The California Department of Public Health Volunteer Monitoring Program Map Viewer shows abundance of toxic phytoplankton species on a weekly interval. Visit their website to access data.
Algal blooms are composed of one or more species of phytoplankton. Some blooms are 'red tides', appearing brown to red in color, and some of these can be harmful to people or wildlife depending on the species forming the bloom. Other blooms are not visible but can still cause health problems. Learn more about algal blooms and algal bloom monitoring activities on the pages listed below.