Phytoplankton Observations in the Western Caribbean Sea

A study of the distribution of phytoplankton in the western Caribbean Sea shows considerable quantities of cells near the coasts of Panama and Costa Rica and over a great shoal extending far out from the Nicaraguan-Honduran coastline. At other stations in deep water far from shore, small numbers of cells occur. The high concentrations of phytoplankton are characterized by an abundance of Coccolithus huxleyi and various species of diatoms. Since the water is strongly stratified in the western Caribbean Sea, the large coastal populations are thought to have derived their nutrients from the bottom very close to shore and then to have drifted out into deeper water; likewise, the large populations over the Nicaraguan-Honduran shoal, which projects above the top of the thermocline, are considered to be influenced directly by the bottom.