Estimating copepod and naupliar production rates in the Bohol Sea using a rotisserie-inspired plankton wheel

Abstract

Copepod egg and naupliar production rates in the vicinity of an upwelling area (Dipolog Bay site, northern Zamboanga) and an estuarine plume area (Butuan Bay site) in the Bohol Sea were determined onboard the research vessel M/V DA-BFAR during an oceanographic cruise conducted on 21–26 February 2013. A relatively inexpensive rotisserie-inspired plankton incubator and its operation are described. This plankton wheel design has four compartments, each holding 20 1-L bottles, providing sufficient replication of the experiment. It is powered by 220 V AC supplied on board, but is also equipped with a lever for manual operation in case of power interruptions. Community egg and naupliar production was generally higher in the upwelling site than in the estuarine plume site. Species-specific egg production rates for Oncaea clevei (19.05 eggs female^–1 day^–1, throughout), Microsetella norvegica (28.57), Macrosetella sp. (16.67), Parvocalanus sp. (11.90), Rhincalanus nasutus (33.33), and Oithona plumifera (11.90) were recorded in the upwelling site. Egg production rate values in the estuarine plume site were 9.52, 9.52, and 7.14 for Parvocalanus sp., O. plumifera, and Acrocalanus gibber, respectively. These results are comparable with those reported in other studies, supporting the utility and reliability of the plankton wheel system for use in experiments conducted onboard sea-going vessels.