Weak Hooks are a variant of Circle Hooks. They are made out of a lower-gauge wire which allows them to bend and straighten more easily than standard hooks, allowing large animals to escape but retaining target catch. Although in an early stage of research, weak hooks have been trialled in Hawwaiin longline pelagic fisheries to combat bycatch of false killer whales.
Current research centres around reducing bycatch from depredation in longline pelagic fisheries and is complemented by studies analysing the impacts of various hook strengths on toothed whale tissue and mandibles. Such research suggests that using circle hooks with a maximum wire diameter of 4.5mm, offset at 10 degrees or less, significantly improves the selectivity (for the target catch) of deep set longline fisheries. As of December 2012, their use is mandatory in Hawaii deep-set longline fisheries.
This page was last updated on 12.02.21.
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