Environmental fluctuation influences the ontogenetic dispersal and distribution of two ommastrephid squids in the Pacific Ocean

Ommastrephid squids are migratory and economically important species in the Pacific Ocean. Pelagic squids have a short lifespan and are highly affected by climate change. Understanding the ontogenetic dispersal of squids under environmental fluctuations can ensure proper and scientific management of these species. Samples of neon flying squid (Ommastrephes bartramii) and jumbo flying squid (Dosidicus gigas) were collected in the Northwest Pacific and Southeast Atlantic (offshore waters of Peru) oceans, respectively, in different years. Then, five trace elements of the grounded statoliths were measured and quantified using laser ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS) to determine their ontogenetic and inter-annual variations. Furthermore, the ontogenetic dispersals of the two squid species in different years were reconstructed. The results showed that for O. bartramii, the inter-annual differences in the Sr/Ca, Ba/Ca, and Na/Ca ratios were significant (P < 0.05). However, no significant inter-annual difference was observed in the Mg/Ca ratio (P > 0.05). For D. gigas, the inter-annual differences in the Sr/Ca, Mg/Ca, and Na/Ca ratios were significant (P < 0.05). However, no significant inter-annual difference was observed in the Ba/Ca ratio (P > 0.05). Sea surface temperature (SST) indicators were selected, including the Mg/Ca ratio for O. bartramii and Sr/Ca, Ba/Ca, and Na/Ca ratios for D. gigas, and regression models were estimated. Based on a Bayesian model, the high probability of occurrence of these indicators in a particular area represented the possible optimal location of squids, and the potential ontogenetic dispersals of the two squid species in different years were reconstructed. We found that the ontogenetic dispersals of the squids differed in different years. However, they migrated in the same direction. Nevertheless, El Ni & ntilde;o-Southern Oscillation (ENSO) events affected the habitat position of squids and the size of their habitat area at each stage.

Automated summary

This study investigates the ontogenetic dispersal of squids under environmental fluctuations by measuring and analyzing the ratios of trace elements in the statoliths. The results show that the dispersal patterns of squids vary in different years but migrate in the same direction. The El Niño-Southern Oscillation (ENSO) events affect the habitat position and size of squids.