Seasonal fluctuations of ichthyoplankton assemblage in the northeastern South China Sea influenced by the Kuroshio intrusion

Abstract

The distribution and assemblage of ichthyoplankton related to local hydrographic features, especially intrusion of the Kuroshio Current (KC) and Guangdong Coastal Current (GCC) in the northeastern South China Sea (NESCS) were investigated in this study. A total of 193 species of ichthyoplankton belonging to 141 genera and 66 families were recognized in summer 2015 and late‐winter 2016. The ichthyoplankton assemblage was identified with distinct seasonal differences, and the differences were responded well with the oceanography conditions. In summer, the assemblages were identified into offshore and inshore groups, as controlled by the South China Sea Warm Current (SCSWC) in off‐shelf, upwelling, and the diluted water from the Pearl River in inshore. In winter, three groups were divided, representing the southwestern inshore, intrusion of the KC in the eastern offshore, and the GCC in the northern inshore area, respectively. Furthermore, Sigmops gracilis and Vinciguerria sp.3 were probably brought into the NESCS by intrusion of the KC from the eastern Luzon Strait. In addition, high ichthyoplankton abundance was found in high chlorophyll a located in upwelling areas in the northern coastal area in summer and in the southwestern Taiwan Bank in winter, respectively. The nutrition outcropped by the upwelling together, and those brought from the Pearl River probably supported high food availability of the ichthyoplankton in the northern coast of the NESCS.

Identification of Eggs and Spawning Zones of Hairtail Fishes Trichiurus (Pisces: Trichiuridae) in Northern South China Sea, Using DNA Barcoding

“…Several studies have suggested that hydrological conditions, i.e., temperature, salinity and primary production were considered to significantly affect the occurrence and distribution patterns of ithchyoplankton (Hillgruber and Kloppmann, 1999;Franco-Gordo et al, 2002;Aceves-Medina et al, 2004;Lee and Go, 2005;de Macedo-Soares et al, 2014;Huang et al, 2017). In the present study, the eggs of Trichiurus were associated with specific water masses.…”

Species Composition and Assemblages of Ichthyoplankton in Sansha Bay, Fujian Province, China

“…For the data analysis below and specific calculation above (e.g., IRI), we combined the number of egg and larva samples together (Zhang et al, 2016;Huang et al, 2017;Hou et al, 2021a). A short hatchery period (i.e., hours to several days) and limited independent swimming capability of larvae were also the considerations for the combination of egg and larva data for analyses (Woynarovich and Horváth, 1984;Pauly and Pullin, 1988;Lechner et al, 2016;Downie et al, 2020).…”

“…The variance inflation factor (VIF) was conducted to examine the collinearity between independent environment variables. VIF < 10 indicated that the environmental variables were not collinear and were fit for CCA (Graham, 2003;Huang et al, 2017). The importance of the environmental variables was measured by interset correlation coefficients, when the value of interset correlation coefficients ≥| ±0.4| variables were regarded conservatively as biologically important (Rakocinski et al, 1996;Ramos et al, 2017).…”

Spatial distribution and seasonal variation of fish larvae in the upper 200 m of the Philippine Sea

“…Kurogi et al (2012) discerned that the Japanese conger spawns in the area along the Kyushu-Palau Ridge around 17°N, 136°E. In the western Pacific, ichthyoplankton research has focused on coastal waters due to the logistical and economic considerations of investigations (Huang et al, 2017;Zhang et al, 2019a;Zhang et al, 2020;Hou et al, 2021). Surveys carried out in the open ocean are generally focused on the Kuroshio Current region (Su et al, 2011;Sassa and Takasuka, 2019), the Oyashio Current region (Shida et al, 2007), and their transitional waters (Aoki and Miyashita, 2000;Sassa et al, 2002).…”