Study

Hook shedding and post-release fate of deep-hooked European eel

  • Published source details Weltersbach M.S., Ferter K., Sambraus F. & Strehlow H.V. (2016) Hook shedding and post-release fate of deep-hooked European eel. Biological Conservation, 199, 16-24.

Actions

This study is summarised as evidence for the following.

Action Category

Change type of recreational fishing gear (e.g. hook type, bait, lure size)

Action Link
Eel Conservation in Inland Habitats
  1. Change type of recreational fishing gear (e.g. hook type, bait, lure size)

    A replicated, controlled study in 2014 in a lake in Hordaland, Norway (Weltersbach et al. 2018) found that using small hooks for recreational fishing of European eels Anguilla anguilla led to higher hook-shedding rates compared to large hooks, but survival rates were similar for eels caught on small and large hooks with and without barbs. Seven of 17 captured eels (41%) shed small hooks after release, whereas none of 15 eels (0%) shed large hooks. After five months, the percentage of released eels that survived did not differ significantly between those caught on large barbed (5 of 10 eels, 50%), large barbless (3 of 5 eels, 60%), small barbed (8 of 11 eels, 73%) or small barbless hooks (3 of 6 eels, 50%). In May 2014, thirty-two European eels (31–50 cm long) were caught by rod and line from a lake shoreline at night. Large (10-mm gap width) and small hooks (6.8-mm gap width) with and without barbs were attached to 7-kg monofilament line and baited with 1–2 live earthworms Eisenia hortensis. All captured eels were hooked beyond the mouth cavity (‘deep-hooked’), and the line cut as close to the mouth as possible. Eels were transported to a research facility where they were anaesthetized, measured, tagged and x-rayed before being transferred to a holding tank. Eels were fed and checked daily for 23 weeks, and x-rayed 1, 3, 10, 24, 54, 115 and 163 days after capture. 

    (Summarised by: Anna Berthinussen)

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