Phytoplankton, or single celled marine plants, are organisms at the base of the food chain that are the food for many higher level organisms. Of the thousands of phytoplankton species, less than hundred or so are considered harmful. Those that produce toxins (poisons) or cause physical damage with sharp spines are members of groups called diatoms, dinoflagellates and raphidophytes. In the following sections we describe which phytoplankton on west coast of North America are harmful and how they cause harm to fish, marine mammals, and sometimes even humans.
To read more about HABS and Marine Biotoxins please use the navigation bar to the right or click on the links below.