SS4.04 The Relevance of Gelatinous Zooplankton to Interdisciplinary Linkages
Date: Friday, June 14, 2002
Time: 11:00:00 AM
Location: Saanich
 
PittKA, The University of Sydney, Sydney, Australia, kpitt@bio.usyd.edu.au
Kingsford, M, J, James Cook University, Townsville, Australia, michael.kingsford@jcu.edu.au
Rissik, D, , Department of Land and Water Conservation, Sydney, Australia, drissik@dlwc.nsw.gov.au
Koop, K, , Environment Protection Authority, Sydney, Australia, koopk@epa.nsw.gov.au
 
EFFECTS OF JELLYFISH BLOOMS ON THE TROPHIC AND NUTRIENT DYNAMICS OF A COASTAL LAGOON
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Replicate experiments, using mesocosms, were conducted during May and September 2001 to examine the effects of the zooxanthellate jellyfish, Catostylus mosaicus (Scyphozoa, Rhizostomeae), on the trophic and nutrient dynamics of a coastal lagoon in New South Wales, Australia. After five days, concentrations of NH3, NOX and PO4 were similar between mesocosms with and without jellyfish indicating that jellyfish did not actively take up inorganic nutrients from the water column. Mesocosms containing jellyfish had greater concentrations of chlorophyll and much smaller concentrations of zooplankton than mesocosms without jellyfish. Results were similar for both experiments. We conclude that predation by jellyfish on zooplankton reduces grazing pressure by zooplankton on phytoplankton. Population blooms of jellyfish could indirectly exacerbate or possibly cause phytoplankton blooms.