Harmful algae and mariculture in New Zealand

Harmful algal blooms and their impacts on the Greenshell (TM) mussel indust ry in New Zealand over the last decade are reviewed. The response of the re gulatory authorities, seafood industry, and scientists to the first signifi cant toxic Gymnodinium blooms in the summer of 1992/1993 has resulted in a well-organized interest group including scientists. commercial interests, a nd public health regulators. Nearly all known toxic species occur in New Ze aland and unique and internationally accredited microalgal monitoring progr ammes have been developed. New methods, such as DNA probes. have been integ rated into the system for rapid identification of species that are difficul t to differentiate morphologically. Monitoring is carried out weekly. with results being dispatched within 24 h of sample receipt to enable risk asses sments of toxicity by shellfish harvesters. The introduction of this system has saved the shellfish industry money and has reduced the amount of conta minated product being harvested and then rejected. All the main marine biot oxins are monitored, including paralytic, neurotoxic. diarrhetic. and amnes ic shellfish toxins, and also compounds such as yessotoxin. pectenotoxin. a nd gymnodimine. Blooms that could affect farmed finfish or wild marine biot a are also reported. Harmful algal monitoring is constantly reviewed in the light of new research and incorporates local knowledge of oceanographic an d climatic conditions. (C) 2001 International Council for the Exploration o f the Sea.