Cargo vessel ballast water as a vector for the spread of toxic phytoplankton species to New Zealand

Abstract

Toxic phytoplankton can have considerable impact on human health, on commercial fisheries including aquaculture, and on the environment. There is mounting concern about these organisms, their presence or possible introduction, and their potential to cause outbreaks of poisoning. This review paper draws together records of phytoplankton blooms and toxic outbreaks in New Zealand. It also examines evidence for the hypothesis that cargo vessel ballast water is a possible vector for the spread of toxic phytoplankton species, particularly dinoflagellates, to New Zealand. Options for regulating the discharge of ballast water in order to restrict potential importations of toxic species in this way are discussed.

Keywords::

• toxic phytoplankton
• blooms
• shellfish poisoning
• dinoflagellates
• introductions
• ballast water
• shipping regulations