Introduction Demersal longlining is global Copyright 1999-2010
Michael Pidwirny
Slide 3
Objectives Define demersal longlining & describe 1
potential impact Describe 3 components of demersal longline gear
List 2 types of specialized equipment you may encounter Demonstrate
ability to complete the Gear Description form
Slide 4
What is demersal longlining? Hook & line gear uses bait to
attract fish in on or near bottom Usually on continental shelf or
slope Schoolmeester & Baker 2009
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What is demersal longlining? Hook & line gear uses bait to
attract fish on or near bottom Usually on continental shelf &
slope Primary targets: gadiiformes, sharks Cohen et al. 1990; FAO
via http://www.fishbase.org/
http://hawaii.gov/dlnr/dar/sharks/offshore.html
Slide 6
What is demersal longlining? Hook & line gear uses bait to
attract fish on or near bottom Usually on continental shelf &
slope Primary targets: gadoids, sharks Bait = fish or squid
depending on target
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What is demersal longlining? Hook & line gear uses bait to
attract fish on or near bottom Usually on continental shelf &
slope Primary targets: gadoids, sharks Bait = fish or squid
depending on target Fishery impacts bycatch of seabirds, sharks,
coral Nicolas Gasco F. Arocha Red snapper
http://forums.floridasportsman.com/forum/
west-central-general-info/6-month-grouper- closier-2011 Lophelia II
2009: Deepwater Coral Expedition: Reefs, Rigs, and Wrecks
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Data collection priorities 1. Estimate effort for each gear
deployment; 2. Identify every individual caught in subsample and
estimate percent retained; 3. Collect biological information on
target and other identified species as requested; 4. Record all
sightings and interactions with marine mammals and sea turtles; 5.
Record vessel and fishing gear characteristics.
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How is gear fished? Strategies
http://flowergarden.noaa.gov/image_library
/deepreefimages.html
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How is gear fished? Strategies Deployment (videos)
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How is gear fished? Strategies Deployment Retrieval Andy Murch,
http://sharkdiver.wordpress.com/ B. Richardson 2005 SEASWAP John
Bennett - http://sanaspiring.wordpress.com
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Gear components - overview Single line Double line
Occasionally deployed a single streamer. Streamer consisted of
50m of 3- strand blue polypropylene line with packing straps
inserted every 2 m. A small float (.3m diameter) was attached to
the terminal end.
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Summary Describe the difference between demersal &
semi-pelagic longlining What are the potential impacts of this
fishery? Describe 3 components of demersal longline gear List 2
types of specialized equipment you may encounter on demersal
longline vessels
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References Beverly, S. 2009. Longline terminal gear
Identification guide - Draft. Submitted to the Western and Central
Pacific Fisheries Commission, Scientific Committee, Fifth Regular
Session, 10-21 August 2009, Port Vila, Vanuatu,
WCPFC-SC5-2009/FT-IP-01, Secretariat of the Pacific Community,
Marine Resources Division, Coastal Fisheries Programme, Noumea
Cedex, New Caledonia. BirdLife International Bycatch Mitigation
Fact Sheet 11 (Version 1) BirdLife International Bycatch Mitigation
Fact Sheet 12 (Version 1) Cohen, D.M., T. Inada, T. Iwamoto and N.
Scialabba 1990 FAO Species Catalogue. Vol. 10. Gadiform fishes of
the world (Order Gadiformes). An annotated and illustrated
catalogue of cods, hakes, grenadiers and other gadiform fishes
known to date. FAO Fish. Synop. 10 (125). 442 p. Hanrahan, J., D.
J. Melindy, and J. V. Pelrine. 1997. At-sea Observer Program
Operations Manual: A Training Aid and Field Reference. National
At-sea Fisheries Observer Program, Department of Fisheries and
Oceans, Ottawa, Canada. Michael Pidwirny & Scott Jones.
1999-2010. Fundamentals of Physical Geography (2 nd Edition) (e-
book). University of British Columbia Okanagan.
http://www.physicalgeography.net/fundamentals/contents.html
Schoolmeester, Tina and Elaine Baker (eds) 2009. Continental Shelf:
The Last Maritime Zone. UNEP/GRID-Arendal, Norway.
http://www.unep.org/dewa/pdf/AoA/Continental_Shelf.pdf Tietze, U.;
Thiele, W.; Lasch, R.; Thomsen, B; Rihan, D. Economic performance
and fishing efficiency of marine capture fisheries. FAO Fisheries
Technical Paper. No. 482. Rome, FAO. 2005. 68p.
http://www.fao.org/docrep/008/y6982e/y6982e05.htm
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Misc photos http://www.frpboat.cn/fishing-2998.asp
http://www.ecplaza.net/search/0s1nf20sell/tuna_longline_fishing_vessel.html
Cuban longline vessel: FAO Western Central Atlantic Fishery
Commission. 2002