Catch rate and at‐vessel mortality of circle hooks versus J‐hooks in pelagic longline fisheries: a global meta‐analysis

  • Published source details Reinhardt J.F., Weaver J., Latham P.J., Dell'Apa A., Serafy J.E., Browder J.A., Christman M., Foster D.G. & Blankinship D.R. (2018) Catch rate and at‐vessel mortality of circle hooks versus J‐hooks in pelagic longline fisheries: a global meta‐analysis. Fish and Fisheries, 19, 413-430.


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 systematic review in 2018 of 42 studies of the effects of hook type in pelagic longline fisheries worldwide (Atlantic and Pacific Oceans) (Reinhardt et al. 2018) found that using circle hooks instead of conventional J-style hooks did not reduce catch rates of unwanted sharks (Selachii), and did not typically reduce the mortality of most sharks upon gear retrieval. Data were reported as statistical results – see original paper. There was no difference between hook types in catch rates of seven of 13 species, whilst catch rates of six of 13 unwanted shark species were higher on circle hooks than on J hooks. Mortality upon gear retrieval was lower for three of ten shark species on circle hooks than J hooks, and similar for seven species. Catches of target tuna Thunnus spp., billfishes Istiophoridae and swordfish Xiphiidae were higher on circle hooks than J hooks in five of 13 cases and lower in two cases. The systematic review summarized the effects of using circle hooks in longline fisheries compared to conventional J hooks on catch rates and at-vessel mortality during gear retrieval from 42 studies.

    (Summarised by: Leo Clarke)

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