Identification of phytoplankton species in the coastal waters of Moorea will assist in determining potential red tide producers. Several species of micro algae, phytoplankton, produce toxins known as harmful algal blooms (HAB), more commonly known as red tides. Worldwide, HABs are on the rise due to increased ocean water temperatures. Toxin production by HABs can have dramatic health and economic impacts on ocean environments resulting in the illness or death of fish, marine mammals, sea birds and more rarely humans. HABs cause shellfish poisonings that can cause human illness (e.g. vomiting, neurological problems, mortality). Additionally, HABs lead to substantial financial loss to industries (e.g. oyster, fishing). Human health (e.g. respiratory problems, skin irritations, ear infections) can also be impacted by red tides.