420 likes | 529 Views
Over Fishing the Oceans. WHAT IS THE PROBLEM?. Fishery = industry of catching, processing or selling a fish, shellfish, or other aquatic organisms Worldwide 40% to 50% of commercial fisheries are fully exploited (fished at their maximum biological productivity)
E N D
WHAT IS THE PROBLEM? Fishery = industry of catching, processing or selling a fish, shellfish, or other aquatic organisms Worldwide 40% to 50% of commercial fisheries are fully exploited (fished at their maximum biological productivity) with an additional 24% either over-exploited or depleted (fished to the point that reproduction is reduced)
Up to 90% decrease since WW II in large ocean fish, including bottom-dwelling groundfish like cod, and swimmers like tuna, swordfish, marlin, and sharks
As a result of intense, unrestricted fishing many shark species populations have decreased by more than 95%, and 42% of species are threatened with extinction.
Pacific cod & halibut fisheries have been closed all along the West Coast since September 2002 to save rockfish, which are down to 4% of former numbers in many areas
As fish stock decrease smaller fish are being captured, many before they mature (become able to reproduce), i.e. swordfish
In Alaska spawning pink salmon average size has decreased by 35% over two decades, because only those small enough to fit through the mesh of a gill net survive to reproduce (these are genetic changes, are they permanent?)
Orange Roughy, that live 150 years and take decades to mature, have gone from abundant to scarce in a few years. Now, newly “discovered” species are following the same pattern.
The North Pacific crab industry has collapsed, and an 80% catch reduction has been imposed. The fishery is looking for $100 million in federal assistance.
Shrimp stocks in the Gulf of Mexico have dwindled to 30% of their historic levels and may soon reach a point where reproduction will not be able to replenish stocks.
The northwest Atlantic cod has been regarded as heavily overfished throughout its range, resulting in a crash in the fishery in the U. S. and Canada during the early 1990s. Newfoundland's northern cod fishery can be traced back to the 16th century. On average, about 300,000 tonnes of cod were landed annually until the 1960s, when advances in technology enabled factory trawlers to take larger catches. By 1968, landings for the fish peaked at 800,000 tonnes before a gradual decline set in. With the reopening of the limited cod fisheries in 2006, nearly 2,700 tonnes of cod were hauled in. In 2007, cod stocks were estimated at one per cent of what they were in 1977.
The Visayan Sea MarineTriangle is considered to be the most biologically diverse marine area in the world. Elpido de la Victoria, a leader in a campaign to persuade the Philippine government to close the Visayan Sea Marine Triangle to commercial and destructive forms of fishing, was shot in the back and killed on April 13, 2006. Commercial fishing interests collected $20,000 for a bounty to have him killed.
Why is there still so much fish available at the market? There is no need to worry about endangered Chinook salmon because you can “buy a can of salmon off the shelf” at the grocery store. Helen Chenoweth, R, Idaho
Most salmon, shrimp, & shellfish come from fish farms or aquaculture, not wild sources. Over 80% of the seafood Americans eat is imported. Historical shrimp aquaculture
1998 U.S. Aquaculture ProductionValue of Prominent Farmed Marine Animal by Key-Producing States The major marine animals farmed in the United States are salmon, clams, oysters, and shrimp. The 1998 production of these organisms is recorded here as the value of the farmed product in millions of dollars.
Increased Harvest Previously fishing was a matter of wresting sustenance from a hostile sea using tiny boats and simple gear, but modern “Industrialized Fishing” uses new equipment & technology with international fleets that fish year-round
Amount of fish caught has increased by over 5 times in 50 years
Food webs contain fewer trophic levels when overfishing occurs, which disrupts ecosystems
Improved technology to find fish • Fishfinders (sonar) • Satellites • Aircraft With today’s improved technology a recreational fishfinder’s motto has become the truth “The Fish Have Nowhere to Hide”
Improved methods for capturing fish Drift nets
Drift nets are up to 150 miles long and catch many species indiscriminately, often becoming lost and continuing to “fish” for years.
Improved methods for capturing fish Long-lines with baited hooks Longlines can be many miles long and carry thousands of hooks. Longlines are not anchored and are set to drift near the surface of the ocean with a radio beacon attached so that the vessel can track them to haul in the catch.
A single boat can set 60 miles of line baited with 10,000 hooks. Longlines are the most widely used fishing gear on Earth. They catch many unintended species, including 40,000 sea turtles, 300,000 sea birds and millions of sharks per year. Thrown dead or dying back into the ocean, these unwanted species make up at least 25% of the global catch each year.
Improved methods for capturing fish Bottom trawlers
Imagine burning down a forest to flush a few quail. By razing seafloor ecosystems, trawlers – the brutal equivalent of fishing the seafloor with bulldozers – level an area 150 times larger than the total area of forests clearcut on land each year.
Atlantic Cod Fishery as an example of the problem Technologies that contributed to the collapse of Atlantic cod include engine-powered vessels and frozen food compartments aboard ships. Engine-powered vessels had larger nets, larger engines, and better navigation. The capacity to catch fish became limitless. In addition, sonar technology gave an edge to catching and detecting fish. Sonar was originally developed during WWII to locate enemy submarines, but was later applied to locating schools of fish. These new technologies, as well as bottom trawlers that destroyed entire ecosystems, contributed to the collapse of Atlantic cod. They were vastly different from old techniques used, such as hand lines and long lines. The fishery has yet to recover, and may not recover at all because of a possibly stable change in the food chain. Atlantic cod was one of the top-tier predators, feeding upon smaller prey, such as herring, capelin, shrimp and snow crab. With the large predatory fish removed, their prey have had population explosions and have become the top predators, affecting the survival rates of cod eggs and fry.
Bycatch is the nontarget fishesand other marine life that are caught Bottom trawling, is responsible for 80% of all bycatch incurred globally.
Other Contributors to the Overfishing Problem • Government subsidies of unprofitable fisheries • 1982 U.N. Convention on the Law of the Sea which allowed countries bordering the ocean to claim exclusive economic zones reaching 200 nautical miles from shore • Aquaculture, or fish farming, requires three pounds of wild fish to produce every pound of salmon that goes to market – which depletes additional fisheries that had been spared intense fishing pressure. • Aquaculture also creates considerable pollution and infects wild populations with disease. • Increasing demand for seafood.
WHAT ARE SOME SOLUTIONS? “The task at hand is to manage the fisheries with a view to ensuring sustainable utilization of the food available in the oceans for the benefit of present and future generations without harming the ecosystems capacity to support human life” Dr. Jacques Diouf, at an international conference on responsible fisheries
Ecosystem-based management including marine reserves or “no-take zones”
Greenpeace’s Carting Away the Oceans (CATO) project tracks and reports on progress being made in the seafood sector. Public support for conservation measures has pushed groceries of all sizes to offer sustainable seafood and eliminate the “unsustainable” alternatives. Unfortunately, there are still numerous seafood retailers that have yet to take any responsibility for the seafood they sell, or for the damage they are doing to our oceans.
Dramatically reduce global fleet capacity Enforce restrictions on gear that harms habitats or that capture “bycatch” species that will be thrown away.
Abolish government subsidies that keep unprofitable fishing fleets afloat “The fish harvesting industry in the U.S. isn’t run like a business, and you can’t prove the U.S. fish harvesting industry is financially solvent” Zeke Grader Jr. executive director of the largest active trade association of commercial fisherman on the U.S. west coast U.S. taxpayers paid more than $6.4 billion in subsidies to the commercial fishing industry between 1996 and 2004, possibly accelerating the ongoing collapse of fish stocks worldwide and adding to the devastation of large ocean fish species.
According to new report in Conservation Biology if global fisheries are to be made sustainable the amount of subsidies large-scale industrial fishing receivesmust be reduced • For this study, small-scale refers to operations which use; • boats 15 meters or shorter • less energy-intensive fishing gear (in general) • operate close to shore • The report says; • Large-Scale or Industrial Fisheries • generally use destructive fishing techniques (e.g. bottom trawling) • discard 8-20 million tonnes of unwanted fish annually • mostly target fish not intended for human consumption but instead for processing into fishmeal used as livestock feed • Small-Scale Fisheries • generally use more benign fishing methods • can target different fish species based on local availability. • create more jobs, employing 25 times the number of people as large-scale industrial fishing • use 75% less fuel to catch the same amount of edible fish as industrial fishing
Fuel Subsidies Make Industrial Fishing Viable • The prime reason that industrial fishing is viable, according to this report, is that government subsidies--in particular fuel subsidies totaling globally some $6.3 billion annually--tilt the playing field in favor of large-scale fishing. • Given that small-scale fisheries catch four times as many fish per liter of fuel consumed as do large-scale fisheries, if these fuel subsidies were removed it "would render the 200-strong fleet of high-seas bottom trawlers unprofitable." • Additional annual subsidies detailed in the report, which favor large-scale fisheries more than small-scale, are; • $8 billion in fishing port construction and renovation • $5.8 million in fisheries management programs and services • $1.9 million in boat construction and renovation • $1 million in fishing access agreements • $0.7 million in tax exemptions.