How Much Does Swordfish Cost

Type of fishing net

Gillnetting is a fishing method that uses gillnets: vertical panels of netting that hang from a line with regularly spaced floaters that hold the line on the surface of the water. The floats are sometimes chosen "corks" and the line with corks is generally referred to every bit a "cork line." The line along the lesser of the panels is generally weighted. Traditionally this line has been weighted with lead and may be referred to every bit "lead line." A gillnet is unremarkably set in a directly line. Gillnets can be characterized past mesh size, as well as colour and type of filament from which they are made. Fish may be defenseless by gillnets in iii means:

1. Wedged – held by the mesh effectually the torso.
2. Gilled – held by mesh slipping backside the opercula.
3. Tangled – held by teeth, spines, maxillaries, or other protrusions without the body penetrating the mesh.

Most often fish are gilled. A fish swims into a cyberspace and passes only part style through the mesh. When it struggles to free itself, the twine slips behind the gill comprehend and prevents escape.^[1]

Gillnets are so effective that their use is closely monitored and regulated by fisheries direction and enforcement agencies. Mesh size, twine forcefulness, as well as net length and depth are all closely regulated to reduce bycatch of non-target species. Gillnets accept a loftier degree of size selectivity. Most salmon fisheries in particular have an extremely low incidence of catching non-target species.^[2]

Contemporary Canadian commercial salmon bowpicker on trailer. Gillnet is evident on the metallic drum in the bow of the gunkhole.

A angling vessel rigged to fish by gillnetting is a gillnetter. A gillnetter which deploys its gillnet from the bow is a bowpicker, while one which deploys its gillnet from the stern is a sternpicker. Gillnets differ from seines in that the latter uses a tighter weave to trap fish in an enclosed space, rather than directly communicable the fish every bit in a gillnet.

History [edit]

Gillnets existed in ancient times, every bit archaeological evidence from the Middle East demonstrates.^[iii] In Due north America, Native American fishermen used cedar canoes and natural fibre nets, e.g., made with nettles or the inner bark of cedar.^[four] They would attach stones to the bottom of the nets as weights, and pieces of wood to the top, to use as floats. This allowed the net to suspend straight up and down in the water. Each internet would be suspended either from shore or betwixt two boats. Native fishers in the Pacific Northwest, Canada, and Alaska nevertheless commonly use gillnets in their fisheries for salmon and steelhead.

Both drift gillnets and setnets have long been used by cultures around the world. In that location is testify of fisheries exploitation, including gillnetting, going far back in Japanese history, with many specific details available from the Edo period (1603–1868).^[5] Fisheries in the Shetland Islands, which were settled by Norsemen during the Viking Age, share cultural and technological similarities with Norwegian fisheries, including gillnet fisheries for herring.^[6] Many of the Norwegian immigrant fishermen who came to fish in the not bad Columbia River salmon fishery during the second half of the 19th century did so because they had experience in the gillnet fishery for cod in the waters surrounding the Lofoten Islands of northern Norway.^[7] Gillnets were used equally part of the seasonal round by Swedish fishermen besides.^[8] Welsh and English language fishermen gillnetted for Atlantic salmon in the rivers of Wales and England in coracles, using hand-made nets, for at to the lowest degree several centuries.^[9] These are only a few of the examples of historic gillnet fisheries around the world.

Gillnetting was an early fishing technology in colonial America,^{[ vague ]} used for instance, in fisheries for Atlantic salmon and shad.^[10] Immigrant fishermen from northern Europe and the Mediterranean brought a number of different adaptations of the applied science from their respective homelands with them to the rapidly expanding salmon fisheries of the Columbia River from the 1860s onward.^[11] The boats used by these fisherman were typically around 25 feet (8 m) long and powered by oars. Many of these boats also had small sails and were called "row-sail" boats. At the beginning of the 1900s, steam powered ships would haul these smaller boats to their angling grounds and retrieve them at the end of each day. Notwithstanding, at that fourth dimension gas powered boats were beginning to make their advent, and by the 1930s, the row-canvass boat had virtually disappeared, except in Bristol Bay, Alaska, where motors were prohibited in the gillnet fishery by territorial law until 1951.^[12]

In 1931, the starting time powered drum was created by Laurie Jarelainen.^{[ citation needed ]} The drum is a circular device that is set to the side of the boat and draws in the nets. The powered drum allowed the nets to be fatigued in much faster and along with the faster gas powered boats, fisherman were able to fish in areas they had previously been unable to go into, thereby revolutionizing the fishing industry.

During World State of war Two, navigation and communication devices, as well as many other forms of maritime equipment (ex. depth-sounding and radar) were improved and made more compact. These devices became much more accessible to the average fisherman, thus making their range and mobility increasingly larger. Information technology also served to brand the industry much more competitive, as the fisherman were forced to invest more than in boats and equipment to stay current with developing technology.

The introduction of fine synthetic fibres such as nylon in the structure of fishing gear during the 1960s marked an expansion in the commercial apply of gillnets. The new materials were cheaper and easier to handle, lasted longer and required less maintenance than natural fibres. In addition, multifilament nylon, monofilament or multimonofilament fibres become almost invisible in water, so nets made with synthetic twines generally caught greater numbers of fish than natural fibre nets used in comparable situations.

Nylon is highly resistant to abrasion and degradation, hence the netting has the potential to concluding for many years if it is not recovered. This ghost angling is of environmental business. Attaching the gillnet floats with biodegradable material tin can reduce the problem.^[xiii] Even so it is difficult to generalize virtually the longevity of ghost-fishing gillnets due to the varying environments in which they are used. Some researchers have found gill-nets still catching fish and crustaceans over a year after loss^[1], while others take found lost nets destroyed past moving ridge action inside one month^[2] or overgrown with seaweeds, increasing their visibility and reducing their catching potential to such an extent that they became a microhabitat used by small fish.^[3]

This type of net was heavily used by many Japanese, South Korean, and Taiwanese angling fleets on the high seas in the 1980s to target tunas. Although highly selective with respect to size class of animals captured, gillnets are associated with high numbers of incidental captures of cetaceans (whales and dolphins). In the Sri Lankan gillnet fishery, i dolphin is caught for every ane.7–4.0 tonnes of tuna landed^[4]. This compares poorly with the charge per unit of one dolphin per 70 tonnes of tuna landed in the eastern Pacific bag seine tuna fishery.

Many types of gillnets are used by fisheries scientists to monitor fish populations.^[fourteen] Vertical gillnets are designed to allow scientists to decide the depth distribution of the captured fish.^[15]

Legal status [edit]

United Nations Full general Assembly Resolution 46/215^[sixteen] called for the cessation of all "large-calibration pelagic drift-net fishing" in international waters past the end of 1992. The laws of individual countries vary with regard to fishing in waters under their jurisdiction.

Possession of gillnets is illegal in some U.S. states and heavily regulated in others.

Oregon voters had the chance to decide on whether gillnetting will continue in the Columbia River in Nov 2012 by voting on Measure 81.^[17] The measure was defeated with 65% of Oregon voters voting against the measure out and assuasive commercial gillnet fishing to keep on the Columbia River.^[eighteen]

The Columbia River Basin is currently under a direction understanding that spans from 2008 to December 31, 2017.^[19] This management agreement looks to get together information on fish harvesting through means including gillnets.^[20] The parties involved will convene once more to decide on further action after the current agreement ends.

The gill-netting season in Minnesota can vary from county to county and the internet types used are regulated on a lake past lake basis by the Minnesota Section of Natural Resources.^[21]

Virginia's gill-netting season is regulated by the Virginia Marine Resources Commission. During unlike months of the year, certain rivers have restricted mesh sizes, which vary by location.^[22]

There accept been proposed regulations to shut downwards drift gillnet fisheries whose by-grab numbers (which include dolphins, sea turtles and other marine life) were also high. In 2014, California lawmakers pushed for the banning of gillnet fishing through letters to federal line-fishing companies.^[23] The progress for these regulations accept been paused in California mid 2017.^[24]

Co-ordinate to the High Seas Fishing Compliance Act from 1996, a permit is require for all commercial fishing vessels that are registered in the United States and nether this act, vessels must have a tape of all their fishing efforts on the loftier seas.^[25]

Equally of November 2017, there has been a bill introduced to ameliorate the direction of driftnets, with gillnets being under the umbrella of this fishing tool.^[26] The pecker's focus is to ban the employ of big-scale nets while supporting the apply of alternative methods of fishing to decrease the maximum amount of bycatch. At that place is as well a bounty plan proposed in the bill for fishery participants who cease using big-calibration nets.^[26]

Selectivity [edit]

Selectivity properties of a gillnet on a hypothetical population

Gillnets are a series of panels of meshes with a weighted "pes rope" along the bottom, and a headline, to which floats are attached. By altering the ratio of floats to weights, buoyancy changes,^[27] and the net can therefore exist set to fish at whatever depth in the water column. In commercial fisheries, the meshes of a gillnet are uniform in size and shape. Fish smaller than the mesh of the internet laissez passer through unhindered, while those too large to push their heads through the meshes as far equally their gills are not retained. This gives gillnets the ability to target a specific size of fish, unlike other net gears such equally trawls, in which smaller fish pass through the meshes and all larger fish are captured in the net^[5].

Salmon [edit]

Commercial gillnet fisheries are still an of import method of harvesting salmon in Alaska, British Columbia, Washington, and Oregon. In the lower Columbia River, not-Indian commercial salmon fisheries for spring Chinook have developed methods of selectively harvesting adipose fin clipped hatchery salmon using minor mesh gillnets known as tangle nets or tooth nets. Non-adipose fin clipped fish (primarily natural origin salmon) must be released.^[28] Fishery direction agencies estimate a relatively depression release mortality rate on salmon and steelhead released from these small mesh gillnets.

Problems that tin arise from selective harvesting are smaller reproducing developed fish, also equally the unexpected mortality of the fish which sustain injuries from the gillnet but are non retained in the fishery. Most salmon populations include several historic period classes, allowing for fish of unlike ages, and sizes, to reproduce with each other. A recent 2009 written report looked at 59 years of catch and escapement data of Bristol Bay sockeye salmon to determine age and size at maturity trends attributable to the selectivity of commercial gillnet harvests. The study institute that the larger females (>550 mm) of all age classes were well-nigh susceptible to harvest.^[29] The study suggests that smaller, younger fish were more likely to successfully traverse the gillnet fishery and reproduce than the larger fish. The report as well found that the average length of sockeye harvested from 1946 to 2005 was viii mm larger than the sockeye who escaped the gillnet fishery to spawn, reducing the fecundity of the average female past 5%, or 104 eggs.^[29] If a salmon enters a gillnet, merely manages to escape, it can sustain injuries. These injuries can lead to a lower degree of reproductive success. A study aimed at quantifying mortality of Bristol Bay sockeye salmon due to gillnet-related injuries found that 11–29% of sockeye sustained fishery-related injuries owing to gillnets, and 51% of those fish were expected to non reproduce.^[30]

Gillnets are sometimes a controversial gear type particularly among sport fishers who fence they are inappropriate especially for salmon fisheries. These arguments are ofttimes related to allotment bug between commercial and recreational (sport) fisheries and not conservation bug.^[31] Most salmon fisheries, peculiarly those targeting Pacific salmon in North America, are strictly managed to minimize total impacts to specific populations and salmon fishery managers go along to allow the use of gillnets in these fisheries.^[32]

In 2012, Academy of Washington Fisheries Professor Emeritus Stephen Mathews compared Puget Sound bycatch data for the non-treaty gillnet and purse seine keta salmon fisheries. He found that although neither fishery had major bycatch issues with nontarget salmonids, the gillnet fishery has substantially less impact on nontarget Chinook salmon. His fulltext report is available from the Washington Country Puget Sound Salmon Commission.

Swordfish [edit]

Gillnets are also used out in the deep sea for fisheries whose master catch is swordfish. California driftnet fisheries have some of the highest rates of past-catch with 12 percent of the catch being the targeted swordfish while up to 68 percent of the catch being by-catch that will exist tossed dorsum to bounding main.^[24]

Alternatives [edit]

Given the selective properties of gillnet line-fishing, culling methods of harvest are currently being studied. Recent WDF&W reports suggest that bag seine is the most productive method with having highest grab per unit effort (CPUE), only has trivial information on the effectiveness of selectively harvesting hatchery-reared salmon.^[33] More conclusive research has been conducted jointly between the Confederated Tribes of the Colville Reservation and Bonneville Power Administration on a 10-yr study on selective harvest methods of hatchery origin salmon in the Upper Columbia River past purse seine and tangle net. Their 2009 and 2010 findings show that bag seines have a college pct of survivability and college CPUE than does tangle nets.^[34] A Colville Tribe biologist reports that during these 2 years the tribe harvested 3,163 hatchery Chinook while releasing 2,346 wild Chinook with simply one.4% direct or immediate mortality using handbag seines,^[35] whereas the tangle net was far less productive but had an estimate 12.5% mortality. Researchers commented that the use of recovery boxes and shortened periods between checking the nets would have likely decreased bloodshed rates. While there is information that shows success of selective methods of harvest at protecting wild and ESA listed salmon, there however must exist social acceptance of new methods of angling.

There have also been studies done to see if differing strategies could potentially decrease the estimated 400,000 almanac avian by-catch in littoral fisheries. These include three strategies that have a possible reduction in upwardly to 75% of avian by-catch: gear modifications, where visual devices will be placed near the top of the net so birds will be able to see the nets; affluence-based fishery openings, where of birds will decide whether the nets volition exist set up out or not; and time-of-day restrictions, which goes along with abundance- where bird past catch tended to occur at dawn and dusk, where as fish take hold of occurred mostly at dawn.^[36]

For marine mammal by-take hold of, field experiments have shown that the use of pingers on nets resulted in significantly lower numbers of by-catch than nets without pingers. Later this study was completed by Jay Barlow, it was adamant that there would be a 12-fold decrease in short-beaked mutual dolphins defenseless, a 4-fold decrease in other cetaceans and a iii-fold decrease in pinnipeds for nets containing pingers.^[37]

Types of gillnets [edit]

The FAO classifies gillnet gear types as follows:

Set gillnets [edit]

Set gillnets consist of a single netting wall kept vertical by a floatline (upper line/headrope) and a weighted groundline (lower line/footrope). Small floats, usually shaped like eggs or cylinders and made of solid plastic, are evenly distributed along the floatline, while lead weights are evenly distributed along groundline. The lower line can likewise be fabricated of pb cored rope, which does non need additional weight. The cyberspace is set on the lesser, or at a distance above it and held in place with anchors or weights on both ends. By adjusting the pattern these nets can fish in surface layers, in mid water or at the lesser, targeting pelagic, demersal or benthic species. On small boats gillnets are handled by hand. Larger boats use hydraulic net haulers or net drums. Set gillnets are widely used all over the world, and are employed both in inland and sea waters. They are popular with artisanal fisheries because no specialized gear is needed, and it is low toll based on the relationship of fuel/fish.^[13]

Encircling gillnets [edit]

Encircling gillnets are gillnets set vertically in shallow water, with the floatline remaining at the surface and then they encircle fish. Small open up boats or canoes can be used to set the net around the fish. Once the fish are encircled, the fishers shout and splash the water to panic the fish and so they gill or entangle themselves. In that location is little negative impact on the surround.^[38] Every bit soon as the gear is gear up the scaring takes place and the net is hauled back in. The fish are live and discards tin exist returned to the sea. Encircling gillnets are commonly used by groups of small-scale fishers, and does not require other equipment.^[38]

Combined gillnets-trammel nets [edit]

This lesser-set up gear has two parts:

• the upper part is a standard gillnet where semi-demersal or pelagic fish can be gilled
• the lower part is a trammel internet where bottom fish can entangle.

The combined nets are maintained more or less vertically in the usual way by floats on the floatline and weights on the groundline. They are set on the bottom. After a fourth dimension depending on the target species, they are hauled on board. Traditional combined nets were hauled by manus, especially on smaller boats. Recent hydraulic driven net haulers are at present common. The gilled, entangled and enmeshed fish are removed from the net by hand. Of some business organization with this method is ghost fishing by lost nets and bycatch of diving seabirds. Nets combined in this way were first used in the Mediterranean.^[39]

Drift nets [edit]

A drift net consists of one or more panels of webbing fastened together. They are left costless to drift with the current, usually virtually the surface or non far beneath it. Floats on the floatline and weights on the groundline keep them vertical. Migrate nets migrate with the current while they are continued with the operating vessel, the driftnetter or drifter.

Migrate nets are usually used to grab schooling forage fish such as herring and sardines, and likewise larger pelagic fish such as tuna, salmon and pelagic squid. Net haulers are usually used to set and haul driftnets, with a out-of-stater capstan on the forepart of the vessel. In developing countries most nets are hauled by hand. The mesh size of the gillnets is very constructive at selecting or regulating the size of fish caught. The drift cyberspace has a low fuel/fish energy consumption compared to other line-fishing gear. Withal, the result of concern with this blazon of net is the bycatch of species that are not targeted, such as marine mammals, seabirds and to a modest extent turtles. The use of drift nets longer than 2.5 kilometres on the high seas was banned past the United nations in 1991. Prior to this ban, drift nets were reaching lengths of 60 kilometres. However, there are still serious concerns with ongoing violations.^[xl]

Gillnets and entangling nets [edit]

The tangle net, or tooth net, originated in British Columbia, Canada, equally a gear specifically developed for selective fisheries.^[41] Tangle nets accept smaller mesh sizes than standard gillnets. They are designed to catch fish past their olfactory organ or jaw, enabling bycatch to be resuscitated and released unharmed. Tangle nets as adapted to the marker-selective fishery for leap Chinook salmon on the lower Columbia River have a standard mesh size of iv+ 1⁄four inches (eleven cm). Short net lengths and soak times are used in an endeavor to land fish in good condition. Tangle nets are typically used in situations where the release of certain (ordinarily wild) fish unharmed is desirable. In a typical situation calling for the use of a tangle internet, for instance, all fish retaining their adipose fins (ordinarily wild) must be returned to the water. Tangle nets are used in conjunction with a live recovery box, which acts as a resuscitation chamber for unmarked fish that appear lethargic or stressed before their release into the h2o.^{[42] [43]}

Historical images [edit]

Salmon gillnet boat with drum

Repairing salmon gillnet

Hauling the gillnet over the ability-driven drum

Removing salmon from the gillnet

Notes [edit]

1. ^ White potato, B.; Willis, D. (1996). Fisheries Techniques (2d ed.). Bethesda, Md: American Fisheries Society. Archived from the original on 2013-02-21.
2. ^ Selective Fisheries (PDF) (Report). Oregon Department of Fish and Wildlife. Archived from the original (PDF) on 2016-03-03. Retrieved 26 September 2014.
3. ^ Nun, Mendel (1989). The Body of water of Galilee and Its Fishermen in the New Attestation, pp. 28–44. Kibbutz Ein Gev, Kinnereth Sailing Co.
4. ^ Stewart, Hilary (1977). Indian Angling: Early on Methods on the Northwest Coast, p.79 in 1st paperback edition, 1982. Seattle, Academy of Washington Press.
5. ^ Ruddle, Kenneth and Akimich, Tomoya. "Ocean Tenure in Nippon and the Southwestern Ryukyus," in Cordell, John, Ed. (1989), A Sea of Small Boats, pp. 337–370. Cambridge, Mass., Cultural Survival, Inc.
6. ^ Goodlad, C.A. (1970). Shetland Angling Saga, pp. 59–60. The Shetland Times, Ltd.
7. ^ Martin, Irene (1994). Legacy and Testament: The Story of the Columbia River Gillnetter, p. 38. Pullman, Washington Land University Press.
8. ^ Lofgen, Ovar. "Marine Ecotypes in Preindustrial Sweden: A Comparative Give-and-take of Swedish Peasant Fishermen," in Andersen, Raoul, Ed. (1979), Due north Atlantic Maritime Cultures, pp. 83–109. The Hague, Mouton.
9. ^ Jenkins, J. Geraint (1974). Nets and Coracles, p. 68. London, David and Charles.
10. ^ Netboy, Anthony (1973) The Salmon: Their Fight for Survival, pp. 181–182. Boston, Houghton Mifflin.
11. ^ Martin, 1994, p. 44.
12. ^ Andrews, Ralph W. and Larsen, A.K. (1959). Fish and Ships, p. 108. Seattle, Superior Publishing Co.
13. ^ ^{a b} FAO: Fishing Gear Types: Gillnets
14. ^ Crawford, Bruce (2007). "Variable Mesh Gill Nets (in Lakes)". In Johnson, David; et al. (eds.). Salmonid Field Protocols Handbook. Bethesda, Md: American Fisheries Society. pp. 425–433.
15. ^ Lackey, Robert (1968). "Vertical gill nets for studying depth distribution of small fish". Transactions of the American Fisheries Social club. 97 (3): 296–299. doi:10.1577/1548-8659(1968)97[296:VGNFSD]2.0.CO;ii.
16. ^ "A/RES/46/215. Big-scale pelagic drift-cyberspace angling and its bear upon on the living marine resources of the earth's oceans and seas". www.un.org . Retrieved 4 Apr 2018.
17. ^ "Yes on Measure 81 Stop Gillnetting". Archived from the original on 14 Baronial 2012. Retrieved fourteen August 2012.
18. ^ "Oregon Secretary of Land: Official Results November 2012 General Election". sos.oregon.gov . Retrieved iv Apr 2018.
19. ^ "Environmental Impact Statement for Programmatic Review of Harvest Deportment for Salmon and Steelhead in the Columbia Basin related to U.S. v. Oregon :: NOAA Fisheries W Declension Region". world wide web.westcoast.fisheries.noaa.gov. NOAA Fisheries Westward Coast Region. Retrieved xxx Nov 2017.
20. ^ "2008–2017 United States v. Oregon Direction Agreement May 2008" (PDF). U.Southward. Fish and Wildlife Service . Retrieved 30 November 2017.
21. ^ "Minnesota Gill Netting Regualtions" (PDF).
22. ^ "CHAPTER: PERTAINING TO THE SETTING AND MESH SIZE OF GILL NETS". www.mrc.country.va.us. Virginia Marine Resources Commission. Retrieved 30 November 2017.
23. ^ "California Lawmakers Call for Stop to the Utilize of Drift Gillnets off the Due west Declension". Oceana . Retrieved 30 November 2017.
24. ^ ^{a b} "Drift Gillnets in California". 2017.
25. ^ "NOAA Fisheries- W Coast Region". 2017.
26. ^ ^{a b} "Archived copy" (PDF). Archived from the original (PDF) on 2017-12-01. Retrieved 2017-11-30 . {{cite web}}: CS1 maint: archived copy equally championship (link)
27. ^ Martin 1994, pp. 52–57.
28. ^ http://wdfw.wa.gov/publications/01353/wdfw01353.pdf^{[ bare URL PDF ]}
29. ^ ^{a b} Kendall, Neala Westward, Jeffery J. Hard and Thomas P. Quinn. 2009. Quantifying Six Decades of Fishery Selection for Size and Age at Maturity in Sockeye Salmon. Evolutionary Applications. 523–536.
30. ^ Baker, Matthew R and Daniel E Schindler. 2009. Unaccounted Mortality in Salmon Fisheries: Non-retention in Gillnets and Effects on Estimates of Spawners. Periodical of Applied Environmental (46). 752–761.
31. ^ "Gillnet Ban Angers Fishers". Daily Astorian. 2012-12-13. Archived from the original on 2013-06-08. Retrieved 2013-01-06 .
32. ^ "Background - Pacific Fishery Management Quango". www.pcouncil.org . Retrieved iv April 2018.
33. ^ WDF&Due west. 2010. 2010 Alternative Gear Catch...
34. ^ Colville Tribe. 2011. Major Results...
35. ^ Rayton, Michael. 2010. Proclamation of Support...
36. ^ Melvin, Edward F. (Dec 1999). "Novel Tools to Reduce Seabird Bycatch in Littoral Gillnet Fisheries". Conservation Biology. thirteen (vi): 1386–1397. doi:10.1046/j.1523-1739.1999.98426.x. S2CID 86638654.
37. ^ Barlow, Jay (April 2003). "Field Experiments Testify That Acoustic Pingers Reduce Marine Mammal Bycatch In The California Migrate Gill Internet Fishery". Marine Mammal Scientific discipline. xix (ii): 265–283. doi:ten.1111/j.1748-7692.2003.tb01108.10. S2CID 26969713.
38. ^ ^{a b} FAO: Fishing Gear Types: Gillnets
39. ^ FAO: Fishing Gear Types: Combined gillnets-trammel nets
40. ^ FAO: Fishing Gear Types: Driftnets
41. ^ Petrunia, William Mark (1997). "Tooth Net Fishery. Report on Scientific License 96.149." Jan. v, 1997.
42. ^ "A Sustainable Fishery". Salmon For All . Retrieved four April 2018.
43. ^ FAO: Fishing Gear Types: Gillnets and entangling nets

References [edit]

1. ^ Erzini, K. Monteiro, C., Ribeiro, J., Santos, K., Gaspar, M., Montiero, P. & Borges, T. (1997) An experimental report of "ghost-fishing" off the Algarve (southern Portugal). Marine Ecology Progress Serial 158:257–265.
2. ^ Hall, M.A. (1998) An ecological view of the tuna-dolphin problem: impacts and trade-offs. Reviews in Fish Biological science and Fisheries. 8:1–34.
3. ^ Kaiser, One thousand.J, Bullimore, B., Newman, P., Lock, K. & Gilbert, S. (1996) Catches in "ghost-fishing" set nets. Marine Ecology Progress Series. 145:xi–sixteen.
4. ^ Potter, Due east.C.E. & Pawson, M.G. (1991) Gill Netting. MAFF Fisheries Leaflet 69. [6]
5. ^ Puente, Due east. (1997) Incidental impacts of gill nets. Report to the European Commission, No. 94/095,152.

External links [edit]

Wikimedia Eatables has media related to Gillnets.

• Video: Gillnets in Operation
• Video: Gillnetting the Copper River Delta, Alaska
• Video: Tangle Cyberspace Angling on the Columbia River
• Manual on estimation of selectivity for gillnet and longline gears in abundance surveys - study for Food and Agriculture Organisation of the Un, 2000.
• http://www.seawatch.org/position_papers/gillnet.php Archived 2013-06-24 at the Wayback Machine
• Puget Sound Salmon Commission (WSDAg) bycatch report

How Much Does Swordfish Cost,

Source: https://en.wikipedia.org/wiki/Gillnetting

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