Overfishing aff inherency
Trawling and long line fishing
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- Bottom Trawling devastates marine ecosystems and endangers the species there
- Long line fishing threatens many species
- Long line fishing will cause sea turtles to go extinct
- Long line fishing is responsible for the huge population declines of sharks and other large predatory fish species
- Sea birds, especially albatross, are being killed off by longline fishing
- Catch shares solve for detrimental long line fishing
- Individual quotas stop long line fishing practices
- Individual quotas will deal with long line fishing and trawling
Trawling and long line fishingGeneral--Hurts SpeciesTrawling causes reduction in fish population faster than other fishing practicesHiddink et. al 11 “Could our fisheries be more productive? Indirect negative effects of bottom trawl fisheries on Fish Condition” Journal of Applied Ecology, Jan G. Hiddink*, Andrew F. Johnson, Rachel Kingham and Hilmar Hinz 2011, 48, 1441–1449 accessed 6/30/14 via Wiley Online Library Our results provide partial support for the hypothesis that bottom trawling negatively affects the fitness of benthivorous fish by reducing the availability of food. The condition of benthivorous plaice was negatively related to trawling frequency, and this could be explained by a reduction in the production of infauna. Density-dependent effects such as competition could not have played a role in generating this relationship as plaice had the worst condition at the stations where they were least abundant and therefore where competition for food resources was expected to be the lowest. The hypothesized positive effect of low trawling frequencies (<2 year)1 on the abundance of the food for plaice or the condition of plaice (Hiddink, Rijnsdorp & Piet 2008) could not be detected in this study because only one of the stations covered this range of trawling intensities. This hypothesis therefore remains untested. The condition of benthivorous dab however was not related to trawling frequency or infaunal production and does therefore not support our hypotheses. The relationship between trawling and condition for the piscivorous whiting provides a ‘control treatment’ that takes account of any other effects bottom trawling may have on fish condition that are not related to food availability. As hypothesized, no effect of bottomtrawling on the condition of whiting was detected. The lack of an effect of trawling on dab may be explained by its diet composition, as dab has a highly opportunistic feeding strategy making it more adaptable to habitat and ecosystem change compared with other species (Hinz, Kro¨ ncke & Ehrich 2005). Dab might be able to feed and maintain its condition regardless of changes in benthic community structure, while more selective benthic feeders such as plaice might not be able to compensate for the loss of particular prey types. In addition, dab is known to scavenge more extensively than plaice and whiting on dead and dying invertebrates in trawled areas (Groenewold & Fonds 2000). This means that the food availability for dab is likely to be less strongly affected by bottom trawls than for plaice. Bottom trawling reduced the abundance of the fish at the same time as reducing food production. The ramifications for the fish depend on the relationship between the amount of prey available and the demand on the reduced food supply by the remaining fish. Energetically, it is likely to be more costly to forage in low-production compared with high-production patches. In areas of low benthos, fish will have to spend more time searching for prey (e.g. Charnov 1976), and therefore, lowering their intake rates while increasing energy expenditure. This means that if bottom trawling leads to a decrease in the carrying capacity for benthos of the ecosystem, fish production is likely to drop, even if the amount of food per fish stays equal. Furthermore, fish numbers decrease linearly with fishing effort, but benthic invertebrate production has been shown in previous studies to drop very sharply even at low levels of bottom trawling (Hiddink et al. 2006). Fish numbers may not always decrease linearly with fishing effort because catchability can depend on fish density, but this effect tends to lead to a faster depletion of prey than of the fish. This means that both the amount of food production per fish and the food intake per fish is likely to decrease as a result of bottom trawling. Bottom Trawling devastates marine ecosystems and endangers the species thereLighthouse Foundation ‘07 ("Destructive Fishing Practices and Bycatch." - Ocean Threats. Lighthouse Foundation, n.d. Web. 13 Jun. 2007. http://www.slowfood.com/slowfish/pagine/eng/pagina.lasso?-id_pg=43) Destructive Fishing Practices and Bycatch¶ ¶ As fish stocks decrease, fishing methods become increasingly extreme.¶ ¶ Destructive fishing practices devastate the marine environment and include bottom trawling, bycatch, the use of poison and explosives and ghost fishing.¶ ¶ When fishing techniques have been universally recognized as destructive, the only solution is to ban them. Anyone continuing to use these techniques must be severely punished. National legislations have identified and banned many of these practices. However, the temptation to break the law is very high both for factory ships on the hunt for huge profits and small-scale fishermen facing reduced fish stocks.¶ ¶ Clearly, the larger and better-equipped the boats, the more devastating the impact of illegal fishing techniques. ¶ ¶ One of the most harmful techniques is bottom trawling, an industrial method which uses enormous nets weighed down with heavy ballast which are dragged along the sea floor, raking up or crushing everything in their way, from fish to ancient coral. ¶ ¶ Many species, including those at risk of extinction, are accidentally caught and then thrown back into the sea, often already dead. These collateral losses, known as discards, can reach up to 80% or even 90% of the total catch.¶ ¶ Large areas of the seabed, the habitat where fish find food and shelter, are crushed and flattened. The biggest nets used for bottom trawling have a mouth the size of a rugby pitch and leave scars on the seabed more than 4 kilometers long. The damage caused to the ecosystem can be permanent. Bottom trawling also churns up sediment (sometimes toxic), creating turbid water inhospitable to life. This type of fishing obliterates the natural environmental features where marine animals would normally live, rest and hide.¶ ¶ Often used by industrial boats in the high seas, sometimes regulated in territorial waters, this practice, accused of having contributed heavily to overfishing, is a striking illustration of the lack of global fisheries management.¶ ¶ Seabed ecosystems are characterized by exceptional biodiversity. Over the last 25 years, scientific studies have identified very rich marine environments at depths greater than 400 meters, down to 2,000 meters and more. Despite almost complete darkness, strong pressure and very weak currents, a huge number of species can be found in these deep waters.¶ ¶ Living in extreme conditions, deep-water fish grow very slowly and have a long life expectancy and a late reproductive age. As a result, they are particularly vulnerable to disturbances in their environment. At-risk marine ecosystems are not only in the high seas; bottom trawling on underwater mountains and the steep continental slopes on the edge of the shelf can also cause serious damage.¶ ¶ The scientific community and many NGOs are calling for an international moratorium to protect the seabed from bottom trawling, but government efforts to support this have so far been minimal. ¶ ¶ By catch¶ ¶ One of the most shocking aspects of ocean pillaging.¶ ¶ Bycatch refers to all the forms of marine life caught unintentionally while catching other fish. Bycatch can include the wrong size of the target species, other species that are not eaten or for which there is no market and banned or endangered species such as certain birds, turtles and marine mammals. Some fish are discarded because the fishing boat is not licensed to bring them to land, because there is no space on the boat or because the captain has decided not to catch that species. The great proportion of bycatch, millions of tons each year, is thrown back into the sea dead or wounded. ¶ ¶ A recent WWF report estimates that by catch represents 40% of global marine catches, and that in many cases the fish discarded are juveniles. It is easy to grasp what dramatic consequences such devastation has on the ability of a species to reproduce and regenerate stocks.¶ ¶ Beyond the pressure on marine species, bycatch represents amonstrous waste of food, for both humans and marine predators.¶ ¶ Experts emphasize that while industrial fishing boats throw millions of tons of undesired fish back in the sea each year, artisanal fishing discards are very small.¶ ¶ Poison and Explosives¶ ¶ The use of poison to kill or stun fish is very common, in both fresh and salt water, including coastal lagoons and coral reefs. Cyanide fishing, for example, is used on the now-devastated reefs of the Philippines – where an estimated 65 tons of cyanide are poured into the sea each year – and those in eastern Indonesia and other western Pacific countries.¶ ¶ In many places the use of poison to catch fish is a traditional technique, but negative effects have multiplied since plant-based substances were replaced by chemical poisons. These kill all the organisms in the ecosystem, including the corals forming the reef. ¶ ¶ The use of explosives for blast fishing has also been around for centuries and is on the increase. Explosions can produce very large craters, devastating between 10 and 20 square meters of the sea floor. They kill not only the target fish, but all the other surrounding fauna and flora. In coral reefs, reconstruction of the damaged habitats can take decades.¶ ¶ Explosives are easily and cheaply purchased and often come from the mining or building industries. In many regions, explosives are extracted from old munitions from past wars or current conflicts. Elsewhere, fishermen buy them through the illegal arms trade.¶ ¶ Ghost Fishing¶ ¶ Ghost fishing is the result of nets and other fishing materials that are accidentally or intentionally abandoned in the sea. These nets continue to senselessly trap fish and shellfish and even large marine mammals, which die of exhaustion or suffocation after struggling to get to the surface to breathe. The problem of abandoned or lost equipment has been amplified by increased fishing activity and the introduction of nets and line made from long-lasting synthetic material. ¶ Long line fishing threatens many speciesOvetz 2006 (Robert, Professor Robert Ovetz from College of Marin: Kentfield Kentfield, CA. and Sea Turtle Restoration Project, “The bottom line: An investigation of the economic, cultural and social costs of industrial longline fishing in the Pacific and the benefits of sustainable use marine protected areas”, Marine Policy Volume 30, Issue 6, November 2006, Pages 809–820, EBSCO) Pelagic longline fishing in the Pacific is a highly unselective fishing technique that uses monofilament lines at the shallow surface of the high seas stretching as much as 60 US miles with as many as thousands of baited hooks. These large vessels originate from a number of countries including the US, Japan, Taiwan, Spain and other Asian and Latin American countries and primarily export their catch to the US, Japan and the European Union. Targeting highly migratory predatory fish species including tuna and swordfish, industrial longlines also catch or kill as many as 4.4 million sea turtles, billfish, sharks, marine mammals and seabirds [2] and [3].2 Sea turtles I/LLong line fishing will cause sea turtles to go extinctOvetz 2006 (Robert, Professor Robert Ovetz from College of Marin: Kentfield Kentfield, CA. and Sea Turtle Restoration Project, “The bottom line: An investigation of the economic, cultural and social costs of industrial longline fishing in the Pacific and the benefits of sustainable use marine protected areas”, Marine Policy Volume 30, Issue 6, November 2006, Pages 809–820, EBSCO) Most threatened by industrial longline fishing are leatherback sea turtles which migrate thousands of miles across the Pacific to lay their eggs, feed and reproduce. According to recent scientific reports, the number of nesting female Pacific leatherback sea turtles has declined by 95% since 1980 and is expected to go extinct within the next 5–30 years unless efforts are taken to reverse their decline [4], [5] and [6]. One of the largest threats to their survival is pelagic industrial longline fishing. Leatherback sea turtles get hooked on longlines and often drown before the line is reeled and the sea turtle can be released. Sharks I/LLong line fishing is responsible for the huge population declines of sharks and other large predatory fish speciesOvetz 2006 (Robert, Professor Robert Ovetz from College of Marin: Kentfield Kentfield, CA. and Sea Turtle Restoration Project, “The bottom line: An investigation of the economic, cultural and social costs of industrial longline fishing in the Pacific and the benefits of sustainable use marine protected areas”, Marine Policy Volume 30, Issue 6, November 2006, Pages 809–820, EBSCO) Longlines are also one of the main threats to the survival of sharks and billfish. Recent studies have documented the rapid decline of large predatory fish species such as billfish, sharks and tuna. In the Pacific, the biomass of large predatory fish caught by longline fishing, for example, has declined by 90% since 1950 [7]. Earlier this year, the US warned that albacore and bigeye tuna, also caught with longlines, are being overfished in the Pacific. The problem is not restricted to the Pacific. A recent report has found that industrial longline fishing has contributed to the decline of oceanic whitetip and silky shark species by 90–99% in the Gulf of Mexico [8]. Another scientific study showed that in the Atlantic “large predatory fish biomass today is only about 10% of pre-industrial levels [9].” Seabirds I/LSea birds, especially albatross, are being killed off by longline fishingOvetz 2006 (Robert, Professor Robert Ovetz from College of Marin: Kentfield Kentfield, CA. and Sea Turtle Restoration Project, “The bottom line: An investigation of the economic, cultural and social costs of industrial longline fishing in the Pacific and the benefits of sustainable use marine protected areas”, Marine Policy Volume 30, Issue 6, November 2006, Pages 809–820, EBSCO) Longlines are also a significant threat to species of seabirds that are often caught on longline hooks on the high seas. Reports have documented that longline fishing is one of the main threats to the survival of the highly endangered Black-footed albatross in the Pacific. The latest estimates indicate that between 5000 and 13,800 Black-footed Albatross (1.9–5% of the population) are killed each year by industrial longline fishers with additional birds killed by other types of fishing and pollution [10] and [11].3 According to a recent report, 19 of the 21 species of albatross are now considered globally threatened with the remainder classified as near threatened [12]. Longlines are the most significant threat to these species’ survival. SolvencyCatch shares solve for detrimental long line fishingLevy 2010 (Sharon, freelance science writer and author of Once and Future Giants: What Ice Age Extinctions Tell Us about the Fate of Earth's Largest Animals, “Catch Shares Management”, BioScience, Vol. 60, No. 10 (November 2010), pp. 780-785, Jstor) The Alaskan halibut fishery in the early 1990s was an intense, adrenaline-soaked sprint. Fishing was permitted during just a few 24-hour windows. Two thousand boats might race to sea at once, each crew working madly to land a full year's catch in a day. Boats were overloaded with fish, and lives were lost: Nine workers drowned during derby fishing in Alaska during 1991 and 1992. In their hurry, fishers damaged creatures they were not targeting and lost much of their long-line gear, leaving thousands of baited hooks on the seafloor that imperiled halibut and other fish after the season had ended. When the catch was landed, the market was flooded with a year's worth of halibut at once, reducing its value. Then, in 1995, regulators abruptly ended the race for Alaskan halibut. The season expanded to months instead of days, and the value of the catch rose as fishers landed a steady supply of fresh halibut. Fishing accidents and fatalities dropped sharply. All of this was accomplished using a management system called individual transferable quotas (ITQs), a form of catch shares management under which individual fishers or associations are given rights to a set percentage of the total catch.
(Reese, recipient of the Presidents Distinguished Service Award from Humboldt State University for his inimitable leadership in conservation biology, an Outstanding Environmental Awareness Achievement Award Special to The StarPhoenix, “Oceans require conservation plan”, The Star Phoenix (Saskatoon, Saskatchewan), March 26, 2010 Friday, Lexis nexis) As a result, all known commercial deep-sea fish populations have fallen to around 20 per cent of the 1970s levels. One of the most prized and rare fish left on the globe is the bluefin tuna. It accelerates faster than a Ferrari and warms its blood through an ingenious heat exchange system. Eastern Atlantic bluefin is an endangered species and western Atlantic bluefin is worse off; it's listed as critically endangered. The FAO estimates that there are about 1,556 long-line fishing vessels of a freezing capacity larger than 90 tonnes catching tuna around the world. At 3.6 million tonnes of tuna harvested annually, the populations are all set to crash. Conserving the oceans' resources are clearly the only way forward in this century. An innovative, sustainable approach to harvesting fish in Iceland and elsewhere is that of individual transferable quotas that enable boats to own shares of an overall quota determined by scientists.
(JOE and MARK, Professor & Eminent Scholar; Department of Biological Sciences at Old Dominion University, “How the East Coast fishery is being dragged down EAST COAST"It is crucial that we review the way fish are caught - by towing nets (dragging) or using lines baited with many hooks (longlining). By not addressing the issue in a frank and public manner, we will only prolong the collapse of Canada's groundfishery”, The Globe and Mail (Canada), April 13, 1993 Tuesday, Lexis nexis) HOW have we been catching Canadian groundfish? The dominant methods are dragging (towing a net) and longlining (a long line of baited hooks). Over the past four decades, draggers have been taking an increasing proportion of the catch. Their reported landings are now 70 per cent of the total. Let's go to sea and observe the impact of these two gear types on the now much-depleted stocks. Out on Brown's Bank, a once-prime fishing ground off Nova Scotia, the dragger tows a funnel-shaped net with its heavy doors and rollers plowing and bouncing across the bottom. Marine organisms are damaged and killed, while a stream of sediment flows down-current. After a couple of hours of coffee and skippers' talk on the VHF radio, the net is hauled aboard and dumped. It is put out again and the culling begins. The undersized fish and "trash" (non-commercial species) go over the side dead. If the crew is highgrading, good but cheaper species follow them over the rail. The dragger searches out schools of fish with its sounder (fish finder) before setting its gear. Often its net doesn't even go in the water until the skipper "sees" a good bunch of fish. Thus, because it does not waste time and effort towing its net futilely, it can operate at a profit even while it further damages the dangerously low stocks. Dragging those trawl doors through the mud and over the rocks burns a lot of imported fuel, but the trip is still a moneymaker. NOT far away, on another boat, a "longline" is passing through a chute and over the stern. The thousands of hooks attached to this line are baited with baitfish caught by Maritimers. After the anchor is set it's time for a mug-up. One or two hours rest and the hauling begins. The few fish that are caught are now mostly small; "steakers" are scarce. Some "junk," such as dogfish, go over the side. "Can't make money this way any more, maybe it's time to quit." Longlining is a passive technology: The gear is set on likely bottom (good fish habitat, whether or not there are fish), relying on the fish to approach it and take the bait. As one study concluded, "The longliner fleet could be left essentially unregulated, since it is not economical for it to overfish the stock." Therefore, much costly enforcement can be avoided. There are other benefits as well, such as improved product quality and more long-term jobs. Longlining groundfish makes bottom-line sense for the fish, the fishers and the taxpayer. It is the best way to land fishsticks on North American tables. Conclusion: Our groundfish draggers should be converted to longliners. Unfortunately, that's not what we're doing. FOR some time now, at the urging of certain economists and corporate promoters, the Fisheries Minister and his advisers have been implementing a strategy to privatize Canada's marine resources. They define the overfishing by the draggers as an overcapacity problem, and say the institution of an individual transferable quota (ITQ) system will deal with this problem. ITQs are a radical change for fisheries management. Traditionally, an overall quota is set for a stock and it is competitively fished. Under the ITQ system, each boat is assigned a piece of the overall quota which it can fish, sell or rent. The idea is that quota pieces will be combined, to eliminate many players and ensure that the ones left will be profitable. Nice theory Directory: wp-content -> uploads -> 2014 2014 -> For want of a nail 2014 -> Stop Militarizing Law Enforcement Act of 2014 2014 -> Ihbb asian Championships 2014 middle school bowl Round 4 First Quarter 2014 -> Ihbb european Championships 2014 Bowl Round 4 First Quarter 2014 -> International History Bee and Bowl 2013-14 Asian Division Question Set Bowl Round Six 2014 -> United states patent and trademark office 2014 -> Coffs harbour eisteddfod vocal syllabus 2014 -> Listen News Programs Schedule pledge now 2014 -> Slow club announce third album complete surrender Download 0.57 Mb. Share with your friends:
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