Seasons in the Bay

As the warm weather arrives at last, so do the dinoflagellates! For the first time in months, drumstick-shaped Ceratium appeared in the plankton sample collected at Pier 15. Dinoflagellates, which can swim up and down in the water column in search of nutrients, favor the warm and calm conditions common in the fall months.

This work is part of the Ocean Observatory Project, funded by the Gordon and Betty Moore Foundation.


Ceratium sp. (scanning electron micrograph) by FWC Fish and Wildlife Research Institute
Via Flickr:
Ceratium is a single-celled organism belonging to a group of algae called dinoflagellates. Ceratium is armored, meaning it has a hard outer coating. Each cell can form two to four horns that help it to float but also slow its movement in the water. This genus is both large and diverse. Ceratium can be found in cold and warm waters and from freshwater to saltwater environments worldwide. It ranges from the low tide mark to about 200 meters (656 feet) in depth. Some species are bioluminescent, meaning they light up the water with a blue glow at night. This dinoflagellate is nontoxic but may cause oxygen depletion in the surrounding waters at high cell concentrations.