Ocean warming-induced range-shifting of potential habitat for jumbo flying squid Dosidicus gigas in the Southeast Pacific Ocean off Peru

Climate-induced ocean warming may have significant influences on abundance and geographic distribution of fish species and cause range shifts and/or expansions in their habitats. The jumbo flying squid Dosidicus gigas in the Eastern Pacific Ocean is an ecologically and commercially important species. With 1-year short lifespan, D. gigas is significantly affected by climatic and environmental variability. This study used the logbook data of the 2011-2015 Chinese squid-jigging fishery off Peruvian waters, coupled with sea surface temperature (SST) data, to explore the variations in seasonal habitat suitability and habitat distribution pattern for D. gigas in the Southeast Pacific Ocean under five scenarios: SST in recent years (2011-2015) and with 0.5 °C, 1.0 °C, 2.0 °C and 4.0 °C increases in relation to the climate variability. A fishing effort-based habitat suitability index (HSI) model was developed to estimate habitat quality of D. gigas and spatial distribution of suitable and optimal habitats in relation to ocean warming. Results indicated that obvious seasonal variations were observed in the SST on the fishing ground of D. gigas with spatial variability. HSI modeling approach in this study essentially captured habitat characteristics of D. gigas from spring to winter during 2011-2015. SST increase scenarios revealed that seasonal habitat suitability of D. gigas significantly reduced, and the percentages of suitable (HSI ≥ 0.6) and optimal (HSI ≥ 0.8) habitats occupying the fishing ground dramatically decreased due to the rising SST. Moreover, an obvious southeastward movement was observed in gravity centers of D. gigas habitat under the above-mentioned five scenarios. Our findings suggested that ocean warming was likely to result in the shrinkage and southeastward range-shift in the potential high-quality habitats of D. gigas in the Southeast Pacific Ocean off Peruvian waters.