Direct measurement of the production:biomass ratio of the subtropical calanoid copepod Acrocalanus inermis

I have measured the specific population growth rate or production:biomass(P:B) ratio of the copepod Acrocalanus inermis by an incubationtechnique. The principal advantage of this method is that itis site- and time-specific and can therefore be used to determinespatial and temporal patterns in P:B. The values for P:B determinedby this method ranged from 0.07 day^–1 to 0.36^–1,with a mean of 0.28^–1. P:B appeared constant for incubationsof up to 40 h, and did not change significantly with up to afour-fold increase in concentration of animals during incubation.Variability in P:B between two stations and among differentdates was small. ¹Present address: University of Melbourne, Department of Zoology,Parkvill, Victoria 3052, Australia