~ Go to top of Section [D] ~ Go to top of Section [E] ~ Go to top of Section [F] ~ Go to top of Section [G] ~
Section [H] ~ DEGRADATION AND SUSTAINABILITY OF ESSENTIAL FISH HABITATS ~ [H1]~ General, [H2]~ Mangrove Swamps, [H3]~ Reefs, [H4]~ Coastal Estuaries, [H5]~ Continental Shelves
Part [H1] ~ General ~
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, Chapter 5 of Ref. (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 industrial-, agricultural- or urban runoff, or starved of nutrients by dams (Ref. 55 of Ref. (98W1)).
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 nearly 20,000 square miles of Australian seagrass beds that contain "half the world's estimated 70 species" of seagrasses (Reuters (3/27/00)). Seagrass beds are prime breeding grounds for many fisheries.
Part [H2] ~ Mangroves ~
It is estimated that over 50% of the world's mangroves have been destroyed and they continue to decline at an alarming rate. Shrimp aquaculture development has been a major cause of recent mangrove loss, and it has been estimated that shrimp aquaculture may have been responsible for as much as 38% of global loss of mangroves. Destruction of mangroves leaves coastal areas exposed to erosion, flooding and storm damage, alters natural drainage patterns, increases salt intrusion and removes critical habitats for many aquatic and terrestrial species, with serious implications for biodiversity, conservation and food security. Carnauba forests provide an important economic resource for rural communities, providing them with materials for the production of wax, straw and other saleable products. Shrimp farming is worth US$6.9 billion at the farm gate and US$50-60 billion at the point of retail. Shrimp are farmed in about 50 countries - 99% of farmed production is from developing countries. Leading shrimp producers in 2000 were Thailand, China, Indonesia, India, Vietnam, Ecuador, the Philippines, Bangladesh, Mexico and Brazil. Professor Ivan Valiela and colleagues at the Boston University Marine Program reported (2001) that conversion to shrimp aquaculture is responsible for 38% of total mangrove destruction, and that 'shrimp culture is, by a considerable margin, the greatest cause of mangrove loss. In at least 12 countries, wetland sites listed as having international importance under the Ramsar Convention have been damaged or destroyed (04Q1).
Restoring mangroves cost US$10,000 to $100,000/ km2. Yet loggers and shrimp aquaculture prospectors can lease mangrove forests for a few hundred $/ km2 (00M1). The total ecological value of mangroves in terms of food production, storm protection and waste treatment has been estimated at about US$1,000,000/ km2/ year (00M1). This is the cost of providing the same services by other means.
Mangrove forest loss in selected countries since pre-agricultural times (93W3) (All losses and inventories are in km2) Source: WRI, UNEP 1990, Australian Institute of Marine Science (1992).
|
Indonesia |
21220 |
(45% of 47,116) |
|
Nigeria |
12320 |
(50% of 24,640) |
|
Malaysia |
7384 |
(32% of 23,075) |
|
Cameroon |
4908 |
(40% of 12,270) |
|
Sierra Leone |
3434 |
(50% of ~6,868) |
|
Guinea-Bissau |
3183 |
(70% of ~4,547) |
|
Bangladesh |
2940 |
(73% of ~4,027) |
|
Mozambique |
2787 |
(60% of ~4,645) |
|
Tanzania |
2142 |
(60% of ~3,570) |
|
Philippines |
785 |
(80% of ~ ~981) |
|
Total |
61103 |
(46% of*131,739) |
* (of countries on list)
Mangrove Areas in Selected Countries ((00W3), p. 74) Data of Burke et al [PAGE] 2000, (Areas are in km2 ) (Extent is current.)
|
Country |
Extent |
Loss |
Period |
|
Angola |
1100 |
50% |
Original-1980s |
|
Coted'Ivoire |
640 |
60 |
Original-1980s |
|
Gabon |
1150 |
50 |
Original-1980s |
|
Guinea-Bissau |
3150 |
70 |
Original-1980s |
|
Kenya |
610 |
4 |
1971-88 |
|
Tanzania |
2120 |
60 |
Original-1980s |
|
Costa Rica |
413 |
-6 |
1983-90 |
|
El Salvador |
415 |
8 |
1983-90 |
|
Guatemala |
161 |
31 |
1960s-90s |
|
Jamaica |
106 |
30 |
Original-1990s |
|
Mexico |
5315 |
65 |
1970s-90s |
|
Panama |
1581 |
67 |
1983-90 |
|
Peru |
51 |
25 |
1982-92 |
|
Brunei |
200 |
20 |
Original-1986 |
|
Indonesia |
24237 |
55 |
Original-1980s |
|
Malaysia |
2327 |
74 |
Original-1992-93 |
|
Myanmar |
4219 |
75 |
Original-1992-93 |
|
Pakistan |
1540 |
78 |
Original-1980s |
|
Philippines |
1490 |
67 |
1918-80s |
|
Thailand |
1946 |
84 |
Original-1993 |
|
Vietnam |
2625 |
37 |
Original-1993 |
|
Papua New Guinea |
4627 |
8 |
Original-1992-93 |
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 Ref. (99M1)). 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.
Loss of mangrove forest results in increased sediment transport onto downstream coral reefs (Ref. 37 of Ref. (00N1)). (Coral reefs depend on sunlight for their existence.)
Shrimp are often produced by clearing coastal mangrove forests that protect coastlines and serve as nurseries for local fish. Mangrove destruction can cause a decline of local fisheries that will actually exceed the gains from shrimp production, leading to a net protein loss (00W2).
Part [H3] ~ Reefs ~
Up to 70% of the world's shallow reefs could be gone in the next few decades (01R2).
25% of the world's original reefs have been lost (01R2). Those remaining are under stress from pollution, sedimentation, destructive fishing practices and global climate change (mainly ocean warming) (01R2).
About 30% of the world's coral reefs are healthy (~2004), down from 41% in 2002, according to a study released 12/6/04 by 240 scientists in 96 countries (04H1). (The study's lead author, Clive Wilkinson, is coordinator of the Global Reef Monitoring Network.)
Between 1992 and 2000, the share of severely damaged reefs. worldwide, expanded from 10 to 27% (00W5).
27% of the world's original coral reefs have been lost, 14% of the remaining reefs are expected to be destroyed in the next 10-20 years. In 2002, more than 400 of the world's reefs suffered bleaching. Reefs in eastern Africa and the Indian Ocean continue to degrade because of sediment and nutrient runoff and over-exploitation of reef resources. 60% of the Great Barrier Reef (Australia) was bleached in 2002. Some inshore reefs suffer up to 90% coral death ("Coral Reefs Start Slow Recovery", BBC News (12/2002)).
Trawling has been around 100 years, since the advent of powerboats. However, corals at least 800 years old are being destroyed as 14.8 million km2/ year are trawled worldwide (00L1). This is a significant portion of the world oceans' area of continental shelves.
58% of the world's coral reefs are imperiled by humans. (UN report on global ecosystems (9/2000).) The $4 million study is the outcome of a program called Pilot Analys