Variation in the Catch Rate and Distribution of Swordtip Squid Uroteuthis edulis Associated with Factors of the Oceanic Environment in the Southern East China Sea

Abstract

Predictions from species distribution models are used to parameterize the environmental factors that influence the biology, distribution, and habitats of a species of interest. We fitted generalized additive models (GAMs) to spatiotemporal fishery data from torchlight fishing (2009-2013) to investigate the catch rates of swordtip squid Uroteuthis edulis in relation to changes in oceanographic conditions within the southern East China Sea, and we developed a habitat preference model. A high Jensen-Shannon divergence (JSD) value is considered to be an index of a thermal front. The results obtained using the selected GAMs revealed that the explained deviance in the catch rates pertaining to the oceanographic conditions was 45.10% throughout the year. All variables examined-sea surface temperature (SST), chlorophyll-a, sea surface height anomaly, and JSD-were statistically significant predictors (P < 0.05), and JSD explained the greatest amount of deviance (17.70%). The model predicted relatively high abundance of swordtip squid at 27-28°N in the southern East China Sea during spring and a decrease from June to August. The high Subject editor: Milo Adkison, University of Alaska-Fairbanks, Juneau

Assessing Summertime Primary Production Required in Changed Marine Environments in Upwelling Ecosystems Around the Taiwan Bank

“…Higher NPP increases zooplankton blooms, directly increasing the first-level consumer resources [70,71]. Furthermore, the downstream secondary production creates an attractive habitat for species, such as those of the Scombridae and Loliginidae families and T. albacares, which occupy high trophic levels [28,53]. Therefore, the effect of high chlorophyll-a concentrations on NPP appears to be time-lagged because of trophic transfer efficiency [32,52,72,73].…”

“…In addition to warming the SCS currents northward, these winds produce higher SST gradients in the TS [12,25]. Changes in marine environments have also been demonstrated to affect fishery resources on different spatiotemporal scales, as well as ecological factors such as ecotourism and fisheries landings [26][27][28]. The marine environmental factors not only directly affect the habitat environment of biological preference but are also impactful on the competition and predation relationship of species in the ecosystem [27].…”

Remote Sensing of Ocean Fronts in Marine Ecology and Fisheries

“…Satellite SSH data have found its applications in marine fisheries and ecology (e.g., Asch and Checkley, 2013;Liao et al, 2018;Byrne et al, 2019). The main benefit of SSH vs. SST and CHL is that SSH is an integral of vertical density structure of water column (or vertical integral) whereas SST and CHL characterize just a very thin surface layer.…”

“…et al, 2013;Chen X.J. et al, 2014;Mugo et al, 2014;Tseng et al, 2014;Liao et al, 2018;Wang Y.C. et al, 2018;Hua et al, 2020;Liu et al, 2020;Oh et al, 2020), with major target species being tuna (Mugo et al, 2014), squid (Chen X.J.…”

“…et al, 2018;Hua et al, 2020;Liu et al, 2020;Oh et al, 2020), with major target species being tuna (Mugo et al, 2014), squid (Chen X.J. et al, 2014;Mugo et al, 2014;Liao et al, 2018;Oh et al, 2020), saury (Mugo et al, 2014;Tseng et al, 2014;Hua et al, 2020), and anchovy (Liu et al, 2020).…”