Marine Biology

, Volume 86, Issue 1, pp 47–54 | Cite as

Clearance rates of the salp Thalia democratica fed naturally occurring particles

  • D. Deibel


Net-captured aggregate stages of the salp Thalia democratica were fed naturally occurring particles in 2-liter bottles onboard ship. The goal was to compare clearance rates of net-captured T. democratica fed natural particles to clearance rates previously determined in laboratoryborn T. democratica fed monocultures of phytoplankton. On a cruise from 19–29 April, 1979, clearance rates were estimated by monitoring the decrease in concentration of particles with a multi-channel Coulter Counter TA II over a particle size range of 2 to 32 μm equivalent spherical diameter (E.S.D.). Clearance rates were slightly lower than those measured in the laboratory, decreasing 3-fold over an 18-fold increase in the initial food concentration. Ingestion rates were slightly higher than those measured in the laboratory, increasing about 6-fold over the same range of food concentration. Within the particle concentration range examined (0.08 to 1.34 mm3l-1), there was no lower threshold of food concentration below which clearance of particles ceased. There was no effect of the concentration of T. democratica on clearance rate over a range of 2.5 to 11.5 salps l-1. The mean hourly ration was 2.0% of body carbon.


Phytoplankton Size Range Food Concentration Ingestion Rate Lower Threshold 
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Copyright information

© Springer-Verlag 1985

Authors and Affiliations

  • D. Deibel
    • 1
  1. 1.Skidaway Institute of OceanographySavannahUSA

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