Spatio-temporal distribution of habitat patterns of Scomber japonicus in East China Sea under future climatic conditions

To investigate the effects of global climate change on the habitat pattern of Scomber japonicus in the East China Sea and to slow down the adverse effects of climate change on the fishing ground of S. japonicus, based on the water temperature data of 2.5 m (Temp_2.5 m), 25 m (Temp_25 m) and 50 m (Temp_50 m) output by CMIP6 climate model, we analyzed the spatio-temporal changes of the habitat in the East China Sea under three future climatic conditions (SSP126, SSP370 and SSP585). The results show that for SSP126, Temp_2.5 m, Temp_25 m and Temp_50 m showed relatively minor changes. For SSP370 and SSP585, Temp_2.5 m, Temp_25 m and Temp_50 m showed an overall upward trend. The three factors also changed in the spatial distribution during 2015−2020, 2055−2060 and 2095−2100. The habitat suitability index (HSI) on the fishing ground and proportion of suitable habitat of S. japonicus in the East China Sea from 2015 to 2100 showed a similar downward trend under SSP126, SSP370 and SSP585 conditions. However, the proportion of unsuitable habitat area from 2015 to 2100 increased under SSP126, SSP370 and SSP585 conditions. The suitable habitats of S. japonicus were mainly distributed in the waters of 122°E−126°E and 28°N−30°N during 2015−2020, 2055−2060 and 2095−2100, while the unsuitable habitat was mainly distributed in the middle of fishing ground. In addition, the gravity center of suitable habitat of S. japonicus tended to move northward. The results suggest that the global warming is unfavorable for the formation of suitable habitat of S. japonicus in the East China Sea.