HARTFORD, Conn.–Connecticut has a thriving shellfish industry and has reliably produced safe clams and oysters for locals and visitors to enjoy. Although Connecticut has not experienced a harmful algal bloom (HAB)-related closure since 2003, the Department of Agriculture (DoAg)’s, Bureau of Aquaculture has consistently maintained a phytoplankton and toxin monitoring program as an early warning system, and collaborates with partner agencies to respond to potential HAB events and fish kills.
With the increasing threat of HABs globally, the reoccurrence of many harmful species along the New York border of the Long Island Sound and neighboring Rhode Island waters, along with much still to be learned about what causes and controls HABs, DoAg is continually preparing for a potential future bloom and any associated consequences for shellfish beds, growers and harvesters, and consumers.
HABs are caused by microalgae that can only be seen under a microscope; however, they can form blooms that are visible to the naked eye as discolored water. HABs are deemed harmful because they are associated with toxin production and have detrimental effects on human health and the environment. HAB species and their associated toxins can be filtered out of the water column by bivalve shellfish, like oysters and clams. Some toxins can even be lethal when concentrated in shellfish tissues.
Recent bloom events in Rhode Island and New York have prompted DoAg to expand the expertise of staff in HAB identification and management, with the goal of improving our ability to monitor for hazardous species along the Connecticut coastline to ensure the continued safety of Connecticut shellfish.
Emily Van Gulick, Fisheries Biologist I in DoAg’s Milford laboratory, attended the 2018 Monitoring and Event Response for Harmful Algal Blooms (MERHAB) training course at the Bigelow Laboratory for Ocean Sciences in East Boothbay, Maine. The intensive week-and-a-half class was led by experts with decades of experience. Fifteen participants from around the nation were selected for the training, many representing state shellfish regulatory and water quality programs.
The course instructional time consisted of lectures, hands-on microscopy identifications, and demonstrations. In addition to learning about the taxonomy (classification) and identification of more than 60 traditional and emerging HAB species in U.S. waters, the program taught about sample collection, storage, and analysis; cultivation techniques; and statistical and quantification methods.
Since returning from the training, Emily, with the assistance of DoAg’s Bureau of Aquaculture staff, has been working to advance the phytoplankton and biotoxin monitoring programs. In 2017, 116 phytoplankton samples were collected by the DoAg’s analysts and screened for HAB species.
In efforts to analyze additional samples and involve local towns, DoAg is now creating a volunteer network to collect and deliver whole water samples that will be screened for HAB species by experienced DoAg staff. This network will allow the agency to monitor additional locations along Connecticut’s coastline and help citizens and industry members better understand HABs.
–Connecticut Department of Agriculture