• Can vertical separation of species in trawls be utilized to reduce bycatch in shrimp fisheries? 

      Larsen, Roger B.; Herrmann, Bent; Brcic, Jure; Sistiaga, Manu; Cerbule, Kristine; Nielsen, Kåre Nolde; Jacques, Nadine; Lomeli, Mark Joseph Max; Tokac, Adnan; Cuende, Elsa (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-03-26)
      Several shrimp trawl fisheries use a Nordmöre sorting grid to avoid bycatch of fish. However, small fish can pass through the grid. Therefore, the retention of juvenile fish often remains an issue during shrimp trawling. We investigated the vertical distribution of deepwater shrimp (<i>Pandalus borealis</i>) and dominant bycatch species at the point where the Nordmöre grid section is installed. This ...
    • Escape of hake (Merluccius merluccius), horse mackerel (Trachurus trachurus) and blue whiting (Micromesistius poutassou) in codends with shortened lastridge ropes 

      Cuende, Elsa; Sistiaga, Manu; Herrmann, Bent; Basterretxea, Mikel; Arregi, Luis (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-09-02)
      Diamond meshes in trawl codends have limited openness, which reduces escape opportunities for roundfish. Shortening the lastridge ropes (LR) attached to codend selvedges can increase the availability of open meshes resulting in higher chances of escape. However, this availability does not imply optimal mesh openness, nor does it guarantee use. We estimate the escape probability of hake, horse mackerel ...
    • Is there a limit to the potential effects of shortening lastridge ropes on the size selectivity of diamond mesh codends? 

      Sistiaga, Manu; Herrmann, Bent; Brinkhof, Jesse; Larsen, Roger B.; Santos, Juan; Stepputtis, Daniel; Brinkhof, Ilmar; Jacques, Nadine; Cerbule, Kristine; Petetta, Andrea; Cuende, Elsa; Kvalvik, Liz Beate Kolstad (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-21)
      Shortening codend lastridge ropes can be an effective fishing gear modification to improve the size selection properties in diamond mesh codends. Lastridge ropes attached to codend selvedges withstand the longitudinal forces created by the catch building up and therefore, prevent the codend meshes from closing. However, the extent to which the lastridge ropes should be shortened to maximize the ...
    • Optimizing size selectivity and catch patterns for hake (Merluccius merluccius) and blue whiting (Micromesistius poutassou) by combining square mesh panel and codend designs 

      Cuende, Elsa; Sistiaga, Manu; Herrmann, Bent; Arregi, Luis (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-01-20)
      Gear modifications in fisheries are usually implemented to obtain catch patterns that meet management objectives. In the Basque bottom trawl fishery, gear regulations include the use of a square mesh panel (SMP) placed at the top panel of the extension piece of the trawl to supplement diamond mesh codend selectivity. However, the catch patterns obtained with this combination have raised concern ...
    • Prediction of square mesh panel and codend size selectivity of blue whiting based on fish morphology 

      Cuende, Elsa; Arregi, Luis; Herrmann, Bent; Sistiaga, Manu; Aboitiz, Xabier (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-09-24)
      Square mesh panels (SMPs) are selective devices used extensively to supplement codend size selectivity in trawl fisheries. Therefore, predictions of the effect of mesh size in both SMPs and codends on size selectivity are valuable. Here, we established a framework to predict the size selection of blue whiting through different SMPs and diamond mesh codends based on the morphological characteristics ...
    • Release efficiency and selectivity of four different square mesh panel configurations in the Basque mixed bottom trawl fishery 

      Cuende, Elsa; Arregi, Luis; Herrmann, Bent; Sistiaga, Manu Berrondo; Basterretxea, Mikel (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-01-28)
      Reduction of discards from the Basque mixed bottom trawl fishery is a challenge. To improve the selective properties of the gear used by the fleet and supplement codend size selection, a square mesh panel (SMP) installed in the upper panel of the trawl was introduced in 2006. However, recent studies have shown that the release efficiency of this SMP is low due to lack of contact between the fish and ...
    • Stimulating release of undersized fish through a square mesh panel in the Basque otter trawl fishery 

      Cuende, Elsa; Arregi, Luis; Herrmann, Bent; Sistiaga, Manu Berrondo; Onandia, Inigo (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-11-19)
      Discards of regulated species in the Basque mixed trawl fishery are a challenge. In 2006, a square mesh panel (SMP) was introduced in the fishery to increase the release efficiency of undersized fish. However, studies have shown that the selectivity in this fishery is based on codend selectivity and the release through the SMP is inefficient due to low contact between fish and the SMP. In order to ...