Summer copepod production in subtropical waters adjacent to Australia's North West Cape

• Published in: Marine biology Vol. 143; no. 5; pp. 897 - 907
• Main Authors: MCKINNON, A. D, DUGGAN, S
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01.11.2003; Berlin Springer Nature B.V
• Subjects: Ambient temperature; Animal and plant ecology; Animal, plant and microbial ecology; Biological and medical sciences; Copepoda; Crustaceans; Egg production; Fundamental and applied biological sciences. Psychology; High temperature; Marine; Marine biology; Physical growth; Plankton; Sea water ecosystems; Seasonal variations; Synecology; Indian Ocean; Australia; Oceania; ISW, Australia, Western Australia, North West Cape; Growth rate; Summer; Biomass; Spatial variation; Coastal zone; Crustacea; Marine environment; Production rate; Secondary productivity; Arthropoda; Copepoda; Invertebrata; Season; Zooplankton
• ISSN: 0025-3162; 1432-1793
• DOI: 10.1007/s00227-003-1153-1

Growth and secondary production of pelagic copepods near Australia's North West Cape (21 degrees 49 prime S, 114 degrees 14 prime E) were measured during the austral summers of 1997/1998 and 1998/1999. Plankton communities were diverse, and dominated by copepods. To estimate copepod growth rates, we incubated artificial cohorts allocated to four morphotypes, comprising naupliar and copepodite stages of small calanoid and oithonid copepods. Growth rates ranging between 0.11 and 0.83 day-1 were low, considering the high ambient temperatures (23-28 degrees C). Calanoid nauplii had a mean growth rate of 0.43 plus or minus 0.17 day-1 (SD) and calanoid copepodites of 0.38 plus or minus 0.13 day-1. Growth rates of oithonid nauplii and copepodites were marginally less (0.38 plus or minus 0.19 day-1 and 0.28 plus or minus 0.11 day-1 respectively). The observed growth rates were suggestive of severe food limitation. Although nauplii vastly outnumbered copepodite and adult copepods, copepodites comprised the most biomass. Copepodites also contributed most to secondary production, although adult egg production was sporadically important. The highest copepod production was recorded on the shelf break (60 mg C m-2 day-1). Mean secondary production over both shelf and shelf break stations was 12.6 mg C m-2 day-1. Annual copepod secondary production, assuming little seasonality, was estimated as ~ 3.4 g C m-2 year-1 (182 kJ m-2 year-1). [PUBLICATION ABSTRACT]