Feeding, egg production rate and hatching success of the planktonic copepod Paracalanus parvus s.l.

Abstract

An experimental study was carried out on the feeding selectivity, egg production rate (EPR) and hatching success rate of the planktonic copepod Paracalanus parvus s.l. to understand the relationship between feeding selectivity and EPR of the copepod. The female copepods of P. parvus s.l. were collected every month for the period of one year (January to December, 2012) using plankton net from Tong-yeong Marine Living Resources Research and Conservation Center, Korea. Every month, the copepods were incubated in situ with environmental parameters including temperature, salinity, and chlorophyll-a concentration. Egg production rate of the copepod ranged from 4.9-25.4 eggs female-1 day-1 (mean = 8.5 eggs) with higher values in summer than winter. Hatching success rate was high with a range of 70 to 100% throughout the year. Ingestion rates ranged from 11.5-131.2 ngChl-a female-1 day-1 (mean = 46.5 ngChl-a). The copepod ingested >20&micro m size of phytoplankton than those of either <3&micro m or 3-20&micro m. These results suggest that variation in EPR of P. parvus s.l. was closely related to temperature variation rather than that of phytoplankton.f the copepod. The female copepods of P. parvus s.l. were collected every month for the period of one year (January to December, 2012) using plankton net from Tong-yeong Marine Living Resources Research and Conservation Center, Korea. Every month, the copepods were incubated in situ with environmental parameters including temperature, salinity, and chlorophyll-a concentration. Egg production rate of the copepod ranged from 4.9-25.4 eggs female-1 day-1 (mean = 8.5 eggs) with higher values in summer than winter. Hatching success rate was high with a range of 70 to 100% throughout the year. Ingestion rates ranged from 11.5-131.2 ngChl-a female-1 day-1 (mean = 46.5 ngChl-a). The copepod ingested >20&micro m size of phytoplankton than those of either <3&micro m or 3-20&micro m. These results suggest that variation in EPR of P. parvus s.l. was closely related to temperature variation rather than that of phytoplankton.