Abstract
Ballast water is broadly understood today to be an important driver of marine and aquatic introductions worldwide, and it is subject to multiple national and international regulations. In the mid 1980s, marine ‘bioinvasion’ science was nascent and management nearly non-existent. A series of ballast-borne introduction crises prompted changes, including the discovery of the toxic dinoflagellate Gymnodinium catenatum , a type of plankton, in Tasmania in 1985. This article examines the socio-environmental roots of this crisis and its influence on ballast water science and policy-making. Drawing insights from critical disaster studies, it examines the transformation of the alga from an organism into a bioinvasion crisis that warranted a policy response. This translation process emerged out of decades-long socio-environmental changes on land and sea that introduced new species, catalysed a new environmental science to interpret those changes and reflected the biology and biogeography of the alga itself.