Prediction of the habitat and abundance of Dosidicus gigas off Chile under different climate scenarios

FENG Zhiping; CHEN Bingjian; YU Wei; CHEN Xinjun

doi:10.13984/j.cnki.cn37-1141.2025.01.017

Abstract：To explore the effects of climate change on the abundance and suitable habitat of Dosidicus gigas off Chile,a combination of fishery data(2011-2017)of D.gigas and environmental data(sea surface height above geoid anomaly,sea surface salinity,and water temperature at 400 m)from CMIP6 under the climate scenarios of SSP126,SSP370 and SSP585 were used to predict the spatiotemporal variations in the habitat and resource abundance from 2015 to 2100.The results showed that SSHAGA and SSS declined under ssp370 and ssp585 scenarios while remaining were relatively stable under ssp126 scenario.In contrast,Temp_400 m showed a consistent increase across all scenarios.The environmen-tal factors also displayed significant spatial differences across different climate periods.From 2015 to 2100,the habitat suitability index(HSI),percentage of suitable habitat area and resource abundance of D.gigas showed an increasing trend under SSP370 and SSP585 with a decline in percentage of unsuita-ble habitat area while changes were more stable under SSP126.In different periods of climate change,relatively higher resource abundance and suitable habitat were mainly distributed in the central and northern Chile during the three periods under SSP370 and SSP585 scenarios and in the south of 42°S un-der SSP126 scenarios.Compared with the short-term climate change,the suitable habitat and resource abundance of D.gigas within exclusive economic zone off Chile increased more than those in the high seas,and decreased less than those in the high seas in medium and long term.In addition,the center of gravity of suitable habitat for D.gigas tended to move northeastward with SSHAGA identified as the relatively key environmental factor influencing the spatial distribution.