Gear Technology
Gear Efficiency Workshop for Fishermen
A free workshop aimed for vessel operators and skippers in the inshore trawl fisheries around New Zealand took place on 29 May 2008. The workshop aimed to shape the direction of the gear and operations efficiency project by Ulrik Hansen.
Ulrik Hansen was a visiting fishing gear scientist from the SINTEF North Sea Centre Flume Tank Laboratory in Hirtshals, Denmark in 2008 and 2009. You can visit Ulrik's blog here »
Arkley, Ken: Fishing Trials to Evaluate the Performance of a Trawl, Constructed from T90 (turned mesh netting). SeaFish publication. 2008
This report describes a demonstration trial of a single-rig demersal whitefish 'Rockhopper' trawl constructed entirely of T90 or turned mesh netting. The aim of the trials was to evaluate the performance of T90 trawl with reference to fuel savings as a result of the reduced drag associated with this technology.
PDF version (3.9 MB) of Reducing Drag in Towed Fishing Gears can be downloaded on the Seafish website.
Revill, A: First results from a pilot study 'North Sea fishing trials using the Eliminator trawl.' 2007
This study reports on the first known testing of a new design of trawl gear in European waters. The trials indicate use of the new gear to selectively target haddock and whiting in a mixed demersal fishery reducing unwanted by-catch by 83% (inculding rays and gurnard).
Ward, N; Montgomerie, M; Lart, W: Fuel Efficiency trials using Jackson trawls with reduced twine diameter. Seafish publication, 2005
This is a report on sea trials in the North Sea undertaken to compare the drag of twin trawls of traditional polythene twines with new trawls of reduced twine diameters. The new trawls had a reduced drag compared with the old trawls and increased mouth opening.
WWF International Smart Gear Winners. Seafood New Zealand, December 2007
A team of inventors from Rhode Island won the fourth annual WWF International Smart Gear Competition for their invention the "Eliminator".Economic comparison of single-rig and twin-rig trawl for nephrops
Background and theory of twin-rig trawling, cost of converting from single-rig to twin-rig, including the economic implications.
PDF version (508 kB) can be downloaded on the Seafish website.
Twin Trawl Report, Crimond, 1996
A project which was carried out in 1996 to transfer twin trawl technology from Europe to the shrimp industry in Canada. The objectives of this project were to investigate if the introduction of this trawling technology would achieve the above described objectives of improved energy efficiency, effective conservation characteristics, and enhanced product quality.
The Twin Trawl Report can be found on the Crimond website.
Performance of a trawl codend made from 90ยบ turned netting (T90) compared with that of traditional codends
This paper by Ulrik Jes Hansen describes a series of tests conducted in the SINTEF Flume Tank with different designs and constructions of codends. The principal aim was to disclose the performance of a codend where part of the netting was turned 90° (called T90) and compare it with codends made from netting stretched in the normal direction. It is concluded that the T90 codend must be superior to standard codends in many ways: preservation of fish quality, selectivity, survival rate of escapees, efficiency and strength.
Commercial Fishing Trials of a Twin-Rig Trawling System Using a Two-Warp Arrangement MFV Cygnus Star
This report describes the follow-up work resulting from initial gear handling trials of a twin-trawl system using a two-warp arrangement.
PDF version (2 MB) can be downloaded on the Seafish website.
A demonstration of "Outrigger Trawling" in the SW of England on MFV Admiral Gordon
This report demonstrates an alternative fishing method commonly known as Outrigger trawling. This involved replacing the heavy beam trawls which are normally towed by the vessel with two demersal trawls, each trawl spread with its own set of trawl doors and towed from the derricks. This change alone will have a significant impact on bottom and gear drag and thereby reduce fuel consumption for increased profitability and a reduction in environmental impact.
Please contact the New Zealand Seafood Industry Council for a copy of this report.
Otterboard Performance and Behaviour
This Manual is based on results from a project between the Sea Fish Industry Authority (U.K.), IFREMER (France) and DIFTA (Denmark) to assess the performance of a wide range of otterboards which are available to fishermen.
Please contact the New Zealand Seafood Industry Council for a copy of this report.
Recent Trade Articles
Please contact the information centre for a copy of any of these articles.
info@seafood.co.nz or 04 385 4005.
Twenty years of Dyneema in fishing
NZ skipper proves long life of Dyneema
French doors 'cut fuel by 20%'
Magnet fuel treatment system 'returns investment in three months'
Gear course tailored for inshore fishermen
Double bosom nets 'slash fuel costs'
Conquest trawl conquers at Hirtshals tests
Twin-trawls cut fuel bill
Fishing News International, August 2007, p. 32
A Belgian fishing vessel which converted from beaming to twin-trawling has cut her fuel bill by a quarter.
Three metre downsize with Stealth doors
Fishing News International, March 2007, p. 30
New design of pelagic doors to keep low angle of attack, resistance to a minimum but still generate maximum spread and high lift provides benefit of reduced towing resistance and lower fuel costs.
Ground gear helps slash fishing time 'by one-fifth'
Fishing News International, March 2007, p. 28
Innovation with spreading ground gear to prevent fish loss under gear is resulting in greater catch efficiency and reduced towing time.
Stealth doors pass first sea trials
Fishing News International, August 2007, p. 34
First sea trials of new stealth doors by pelagic trawlers targetting southern blue whiting allowed the vessel to increase towing speed from 3.6 knots to 4 knots without using more fuel.
Hex-Mesh firm doubles size to meet demand
Fishing News International, September 2007, p. 38
Hexagonal meshes trailed in Northern hemisphere redfish fishery are showing potential for fuel savings.
Dyneema to boost catches and profits
World Fishing - December 07/January 08, p. 14
Promotes the use of polythene fibre instead of steel wire and traditional synthetics for operational and cost benefits.
Gear trial in France cuts cost of fuel
Fishing News International, January 2008, p. 10
A French study demonstrates that huge fuel savings are available by modifying fishing gear to cut drag. Use of thinner twines in the back of the belly and opting for smaller doors has shown 14% savings.
Demand grows for lighter trawls
Fishing News International, February 2008, p. 13
Discusses trends in more efficient trawl gear.