Circle hooks: developing better fishing practices in the artisanal longline fisheries of the eastern Pacific Ocean

  • Published source details Andraka S., Mug M., Hall M., Pons M., Pacheco L., Parrales M., Rendón L., Parga M.L. & Mituhasi T. (2013) Circle hooks: developing better fishing practices in the artisanal longline fisheries of the eastern Pacific Ocean. Biological Conservation, 160, 214-224.


This study is summarised as evidence for the following.

Action Category

Use circle hooks instead of J-hooks

Action Link
Reptile Conservation
  1. Use circle hooks instead of J-hooks

    A replicated, controlled study in 2004–2010 in Ecuadorean, Panamanian and Costa Rican fisheries in the eastern Pacific Ocean (Andraka et al. 2013) found that unwanted catch of sea turtles was reduced when circle hooks were used instead of J-hooks in five artisanal surface longline fisheries. Unwanted catch of sea turtles was reduced when circle hooks were used compared to J-hooks in mahi mahi Coryphaena hippurus fisheries in Ecuador (circle: 1.3–1.6 turtles/1,000 hooks, J: 2.0–2.2) and Costa Rica (circle: 2.3, J: 2.9) and in combined tuna Thunnus albacares, billfish (Istiophoridae and Xiphiidae) and shark fisheries in Ecuador (circle: 0.6, J: 1.3), Costa Rica (circle: 0.4–1.5, J: 1.3–1.5) and Panama (circle: 0.9, J: 2.0). The effect on target fish species was mixed; in three comparisons circle hooks increased catch, in three they reduced catch and in one there was no difference (see original paper for details). A voluntary program to test use of circle hooks instead of traditional J-hooks began in the Eastern Pacific Ocean in 2004. Unwanted catch of sea turtles was compared between circle hooks (sizes: 14/0–18/0) and traditional J-hooks (J-style or tuna) in mahi mahi fisheries (Ecuador: 2 fisheries; Costa Rica: 1 fishery) and combined tuna, billfish and shark fisheries (Ecuador: 1 fishery; Panama: 1 fishery; Costa Rica: 2 fisheries). Hook sizes, baits, vessels and longline materials varied between fisheries (see original paper). Hook types were placed alternately along the long lines. A total of 3,126 longline deployments were made (328,523 total J-hooks; 401,839 total circle hooks).

    (Summarised by: Maggie Watson, Katie Sainsbury)

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