Interannual and regional variations in abundance patterns and developmental timing in mesozooplankton of the western North Pacific Ocean based on Continuous Plankton Recorder during 2001-2009

• Published in: Journal of Plankton Research
• Main Authors: Yoshiki, Tomoko M., Chiba, Sanae, Sugisaki, Hiroya, Sasaoka, Kosei, Ono, Tsuneo, Batten, Sonia
• Format: Text
• Language: English
• Published: Oxford University Press 2013
• Subjects: Article; Oyashio; Pacific; Subarctic; Copepods
• Online Access: http://plankt.oxfordjournals.org/cgi/content/short/fbt047v1; https://doi.org/10.1093/plankt/fbt047

We explored interannual variations and regional differences in abundance patterns and the timing of developmental events in the dominant copepods Eucalanus bungii , Neocalanus flemingeri , Neocalanus plumchrus and Neocalanus cristatus in the western North Pacific Ocean using Continuous Plankton Recorder survey data collected in the period 2001–2009. The developmental timing of E. bungii was accelerated in the Oyashio (OY) ocean sector (40–50°N, 142–155°E) compared with that in the Western Subarctic Gyre (WSG) sector (44–59°N, 155–170°E). The Chl a concentration peaked earlier in the OY sector than in the WSG sector; consequently, we suggest that the timing of developmental events in E. bungii is driven by the timing of the phytoplankton bloom. In contrast, interannual abundance patterns and developmental timing were closely correlated in the OY and WSG sectors for three species of Neocalanus . Hence, there was spatial synchronicity in the life cycle events of Neocalanus across oceanic regions with distinct difference in phytoplankton availability and sea surface temperature anomalies. The differences between E. bungii and the three species of Neocalanus are likely attributable to differences in life cycle strategies. Therefore, species-specific responses of zooplankton to environmental variation should be taken into account when evaluating the effects of climate forcing on organisms at lower trophic levels.