Environmental drivers of unprecedented Alexandrium catenella dinoflagellate blooms off eastern Tasmania, 2012–2018
Blooms of the highly toxic dinoflagellate Alexandrium catenella (previously referred to as tamarense group 1) were first detected off eastern Tasmania in 2012 and have since been responsible for incidences of human paralytic shellfish poisoning and extended closures (up to 25 weeks) of mussel, oyster, scallop, abalone and rock lobster industries (up to 150 mg/kg PST in mussels). Investigation of meteorological and oceanographic influences indicate that the annually recurrent winter-spring blooms (June–Oct) occur within a narrow water temperature window (10–15 °C) under two distinct sets of conditions: (1) following high rainfall and land run-off, under relatively light winds; and (2) following periods of anomalously low air temperatures and associated cooling of shallow coastal waters, again under relatively light winds. The common driver of blooms appears to be the development of stratification in coastal waters, via salinity and/or temperature gradients. We propose a framework for evaluating the risk of Alexandrium with the aim of developing a forecasting capability, and compare these environmental conditions with historic data to understand the recent advent of these blooms.
Funding
Fisheries Research & Development Corporation
History
Publication title
Harmful AlgaeVolume
87Article number
101628Number
101628Pagination
1-9ISSN
1568-9883Department/School
Institute for Marine and Antarctic StudiesPublisher
Elsevier Science BvPlace of publication
NetherlandsRights statement
© 2019 Elsevier B.V. All rights reserved.Repository Status
- Restricted