• Overfishing

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    The Global Impact

    Overfishing of sharks only for their fins

    Overfishing of sharks only for their fins

    Marine and freshwater resources are being exploited. Worldwide, 1,414 species of fish—5 percent of the world’s known species—are on the IUCN red list, at risk for extinction.[49. Animal Planet. Discovery. “10 Most Endangered Fish Species.” animal.discovery.com]

    Ten years ago, we reached the maximum levels of catch that populations of bottom fish and small pelagic fish could sustainably handle.[50. FAO. “State of the World’s Fisheries 2012.”] Now, fisheries are catching fish from populations that are already depleted! This lack of long-term thinking could sink the entire fish industry. The conservation of fish populations should be a central focus of fisheries –if the fish don’t exist then what are they fishing for.

    Because of the multitude of issues with wild-caught fish populations, there is an increase in aquaculture, or fish farms. It’s expected that from now on half of the fish consumed in the world will come from aquaculture. More than 50 million tonnes of fish and seafood are already bred in freshwater and ocean hatcheries.[51. Retail Forum for Sustainability. European Union. “Sustainable Seafood.” Issue Paper No. 9, June 2012.]

    Loss of Food Source

    Fish market

    Fish market

    Fish provides more than 7 billion people with almost 15 percent or more of their dietary animal protein.[52. FAO. “State of the World’s Fisheries 2012.”] In developing countries, fish are an affordable food and may be part of their local cuisine.[53. FAO. “State of the World’s Fisheries 2012.”] Losses of fish stocks will impact the price of fish – which are already rising in response to demand and increasing costs of fishing.

    Rising prices for seafood makes global trade attractive for all countries. In 2010, developing countries exports made up 50 percent of the value of global fish trade.[54. FAO. “State of the World’s Fisheries 2012.”] Increasing demand for fish has countries exporting more of their catch for international trade – which is limiting locally caught fish available to local markets.[55. Fisheries and Oceans Canada, “Overfishing and Food Security.”]

    In Africa, Asia, Latin America and islands in the Pacific and Indian Oceans, artisanal fishers provide the bulk of fish for poor communities.[56. Fisheries and Oceans Canada, “Overfishing and Food Security.”] The cost of keeping up to commercial fleets—competing for space, resources and markets—may be the end of many small-scale fisheries. Already in South and Southeast Asia, small fish operations are being taken over by large companies. In rural areas of developing countries, where significantly more people rely on fishing and there are fewer alternative livelihoods – the depletion of our fish life will be especially felt.[57. FAO. “Ethical Issues in Fisheries. Main ethical issues in fisheries.”]

    Loss of Livelihood

    Fishing for people across the globe is not just for recreation or as a source of food, it is their way of life and how they support themselves and their family. In the Senegalese fisheries sector overfishing has already led to 80 percent unemployment.

    820 million people worldwide are employed by fishing industry

    820 million people worldwide are employed by fishing industry

    All the economic impacts of fishing add up to $240 billion (US) annually, of which revenue from marine ?sheries comes in around $85 billion.[58. PEW Environment Group. “Marine Fisheries and the World Economy.” 2010.] In 2010, there were 54.8 million fishers and fish farmers, however, 60 to 820 million people are estimated to be employed by the numerous fishing-related jobs in fish processing, packaging, marketing and distribution; equipment and gear manufacturing; ice production; administration; and research.[59. FAO. “State of the World’s Fisheries 2012.”]

    The World Bank and the United Nations’ Food and Agriculture Organization estimated that overfishing might cost the world roughly $50 billion (US) a year in net economic losses.[60. FAO. “State of the World’s Fisheries and Aquaculture. 2012.”]

    In the last decade, in the North Atlantic region, commercial fish populations of cod, hake, haddock and flounder have fallen by as much as 95 percent. Experts recommend fishing be stopped to allow populations to recover. In 1992 the collapse of the cod fishery – off Canada’s east coast—lead to the loss of 40,000 jobs.

    If one species declines, fisheries expand their fishing areas and efforts or simply target another species. Global fishing needs to be reduced by about 50 percent to make fisheries more economical and allow fish populations to be sustainable.

    Harder to Catch

    It’s taking more effort—labour and better-equipped fleets—to catch enough fish now, to meet consumers’ growing demand for seafood.

    Increasing effort may make some fisheries too expensive to operate. Government subsidies allow fisheries to continue even when the costs of the fleet exceed the value of the catch –more than $10 billion (US) in subsidies is paid out per year.[61. World Ocean Review. “The causes of overfishing.”]

    The swordfish caught off the North American coast in the 1860s weighted 270 kilograms compared to 100 kilograms today.[62 coml.org] The decreasing in fish size is also decreasing the value of the catch. As it becomes harder to catch large, valuable fish, fishers switch their focus and gear to take smaller and often less valuable species.[63. World Bank. “State of the World’s Fish Stocks.” September 2006.]

    Lost Species

    90 percent of all large predatory fish – including tuna, sharks, swordfish, grouper (above), cod and halibut – are gone.

    90 percent of all large predatory fish – including tuna, sharks, swordfish, grouper (above), cod and halibut – are gone.

    If overfishing continues, more species will be driven to extinction and aquatic ecosystems will collapse. Fisheries should behave responsibly because they are major forces of ecological and evolutionary change.[64. Trends in Ecology and Evolution. “The Future of Fish.” Boris Worm. August 2012.]

    90 percent of all large predatory fish – including tuna, sharks, swordfish, cod and halibut – are gone.[65. Save our Seas. & Greenpeace International]

    Over the past 100 years we’ve managed to outfish and mismanage many marine species. Some commercially important species common before the 1950s such as Chinese bahaba, Hong Kong grouper, Knobsnout parrotfish, and Blackspot tuskfish are now commercially extinct.[66. World Wildlife Fund Hong Kong. www.wwwf.org.hk]

    The 1990s saw the collapse of several major Atlantic cod fisheries, including Canada’s cod fishery off Newfoundland in 1992, which has still not recovered.[67. Save our Seas.] The cod stocks in the North Sea and Baltic Sea are now close to collapse. Argentinian hake stocks collapsed in 1997 after years of overfishing, and caused massive unemployment.[68. “Overfishing and other threats to aquatic living resources.” marinebio.org]

    The giant clam is one of only a few invertebrates on the IUCN Endangered Species List[69. “Marine protected areas for sustainable fisheries: Layang Layang reef as a source of larvae in the South China Sea.” Steve Oakley and Nicolas Pilcher] thanks to overfishing. Giant clams have been overfished for meat and shells and are now locally extinct throughout tropical Indo-Pacific waters.[70. “Marine protected areas for sustainable fisheries: Layang Layang reef as a source of larvae in the South China Sea.” Steve Oakley and Nicolas Pilcher]

    The live fish trade has overfished most reefs in the South China Sea to satisfy demand for large rare fish like the Napoleon wrasse (endangered).[71. “Marine protected areas for sustainable fisheries: Layang Layang reef as a source of larvae in the South China Sea.” Steve Oakley and Nicolas Pilcher] Large fishes that live on coral reefs such as groupers, snappers, emperors and wrasses – from the South China Sea and the Caribbean – have either disappeared or become very rare due to overfishing.[72. FAO. Assessment.]

    Examples of species caught for food that is in danger from overfishing:

    1. Sharks
    2. Groupers
    3. Tuna
    4. Salmon
    5. Marlin
    6. Halibut
    7. Cod
    8. Monkfish
    9. Snapper
    10. Sturgeon
    11. Skate
    12. Orange Roughly
    13. Rockfish
    14. Whitefish
    15. Swordfish
    16. Flounder

    Wildlife discarded

    Shark on Longline

    Shark on Longline

    Bycatch from longlining, bottom trawling and other fishing techniques is killing an overwhelming numbers of non-targeted fish. Sea turtles, seabirds and marine mammals such as dolphins, seals, manatees and sea lions are all being caught unintentionally and often are discarded.[73. FAO. Assessment.] Experts calculate global bycatch to be 27 million tonnes for a 77-million-tonne catch![74. Endangerd Species Research. “Global seabird bycatch in Longline fisheries. Anderson, O. et al. June 8, 2011.]

    Studies estimate that each year longlining kills at least 160,000 to 320,000 seabirds—albatrosses, petrels and shearwaters.[75. Sea Shepherd Conservation Society. “Longlining.”] Longlines are now the most serious threat to albatross, with 12 of the 14 species suffering significant population losses from longlines.[76. Bycatch: The Effects of Pelagic Longlining on Pacific Sea Turtle Populations. Frances Kinslow.] Longlines are also one of the biggest causes of sea turtle deaths. In 2000, roughly 200,000 loggerhead turtles were killed as bycatch on longlines as well as 50,000 critically endangered leatherbacks.[77. The PEW Charitable Trusts. “Campaign to End Overfishing in the Southeast.” 2012.]

    Losing Top Predators

    In the long-term, overfishing can have a devastating impact on ocean communities: it removes key players from food webs, destroys the natural habitats of many aquatic species and initiates a cascade of effects.

    Ocean Ecosystem

    Ocean Ecosystem

    Some of the most popular species in our diets are top predators in the ocean food chain – such as tuna and groupers. Apex predators tend to be larger, longer-lived and late to mature, making them more vulnerable than other species to overfishing. Removing a top predator leads to an overabundance of their smaller prey, like sardines and anchovies, this causes changes throughout the ecosystem as each species adjusts and impacts each other. It can also take time to build up fish populations when they have been overfished. In the Gulf of Mexico the red snapper have been overfished for nearly 20 years – and could take 30 years or more to recover.[78. Census of Marine Life. “Effects of Shark Decline.” 2009. www.coml.org]

    Fisheries will “fish down the food chain” and switch to other lesser-valued species according to what consumers will accept. For instance, the orange roughy is a smaller such species and was renamed (from slimehead) to make it more consumer appealing – now orange roughy is in trouble of being depleted.

    The Disappearance of Sharks

    100 million sharks are killed each year for shark fins, not accounting for other deaths, which could be two to three times higher.

    Shark finning

    Shark finning

    For decades fisheries along the United States’ Atlantic Coast ate away at species of larger-sized sharks, such as the scalloped hammerhead, for shark meat and shark fins. Each year, thousands of sharks were also caught as bycatch by other fisheries with swordfish and tuna. As apex predators, these sharks were at the top of the food web in their habitats; 11 shark species fed on rays, skates and smaller sharks thereby controlling their populations.[79. Census of Marine Life. “Effects of Shark Decline.” 2009. www.coml.org]

    More than 30 years of overfishing impacted all 11 shark species – and impacted the ecosystems they are part of.[80. Live Science. “International Shark Trade to be Regulated.” Megan Gannon, March 11, 2013. www.livescience.com] Now more than 95 percent of the scalloped hammerhead, tiger, bull, dusky and smooth hammerhead sharks in the northwest Atlantic are gone.

    As the sharks disappeared, their prey grew in number. Populations of 12 species of skates, rays and smaller sharks that had been controlled by predation from sharks, increased. Numbers of cownose rays exploded and cleaned out bay scallops –causing the North Carolina bay scallop fishery to shut down in 2004. An apex predator, like the shark, keeps their ecosystems in balance. Sustainable fisheries need to maintain top-level predators to keep their fisheries alive, as well as oceans.

    Cownose ray populations grew after their predators decreased, causing a ripple effect on the scallop industry.

    Cownose ray populations grew after their predators decreased, causing a ripple effect on the scallop industry.

    Shark protection got a boost in March 2013 when seven species of shark got voted in for international protection. The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) will control the international trade of five species of sharks that are threatened by overfishing — Oceanic whitetip sharks, porbeagle sharks, scalloped hammerheads, great hammerheads and smooth hammerheads. Only two other shark species (basking and great white) have the same CITES protection.[81. PEW Charitable Trust. “Global Tuna Conservation.” Jan. 2013.]

    Destroying Coral Reefs

    Coral reefs are the second most productive ecosystems in the world behind rainforests – but overfishing destroys that biodiversity. Coral and fish live an intertwined life: corals provide habitat and food, while fish graze the algae that corals compete with for space.

    Coral reef

    Coral reef

    When overfishing robs reefing of fish, algae takes over, smothering coral and replacing it with a new ecosystem severely lacking in biodiversity.

    No More Tuna

    Millions of people rely on tuna for protein and as apex predators they play a crucial role in balancing marine ecosystems.[82. Time. Science & Space. “The Pacific Bluefin Tuna is Going, Going..” Bryan Walsh. Jan. 11, 2013.] Bluefin tuna are the largest tuna – and Japan consumes 80 percent of the bluefin tuna caught worldwide. As one of the largest and fastest fish at 70 kilometres an hour, they are swimming powerhouses with torpedo-shaped, streamlined, high-powered bodies that have evolved for high endurance on long-distance migrations.

    Coveted for sushi, overfishing of bluefin tuna has brought its populations in the Atlantic and Pacific oceans close to collapse. An assessment released in January 2013, estimates that Pacific bluefin tuna has declined by 96 percent.[83. Time. Science & Space. “The Pacific Bluefin Tuna is Going, Going..” Bryan Walsh. Jan. 11, 2013.] Ninety percent of Pacific bluefins are caught young before they can reproduce in their Mediterranean breeding grounds.[84. FAO. World…Fisheries…]

    Industry has begun fattening up young fish captured from the wild in ocean cages to increase their size for market. One bluefin tuna can weigh in at 600 kilograms and more than three metres in length. Loved for its high-end meat, bluefin tuna pitch a high price tag and support a $7.2 billion (US) industry.

    1. Species is IUCN Listed
    2. Southern Bluefin Tuna is Critically Endangered
    3. Pacific Bluefin Tuna is Least Concern
    4. Atlantic Bluefin Tuna is Endangered

    Significant demand for tuna and overfishing have led to a global decline in all tuna populations including the skipjack and the yellowfin – yet the fishing continues. Of the seven fished tuna species (there are 23 species overall), more than 70 percent of their populations are fully exploited or worse.[85. SciDev.net. “Pacific fisheries meet fails to end tuna overfishing.” Prime Sarmiento. Dec. 11, 2012] Despite these shocking statistics, tuna catches remained stable – in 2010, 6.6 million tonnes of tuna and tuna-like species were caught.

    Yellowfin tuna is the on the brink of being overfished, like other tuna species

    Yellowfin tuna is the on the brink of being overfished, like other tuna species

    A meeting of the Western and Central Pacific Fisheries Commission (WCPFC) in December 2012 failed to address how to stop overfishing of bigeye tuna as demanded by a group representing eight nations of Oceania.[86. SciDev.net. “Pacific fisheries meet fails to end tuna overfishing.” Prime Sarmiento. Dec. 11, 2012]

    In fact, discussions covered how much overfishing to allow. The bigeye tuna is fished 40 percent above its sustainable level. The WCPFC is the governing body for an international fisheries agreement for the conservation and sustainable use of highly migratory fish. Because tuna are migratory, countries must manage and preserve tuna fisheries together.

    Globally we must put a stop to overfishing: for the sake of our ecosystems, planet and for all the humans that depend on fish as a source of food and work.

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