Growth and development of Metridia pacifica (Copepoda: Calanoida) in the northern Gulf of Alaska

• Published in: Journal of Plankton Research
• Main Authors: Liu, Hui, Hopcroft, Russell R.
• Format: Text
• Language: English
• Published: Oxford University Press 2006
• Subjects: Article; Gulf of Alaska; Pacific; Subarctic; Alaska; Copepods
• Online Access: http://plankt.oxfordjournals.org/cgi/content/short/fbl009v1; https://doi.org/10.1093/plankt/fbl009

Juvenile growth and development rates for Metridia pacifica , one of the dominant larger copepods in the subarctic Pacific, were investigated from March through October of 2001-2004 in the northern Gulf of Alaska. The relationship between prosome length (PL, µm) and dry weight (DW, µg) was determined: log 10 DW =3.29*log 10 PL -8.75. The stage durations of copepodites ranged from 3-52.5 days, but were 8-15 days under optimal condition. Seasonally, growth rates increased from March to October, and typically ranged between 0.004 and 0.285 d-1, averaging 0.114±0.007 d-1 (mean ± S.E). After standardization to 5°C (Q 10 of 2.7), growth rates averaged 0.083±0.005 d-1 and were significantly correlated to chlorophyll a , with saturated growth rates of 0.149 d-1 for C1-C3, 0.102 d-1 for C4-C5 and 0.136 d-1 for all stages combined. Measured juvenile growth rates were comparable to specific egg production rates in this species. Comparisons of our rates in this study to those predicted by global models of copepod growth rates suggested that further refinement of these models is required.