Do PearlNets reduce fish CPUE? R script for data analysis ...

• Main Authors: Glemarec, Gildas, Kindt-Larsen, Lotte, Brooks, Mollie Elizabeth, Kroner, Anne-Mette
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Technical University of Denmark 2024
• Subjects: Fisheries sciences not elsewhere classified; atlantic cod
• Online Access: https://dx.doi.org/10.11583/dtu.25574055; https://data.dtu.dk/articles/software/Do_PearlNets_reduce_fish_CPUE_R_script_for_data_analysis/25574055

The mitigation trials took place onboard a Danish commercial set net vessel during three distinct periods, in November 2022, February 2023, and May-June 2023 in the Western Baltic Sea. All trials were conducted with a standard 3-folds trammel net used in this area to target Atlantic cod and flatfish. We used 18 identical net panels of approximately 60 m in horizontal length, of which 5 net panels were equipped with acrylic pearls on one of the outer net layers, resulting in 13 control and 5 treatment panels. The pearls were small acrylic glass spheres (Ø 8 mm) with a groove (4 mm long and 0.8 mm wide) into which to fit the net thread.Each fishing day during the course of the trial, the fisher set one string of nets consisting of 6 control nets, then 5 pearl nets, and lastly 7 control nets. As a result, control nets and pearl nets were always deployed on the same fishing grounds, at the same time, and soaked in the water for the same duration. The trials were recorded using electronic monitoring (EM). The EM ...