AUTHOR=Kim Garam , Park Wongyu , Noh Jae Hoon , Kang Hyung–Ku 

TITLE=Seasonal and developmental variation in feeding by the copepod Calanus sinicus in the Yellow Sea

JOURNAL=Frontiers in Marine Science

VOLUME=Volume 10 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2023.1273734

DOI=10.3389/fmars.2023.1273734

ISSN=2296-7745

ABSTRACT=We investigated feeding by Calanus sinicus in the Yellow Sea over four seasons in 2019-2022 using the gut pigment method. The seasonal mean ingestion rate of C. sinicus was 16.6-42.1 for copepodite stage I (CI), 24.1-41.8 for CII, and 32.7-58.5 ng chl ind. −1 d −1 for CIII, with different seasonal fluctuations in each stage. The seasonal mean ingestion rate was 45.8-114.4     for CIV, 50.2-189.3 for CV, 96.9-438.9 for females, and 69.8-132.3 ng chl ind. −1 d −1 for males, with higher values in spring and lower values in summer. The combined grazing impacts of C. sinicus from the CI to adult stages were 1.66%, 1.43%, 2.04%, and 0.65% in spring, summer, autumn, and winter, respectively. The ingestion rate of early stages from CI to CIII was positively correlated with water temperature, whereas that of later stages from CIV to adults was positively related to chlorophyll-a concentration according to a redundancy analysis. C. sinicus actively feed on phytoplankton in spring but not in other seasons, which is likely related to changes in water temperature and non-phytoplankton prey abundance. The C. sinicus feeding on phytoplankton in the Yellow Sea was significantly greater in spring than in other seasons with high contribution of females.