Water Temperature at Different Depths Affects the Distribution of Neon Flying Squid (Ommastrephes bartramii) in the Northwest Pacific Ocean

Abstract

Ommastrephes bartramii can vertically swim during its life, and previous studies have suggested the need to account for preferred habitat distribution influenced by water temperatures at different depths. To explore the impacts of deep-water temperature on O. bartramii spatial distribution, we constructed generalized additive models (GAMs) based on the Chinese squid-jigging fishery data and the Argo deep water temperature data during 2005–2018 in the Northwest Pacific Ocean to analyze the relationships between the local abundance of O. bartramii and deep-water temperatures. The results showed that the variables including surface water temperature (T0), water temperature at 30- and 100-m depths (T30 and T100), and water differences between T0 and T30 (D0–30) significantly affected the spatial distribution of O. bartramii. The suitable ranges of each variable are different, > 15.5°C for T0, 11–18°C for T30, < 6°C for T100, and 4–4.5°C for D0–30. The areas occupied by the suitable T30 seemed to reflect the outline of fishing ground, whereas the areas with suitable T100 were to indicate the high density of O. bartramii. The predicted suitable habitat area and high-density area for O. bartramii are also regulated by El Niño–Southern Oscillation (ENSO) events. We demonstrated how the estimates of O. bartramii spatial distribution would vary influenced by deep-water temperatures in the Northwest Pacific Ocean. This information may help develop an appropriate method for investigating the effects of deep-water temperature on species with vertical migration.