Transport of toxic dinoflagellate cysts via ships' ballast water

Abstract

Toxic dinoflagellate species that are not endemic to an area can be inadvertently introduced when their cysts are discharged with the ballast tank sediments of bulk container ships. These species, which can affect fish- and shellfish-farms, pose a serious threat to public health and aquaculture. Among 80 cargo vessels entering Australian ports, 40% contained viable dinoflagellate cysts and 6% carried the cysts of the toxic dinoflagellates Alexandrium catenella and A. tamarense (up to an estimated 300 million cysts per ship). The introduction of new Australian quarantine measures is discussed; however, the implications of this potential spreading of toxic algae are global.