Annual variations of abundance, egg production rate, and community structure of Oithona similis in Jiaozhou Bay, the Yellow Sea

In marine ecosystems, copepods (<2 mm) play an important role in the transfer of carbon and energy to higher tropic levels. Investigations Jiaozhou Bay were carried out throughout 2017–2018, combined with laboratory experiments. The annual abundance, egg production, female prosome length, mass, clutch size, population composition, development time Oithona similis at different temperatures analyzed assess life strategies estimate generation cycles O.similis typical temperate regions mid-latitude, represented by Bay. results include: 1) abundance was characterized bimodal cycles, major peak winter (1471 ± 206 ind/m³) minor spring (740 320 ind/m³). O. not subject food limitations except January. lower mainly affected temperature (>20°C) low salinity August. Predation from large size zooplankton one factors regulating abuncance 2) Over year, production rate, mass ranged 0.03 0.02 1.21 0.25 eggs -1 d , 410 6 472 4 μm, 0.35 0.05 0.43 μg c respectively. Female both significantly negative correlated temperature( P <0.01). varied between 21 we did’t find it related other factors. 3) appeared almost all stages, reproduced continuously year. According sex ratio factors, inferred that produced four generations per year