Dinophysis spp. abundance and toxicity events in South Cornwall, UK: Interannual variability and environmental drivers at three coastal sites

Dinophysis is a genus of dinoflagellates with the potential to cause diarrhoeic Shellfish Poisoning (DSP) in humans. The lipophilic toxins produced by some species of Dinophysis spp. can accumulate within shellfish flesh even at low cell abundances, and this may result in the closure of a shellfish farm if toxins exceed the recom-mended upper limit. Over the period 2014 to 2020 inclusive there were several toxic events along the South West coast of U.K. related to Dinophysis spp. The Food Standards Agency (FSA) monitoring programme measure Dinophysis cell abundances and toxin concentration within shellfish flesh around the coasts of England and Wales, but there are few schemes routinely measuring the environmental parameters that may be important drivers for these Harmful Algal Blooms (HABs). This study uses retrospective data from the FSA monitoring at three sites on the south Cornwall coast as well as environmental data from some novel platforms such as coastal WaveRider buoys to investigate potential drivers and explore whether either blooms or toxic events at these sites can be predicted from environmental data. Wind direction was found to be important in determining whether a bloom develops at these sites, and low air temperature in June was associated with low toxicity in the shellfish flesh. Using real time data from local platforms may help shellfish farmers predict future toxic events and minimise financial loss.

Automated summary

This study investigates potential drivers for Dinophysis species causing toxic events, and finds that wind direction and air temperature are associated with blooms and toxicity in shellfish flesh. The use of real-time data can help predict future toxic events and minimize financial loss.