A comparison of circle hook and J hook performance in a western equatorial Atlantic Ocean pelagic longline fishery

  • Published source details Pacheco J.C., Kerstetter D.W., Hazin F.H., Hazin H., Segundo R.S.S.L., Graves J.E., Carvalho F. & Travassos P.E. (2011) A comparison of circle hook and J hook performance in a western equatorial Atlantic Ocean pelagic longline fishery. Fisheries Research, 107, 39-45.


This study is summarised as evidence for the following.

Action Category

Use a different hook type

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

    A replicated, controlled study in 2006–2007 in an area of pelagic water in the Atlantic Ocean, off Brazil (Pacheco et al. 2011) found that circle hooks caught fewer unwanted rays Myliobatiformes and sailfish Istiophorus platypterus compared to J hooks, and overall similar amounts of other target and non-target fish groups. Overall, circle hooks caught fewer rays (two species, mainly pelagic stingray Pteroplatytrygon violacea) than J hooks (circle: 21, J hook: 161). Catches of unwanted sailfish were also lower on circle hooks (2) than J hooks (10). Overall catches of three other species groups (billfish Istiophoridae, other bony fish and sharks) and total catch composition were similar for each hook type (data reported as statistical model results). The occurrence of deep-hooking injuries (associated with higher post-release mortality) was lower on circle hooks than J hooks for all species groups (data reported as graphical analysis). In addition, target catches of tunas Thunnus spp. were higher on circle (29/1,000 hooks) than J hooks (23/1,000 hooks), but swordfish Xiphias gladius catches were similar. Data were collected during six pelagic longline trips using three vessels in August 2006 and January 2007. A total of 81 longline sets were fished (50,170 hooks) with circle hooks (size 18/0, 0° offset) alternated equally with J hooks (size 9/0, 10° offset) baited with squid Illex sp.

    (Summarised by: Leo Clarke)

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