Behavior of salmon toward seal-exclusion mesh
2019
Sakuragi, Y. (Hokkaido University, Hakodate, Hokkaido (Japan). Graduate School of Environmental Science) | Kobayashi, M. | Takahara, H. | Mitani, Y.
To reduce damage to fisheries caused by seals, the entrance to the holding chamber of salmon set-nets is fitted with mesh. However, the effects of the mesh on the salmon's behavior have not been examined. Here, we tested the response of salmon to meshes of different colors (white and brown) and sizes (25, 20, 18, and 16 cm) in a large experimental tank. Salmon approached brown mesh more frequently than white mesh of the same size, and avoided 16-cm mesh. Thus, brown mesh of ≧ 18 cm will maximize the entry of salmon into the holding chamber. However, we need to determine the optimum shape and maximum size of the mesh, because larger mesh will allow seals to enter more easily.
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