Study

Shark catch in a pelagic longline fishery: comparison of circle and tuna hooks

  • Published source details Yokota K., Kiyota M. & Minami H. (2006) Shark catch in a pelagic longline fishery: comparison of circle and tuna hooks. Fisheries Research, 81, 337-341.

Actions

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 2005 in an area of coastal, pelagic water in the western North Pacific, off Japan (Yokota et al. 2006) found that changing hook type and size to a circle hook from a standard hook did not reduce the unwanted catches, or capture mortality, of blue shark Prionace glauca in a longline fishery. Across both vessels, average blue shark catch rates were similar with larger hook sizes and different shape compared to the standard (largest: 36–94, intermediate: 38–95, standard: 41–82 sharks/1,000 hooks). Similarly, the proportion of dead individuals did not differ between hook types (data reported as statistical results). Data were collected on two research vessels from 52 fishing deployments between May–September 2005. A total of 900 hooks were used/longline deployment on one vessel and 960 hooks/longline for the other (all baited with Japanese common squid Todarodes pacificus). Blocks of 20 hooks of each of two test hook types (5.2 and 4.3 size circle hooks) and a standard Japanese hook type (3.8 size tuna hook) were fished in a repeating pattern on the longline. During hauling the species, number and condition of fish caught were recorded.

    (Summarised by: Chris Barrett)

Output references
What Works 2021 cover

What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

More about What Works in Conservation

Download free PDF or purchase
The Conservation Evidence Journal

The Conservation Evidence Journal

An online, free to publish in, open-access journal publishing results from research and projects that test the effectiveness of conservation actions.

Read the latest volume: Volume 21

Go to the CE Journal

Discover more on our blog

Our blog contains the latest news and updates from the Conservation Evidence team, the Conservation Evidence Journal, and our global partners in evidence-based conservation.


Who uses Conservation Evidence?

Meet some of the evidence champions

Endangered Landscape ProgrammeRed List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Mauritian Wildlife Supporting Conservation Leaders
Sustainability Dashboard National Biodiversity Network Frog Life The international journey of Conservation - Oryx Cool Farm Alliance UNEP AWFA Bat Conservation InternationalPeople trust for endangered species Vincet Wildlife Trust