MEPS 411:117-125 (2010) - doi:10.3354/meps08623
Enhanced pore-water nutrient fluxes by the upside-down jellyfish Cassiopea sp. in a Red Sea coral reef
Carin Jantzen1,2,5,*, Christian Wild2, Mohammed Rasheed3, Mohammed El-Zibdah3, Claudio Richter4
ABSTRACT: The common circum-tropical jellyfish Cassiopea sp., unlike other members of the Rhizostomidae (Scyphozoa), exhibits a primarily benthic life. The peculiar orientation of its exumbrella against the sediment is believed to be associated with its mainly autotrophic nutrition, i.e. exposing its zooxanthellae-bearing photosynthetic oral appendages to the sunlight. Here we show that the jellyfish also acts as a nutrient pump, drawing nutrient-rich pore waters from the permeable sediments. Depletion of pore-water ammonium in situ, light-enhanced ammonium uptake, and high rates of photosynthesis determined via oxygen flux measurements and underwater fluorometer analysis (rapid light curves) show that Cassiopea sp. effectively harnesses pore-water nutrients. At high densities Cassiopea sp. may facilitate benthic-pelagic coupling and primary production in oligotrophic coral reefs.
KEY WORDS: Cassiopea sp. · Upside-down jellyfish · Advective pore-water transport · Nutrient uptake · Nutrient regeneration · Sediment · Photosynthesis · Zooxanthellae
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Cite this article as: Jantzen C, Wild C, Rasheed M, El-Zibdah M, Richter C (2010) Enhanced pore-water nutrient fluxes by the upside-down jellyfish Cassiopea sp. in a Red Sea coral reef. Mar Ecol Prog Ser 411:117-125