Lag effect of climate change on CPUE of Thunnus albacares and Katsuwonus pelamis in the western and central Pacific Ocean purse seine fishery:An LSTM-Based study
Yellowfin tuna(Thunnus albacares)and skipjack tuna(Katsuwonus pelamis)are pelagic and highly mi-gratory species,serving as primary targets in global pelagic fisheries.Their population distribution and abundance are susceptible to the impacts of climate-induced changes in the marine environment,exhibiting a response lag.In order to explore the influence of climate change on the juvenile populations of yellowfin tuna and skipjack tuna in the western and central Pacific Ocean(WCPO)and the associated lag effects,this study,based on Long Short-Term Memory(LSTM)neural networks,analyzed the impact of the Oceanic Niño index(ONI)on the Catch per Unit Ef-fort(CPUE)of yellowfin tuna and skipjack tuna in the WCPO purse seine fishery from 1982 to 2021.Different time step lengths were employed to simulate the lag effects(0-12 months)of CPUE response to ONI.The results indic-ate LSTM is a suitable tool for analyzing the lag effects of relationship between the abundance of pelagic species,such as yellowfin tuna and skipjack tuna,and environmental factors like ONI.In the WCPO regions north and south of the equator,there exists a time lag in the response of juvenile yellowfin tuna and skipjack tuna CPUE to ONI,with the optimal lag period being 12 months for each region.The correspondence of the optimal lag period with the age of the harvested population(nearly 1 year)suggests that the reproductive capacity or survival rate of juvenile yellowfin tuna and skipjack tuna is influenced by climate change and the resulting changes in the marine environ-ment.The research methodology and results provide new insights for subsequent studies in analyzing the stock dy-namics and distribution of key species in the WCPO.
Thunnus albacaresKatsuwonus pelamisOceanic Niño indexlag effectLSTMwestern and central Pacific Ocean
万方数据
维普
