Size selection of whitefish (Coregonus maraena) in a pontoon trap equipped with an encircling square mesh selection panel

  • Published source details Lundin M., Calamnius L. & Fjälling A. (2015) Size selection of whitefish (Coregonus maraena) in a pontoon trap equipped with an encircling square mesh selection panel. Fisheries Research, 161, 330-335.


This study is summarised as evidence for the following.

Action Category

Modify fishing trap/pot configuration

Action Link
Marine Fish Conservation
  1. Modify fishing trap/pot configuration

    A replicated, controlled study in 2012 in an inshore area in the Bothnian Sea, Sweden (Lundin et al. 2015) found that a pontoon fish trap modified with a square mesh escape panel fitted in the fish chamber reduced the catches of immature whitefish Coregonus maraena compared to traps without a panel. The proportion of undersized (<30 cm) whitefish in catches was 9% in modified traps and 32% in unmodified traps. A total of 72% of the whitefish <30 cm was estimated to have escaped through the panel that would otherwise have been captured. The number of whitefish caught in the modified trap was lower (488 fish) than the unmodified trap (1,003 fish). Data were collected from 28 deployments (9 m depth) of two pontoon traps fished at the same time 800 m apart between June-August 2012. The fish chamber with and without a 50 × 50 mm square mesh panel were exchanged between traps every two weeks (four replicates). See original paper for trap specifications. Escaping fish were sampled by video cameras attached next to the panel.

    (Summarised by: Chris Barrett)

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