Study

Size-selective effects of increasing bait size by using an inedible body on longline hooks

  • Published source details Løkkeborg S. & Bjordal A. (1995) Size-selective effects of increasing bait size by using an inedible body on longline hooks. Fisheries Research, 24, 273-279.

Actions

This study is summarised as evidence for the following.

Action Category

Use a different bait type

Action Link
Marine Fish Conservation
  1. Use a different bait type

    A replicated, controlled study in 1990–1991 in two pelagic areas in the Norwegian/Barents Seas, off Norway (Løkkeborg & Bjordal 1995) found that bait on pelagic longlines that had been made to appear larger caught fewer small and undersized haddock Melanogrammus aeglefinus than bait of a standard, smaller size, but catches were similar for torsk Brosme brosme and ling Molva molva. When bait appeared larger, fewer small and undersized (<46 cm) haddock were caught (26 fish) than with standard sized bait (45 fish). However, catches of larger, legal sized (>46 cm) haddock were similar for each bait type (large: 67, standard: 74 fish). Total catch of torsk was similar between bait types, across all sizes (large: 173, standard: 160 fish) (no ling data presented.) In addition, the mean size of fish caught on experimental and standard baits was similar for torsk (54 vs 54 cm) and ling (91 vs 95 cm). Trials were carried out in November 1990 (western Norway, 120–370 m depth), and in July 1991 (northern Norway, 373–415 m depth). Experimental bait was made from a piece of plastic attached to the shank of a circle hook around which the bait was wrapped, giving it a larger appearance. Hooks were baited with mackerel (Scombridae) in western Norway, and mackerel and squid (Cephalopoda) in northern Norway. Hooks were left for 4–14 h in western Norway and 11–12 h in northern Norway. Detailed gear specifications are given in the original paper.

    (Summarised by: Chris Barrett)

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