Improving the predictability of harmful algal blooms around Shetland, for Scottish aquaculture
Harmful algal blooms (HABs) are often high biomass blooms, which can cause the water column to become eutrophic and undersea sediments to turn anoxic. HABs can also be of relatively low biomass, but composed of species which produce toxins. Toxins can then accumulate inside organism eaten by humans, such as mussels, scallops and oysters. When these shellfish are eaten by humans, illnesses like diarrhoea, paralysis, amnesia and death can result.
During the summer of 2013, there was an exceptionally large bloom of Dinophysis species. Although preliminary reports suggested this bloom could become harmful, shellfish in the area were still below the limit which EU regulations prohibit they be sold to consumers. A change in the prevalent wind direction on Shetland caused a large bloom of toxin forming Dinophysis spp. cells to be blown into the West coast of Shetland (Whyte et al., 2014). Some mussels were sold to prestigious restaurants in London and approximately 50 people because ill, experiencing the unpleasant symptoms of diarrhetic shellfish poisoning.
This episode demonstrates that while routine monitoring of phytoplankton and toxin concentrations within shellfish is important, sometimes HABs can grow very rapidly. It is in this context that my PhD topic will be of use.
I will be looking through past data collected by routine phytoplankton and toxin monitoring sites on Shetland to find occurrences of blooms, and data collected by continuous plankton recorder (CPR). I will attempt to link this to weather conditions around the time of the bloom. Offshore data from the CPR is important, as it will elucidate whether blooms in the ocean around Shetland are always seen around farms.
My practical work will focus on measuring the water column structure around Shetland. Some preliminary work suggests that the 100m isobath west of Shetland may be an important area where HABs can initiate. I will be using CTDs and taking water samples to allow analysis of nutrients and chlorophyll in the water at various depths.
Supervisors
Professor Keith Davidson, SAMS
Dr Callum Whyte, SAMS
Dr Andrew Dale, SAMS
Dr Beth Mouat, NAFC
Dr Andrew Turner, CEFAS
Funder
European Social Fund (ESF)
University of the Highlands and Islands
University
University of the Highlands and Islands
Publications
Paul Dees, Eileen Bresnan, Andrew C Dale, Martin Edwards, David Johns, Beth Mouat, Callum Whyte, and Keith Davidson (2017) Harmful algal blooms in the Eastern North Atlantic ocean. Proceedings of the National Academy of Sciences. www.pnas.org/cgi/doi/10.1073/pnas.1715499114
Education
2016-present: PhD student. SAMS UHI
2014-2015: MSc Applied Marine and Fisheries Ecology. University of Aberdeen
2011-2014: BSc Marine Biology. Newcastle University