Seasonal bathymetric distributions of three coastal flatfishes: Estimation from logbook data for trawl and gillnet fisheries

• Published in: Fisheries research Vol. 233; p. 105733
• Main Authors: Tomiyama, Takeshi, Yamada, Manabu, Yamanobe, Akibumi, Kurita, Yutaka
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.01.2021
• Subjects: CPUE; Flatfish; Hotspot; Inshore-offshore migration; Spawning ground; CPUE; Flatfish; Hotspot; Inshore-offshore migration; Spawning ground
• ISSN: 0165-7836; 1872-6763
• DOI: 10.1016/j.fishres.2020.105733

•Catch-per-unit-effort data of bottom trawls and gillnets for three flatfishes were analyzed.•Catchability by gillnets showed species specific seasonal patterns.•Logbook data in commercial fisheries provide useful information on the seasonal bathymetric distributions.•Information on the depths of spawning grounds was updated for each species. The present study aims to clarify the Seasonal bathymetric distributions of three coastal flatfishes (stone flounder, marbled flounder, and Japanese flounder) that are caught mainly by bottom trawls and gillnets off the coast of Fukushima, Japan, by using logbook data. All three species were found to have specific spawning depths, i.e., depths of 40–80 m, 20–40 m, and 10–60 m for stone, marbled, and Japanese flounders, respectively, with extremely high catch-per-unit-effort during their spawning seasons, reflecting spawning ground formation. Furthermore, Japanese flounder showed a tendency to expand their distribution offshore to depths deeper than 100 m after October. These results indicate interspecific variations in migration and aggregation patterns. Using logbook data and considering the seasonal catchability of each fishing gear enabled us to understand the seasonal bathymetric distribution of each species and the depths of their spawning grounds.