Monitoring shellfish growing areas for Harmful Algal Bloom species is essential to protect the health and safety of the consumer. Tidal waters in Virginia are home to a wide variety of naturally occurring, seasonally blooming dinoflagellates that have the potential to produce compounds which are associated with many shellfish syndromes. FlowCams (Yokagawa Fluid Imaging Technologies), laboratory benchtop high-throughput water analysis instruments that capture digital images of particles, are being used to facilitate harmful algal bloom (HAB) monitoring in lower Chesapeake Bay. The associated VisualSpreadsheet software is being used to classify key phytoplankton taxa, focusing on HAB species to create image libraries. Laboratory cultures of dominant bloom species including Margalefidinium polykrikoides and Alexandrium monilatum were used to expedite library construction. Field samples were then collected and run to add images of these species from their natural habitat, particularly during blooms throughout the bloom cycle when different life stages could be observed and documented.
To date, libraries are being made for several species including M. polykrikoides, A. monilatum, Akashiwo sanguinea, Heterocapsa triquetra, Ceratium furca, Scrippsiella trochoidea, Chattonella subsalsa, H. rotundata, Prorocentrum cordatum, P. micans, Dinophysis spp. and Diplopsalis lenticula. The FlowCam is being used to monitor water quality at the oyster hatchery facilities located at the Virginia Institute of Marine Science in Gloucester Point, Virginia. Water samples are collected at several stages in the hatchery to follow water quality condition with respect to phytoplankton presence and specifically to detect HAB contaminants and the algal food sources. These data are compared with larval growth and development from spawns. Some hatcheries are also using FlowCam images to follow oyster veliger growth, health and feeding efficiency. Field collections at growing areas monitored by the Virginia Department of Health will be used to validate these libraries with the intent to use the FlowCam as a screening tool for their monitoring program.