Standardized CPUE of Chub mackerel (Scomber japonicus) caught by the Russia’s trawls fishery up to 2023

Catch per effort is often used in fish stock assessments as an indicator related to abundance. However, CPUE can be influenced by factors other than abundance. Standardization is performed to remove their influence. CPUE Standardization was completed using generalized additive models. Four groups of variables were used: spatial (latitude, longitude), temporal (day of the year), fishery (vessel length and engine power), environmental (sea surface temperature - SST). Models based on different combination of factors were tested using information criteria (AIC, BIC). The final model includes tensor product of latitude and longitude, harmonic representation of the day of the year, vessel length, engine power and SST.