Melo Júnior, M., L.K. Miyashita & R.M. Lopes. (2021). A 3-year study of the seasonal variability of abundance, biomass and reproductive traits of Oncaea venusta (Copepoda, Oncaeidae) in a subtropical coastal area. Journal Of Plankton Research. 43(5):751-761. Sep 2021.
A 3-year study of the seasonal variability of abundance, biomass and reproductive traits of Oncaea venusta (Copepoda, Oncaeidae) in a subtropical coastal area.
Journal Of Plankton Research
43(5):751-761. Sep 2021
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This study reports on the abundance, biomass and reproductive traits of Oncaea venusta, a common pelagic copepod in tropical oceans, in a coastal area influenced by bottom intrusions of the cold and nutrient-rich South Atlantic Central Water (SACW). In addition to O. venusta abundance and biomass, we estimated egg production and weight-specific fecundity rates by applying the egg-ratio method and incubation experiments, at monthly intervals over 3 years (July 2005-June 2008), to understand potential SACW influences on reproductive patterns. Mean abundance and biomass were low, and no differences were detected with and without SACW intrusions. Mean clutch size ([plus or minus]SD) was 65.1[plus or minus]28.9 eggs female-1 and egg production rates averaged 7.6[plus or minus]12.4 and 9.3[plus or minus]5.2 eggs female-1 day-1 (viability >80%), for the egg-ratio method and incubation experiments, respectively, corresponding to a female weight-specific fecundity from 0.03[plus or minus]0.05 to 0.04[plus or minus]0.06 day-1. Oncaea venusta abundance and biomass were positively correlated with temperature, but no SACW influence on the reproductive rates was recorded. The egg production rate and the female weight-specific fecundity were influenced by the chlorophyll a concentration and the sex ratio. Although egg production and female weight-specific fecundity rates had peak values during intrusion events, no immediate impact on population abundance was observed within the same time interval.
