Suzuki et al. (2025)

Yasuko Suzuki (BirdLife International), Motohiro Ito (Toyo University) and his students, and Nobuhiko Sato (in an advisory role, Fisheries Research and Education Agency) continued an experimental study on a gillnet bycatch mitigation technique in collaboration with Tokyo Sea Life Park in Japan. The experiment was conducted in an aviary located at an aquarium with a dive pool containing populations of Common Murres (Uria aalge) and Tufted Puffins (Fratercula cirrhata). The goal of the study was to compare their behavior to different colors of gillnet mimic, designed so that bird safety was ensured. Preliminary results revealed subtle increase in avoidance behavior against some colors. However, it was only observed when the experiment was carried out with chumming of feed. Such avoidance behavior was not evident regardless of color when live bait fish was used, which suggests stronger stimuli is necessary to reduce gillnet bycatch at sea.

We also continued a systematic data collection project in Japan with local gillnet fishers in NW Hokkaido, including Teuri Island, a breeding site of four alcids and two cormorant species (four of them are listed in Japan’s Red Data Book). The project aimed to evaluate environmental and operational factors for seabird bycatch in gillnet fisheries. Although the number of bycaught birds reported was small during the project period, water depth where gillnets were set appeared to be an important factor. We are currently in discussion with local stakeholders to shift towards a more sustainable model for long-term systematic data collection.