Prorocentrum minimum bloom
One of the most common spring phytoplankton bloomers in the Rhode River and the Chesapeake Bay. Blooms in the Rhode are frequently caused by large freshwater intrusions flowing down the bay from the Susquehanna River in Pennsylvania. Chlorophyll values exceeding 90 micrograms per liter have been recorded during these blooms here on the Rhode. Average summer chlorophyll generally does not exceed 20 to 30 micrograms per liter. A cell count of two milliliters of fixed sample revealed over 66,000 cells per ml. Prorocentrum minimum has been associated with fish kills in other parts of the world, but to date has not been a major factor in fish kills in the Chesapeake Bay.
The spring 2001 bloom appeared heaviest on the South River which is located between the Rhode and the Severn rivers. Click here for more photos of the bloom. For a close-up photo of individual cell click P. minimum. For an updated graph in 2012 showing a huge bloom click here.
Size 15um wide, 22um long, total volume 2591.8. Temp. range1.4 to 31.43C, salinity range 0 to 16.4ppt.