Sex- and size-selective harvesting of corkwing wrasse (Symphodus melops)—a cleaner fish used in salmonid aquaculture

  • Published source details Halvorsen K.T., Sørdalen T.K., Vøllestad L.A., Skiftesvik A.B., Espeland S.H. & Olsen E.M. (2017) Sex- and size-selective harvesting of corkwing wrasse (Symphodus melops)—a cleaner fish used in salmonid aquaculture. ICES Journal of Marine Science, 74, 660-669.


This study is summarised as evidence for the following.

Action Category

Cease or prohibit all types of fishing in a marine protected area

Action Link
Marine Fish Conservation
  1. Cease or prohibit all types of fishing in a marine protected area

    A site comparison study in 2014 at two rocky sites in a bay in the North Sea off western Norway (Halvorsen et al. 2017) found that the commercial fishing mortality of corkwing wrasse Symphodus melops originally tagged at a small temporary marine protected area where fishing is prohibited was reduced compared to wrasse tagged at a fished site, but there was a similar selective removal of fish by size and sex regardless of site of origin. Overall fishing mortality of wrasse tagged inside the no-fishing site was lower than wrasse tagged in a fished site (not fished: 6–9%, fished: 31–41%). However, fishing mortality of nesting male wrasse (not fished: 12–15%, fished: 36–49%) was higher than for females (not fished: 3–5%, fished: 29–36%) at both sites. Average total length of nesting males was 119–141 mm and females 131–136 mm. In 2014, a total of 1,057 corkwing wrasses were tagged during (May–June) and after (July) the spawning period: 492 within a temporary no-fishing site (600 m of coastline, duration of protection was not reported) and 565 in a nearby site with no fishing restrictions. Fishing mortality of tagged wrasse was determined by recording the numbers captured and retained on all commercial potting fishing trips occurring within the bay over a three-month period.

    (Summarised by: Natasha Taylor)

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