CS39A Zooplankton - Feeding, Reproduction, Growth and Molecular Diversity
Date: Tuesday, June 11, 2002
Time: 4:45:00 PM
Location: View Royal
 
PiersonJJ, University of Washington, Oceanography, Seattle, USA, jpierson@ocean.washington.edu
Frost, B, W, University of Washington, Oceanography, Seattle, USA, frost@ocean.washington.edu
 
Fecundity and egg hatching success of Calanus pacificus and Pseudocalanus newmani during the spring bloom in Dabob Bay, WA
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The reproduction of planktonic grazers appears tightly coupled to spring diatom blooms in coastal waters. However, recent studies have questioned the strength and validity of that coupling. Whereas laboratory work has shown that high diatom concentrations can inhibit development of copepod eggs and nauplii, contradictory results have emerged from the few field studies that examined this linkage. It is imperative that we better understand the linkages between primary production and planktonic grazers in coastal ecosystems, as this is the basis for energy transfer to higher trophic level consumers, such as fish. To investigate these questions, we measured the egg production and egg hatching success of two coastal North Pacific species of copepod, Calanus pacificus and Pseudocalanus newmani in Dabob Bay (Washington State) throughout the course of the spring diatom bloom. We also collected information on the concentration of diatoms and chlorophyll, and other abundant phytoplankton taxa, in an attempt to unambiguously determine the effects of diatoms on these grazers in the sea.