Gary Hitchcock

Our laboratory studies the environmental factors that regulate primary production and respiration in pelagic ecosystems, and more recently, the trophic transfer from primary to secondary producers. Our main regions of interest are the Florida shelf and estuaries as well as the eastern Gulf of Mexico, including the Mississippi River plume and oligotrophic Gulf waters. In the RSMAS Oceans and Human Health Center, we are supported to study the Florida ‘red tide’ organism, Karenia brevis, and concentrate on its production and respiration in natural populations and cultures, as well as the fate of brevetoxin in costal communities. A graduate student, Ms Sharein El-Tourky, is examining the secondary productivity of several copepods of Farranula spp. These copepods are key prey for the larvae of several commercially-important fish species in the Florida Current and Florida Reef Track. This research is as a cooperative effort with Prof. Sharon Smith.

Jennifer L. Jurado, Gary L. Hitchcock, and Peter B. Ortner. In press. Seasonal Variability in Nutrient and Phytoplankton Distributions on the Southwest Florida Inner Shelf. Bulletin of Marine Science.

Kelble, C.R., Ortner, P.B., Hitchcock, G.L. and Boyer, J.N. 2005. Attenuation of photosynthetically available radiation (PAR) in Florida Bay: Potential for light-limitation of primary producers. Estuaries. 28(4):560-571.

Arnold, W.S., Hitchcock, G.L., Frischer, M.E., Wanninkhof, R., and Sheng, Y.P. 2005. Dispersal of an introduced larval cohort in a coastal lagoon. Limnology and Oceanography 50(2):587-97.

Hitchcock, G.L., Lee, T.N., Ortner, P.B., Cummings, S., Kelble C. and Williams, E. 2005. Property fields in a Tortugas Eddy in the southern straits of Florida. Deep-Sea Research. 52(12): 2195-2213.

Hitchcock, G.L., R.F. Chen, G.B. Gardner, and W.J. Wiseman Jr. 2004. A Lagrangian view of fluorescent chromophoric dissolved organic matter distributions in the Mississippi River plume. Mar. Chem. 89: 225-239.

Catherine D. Clark, William T. Hiscock, Frank J. Millero, Gary Hitchcock, Larry Brand, William L. Miller, Lori Ziolkowski, Robert F. Chen and Rod G. Zika. 2004. CDOM distribution and CO2 production on the Southwest Florida Shelf. Mar. Chem. 89: 145-167.

Lane, P.V.Z., S.L. Smith, H.C. Garber, and G.L. Hitchcock. 2003. Mesoscale circulation and the surface distribution of copepods near the South Florida Keys. Bull. Mar. Sci. 72(1): 1-18.

Sharein El Tourky

One of the fundamental components of accurate oceanographic models of marine food webs is the transfer of energy through the food chain. The focus of my research is to quantify the pattern in space and time of secondary production in key genera of mesozooplankton that serve as prey for larval fish in the Florida Current. To accomplish this, I am documenting the spatial and temporal distribution of the dominant species in copepod genera from samples previously collected in NSF-sponsored field studies in the Florida Straits and Florida Reef Track. Second, I am interpreting the patterns of species distributions in the context of larval fish abundance and distribution, as previously analyzed for these samples. Third, I am testing a hypothesis that secondary production will be influenced by the spatial distribution of primary production and that, in turn, primarily reflects the upwelling of thermocline waters along the nearshore edge of the Florida Current.