- Coastal Waters
- Rhode Island Department of Environmental Management: Interactive Map (October 2016 bloom and closure)
The RI Department of Environmental Management (RIDEM) has confirmed that twenty- six reservoir lakes, ponds, and two rivers experienced toxic cyanobacteria blooms or potentially toxic blooms between 2011 and 2016. The affected waterbodies occurred throughout the state and included nine drinking water reservoirs.
RIDEM received a one-time grant of $45,000 in federal Environmental Protection Agency (EPA) funding, which is used to support cyanobacteria monitoring activities in 2017-2018. A full estimate of the effort expended on this activity by both RIDEM and the RI Department of Health (RIDOH) is not readily available.
RIDEM and RIDOH are developing projected needs for HAB monitoring in coastal waters.
Managers struggle to maintain constant monitoring of all the bodies of water that may be at risk for a HAB event, largely due to funding constraints. In 2014, University of Rhode Island’s Watershed Watch program (URIWW) joined a new regional initiative: the New England Cyanobacteria Project which was started and is supported by EPA Region 1. The EPA provided a microscope mount for a smart phone to visualize and photograph algal species and to confirm identification, and other enhanced field monitoring supplies.
There are three projects as part of the New England Cyanobacteria Project that are using technology and public engagement to help address the problem of HABs. The first is the mobile phone app, bloomWatch, which provides an interface for people to photograph possible HABs, which will be transmitted to the appropriate authority along with details of the location and weather. The second project is Cyanoscope, which involves training citizen scientists and providing them with a digital microscope kit that interfaces with a smart phone camera. Citizen scientists can then sample water from local lakes or ponds and take microscope photos of cyanobacteria, uploading them to the website (www.inaturalist.org/projects/cyanoscope). From the website, experts can identify the species of bacteria in the water sample. Cyanoscope will eventually result in a database of where and when different species of cyanobacteria occur.
The third project is the most in depth, in which professionals and trained volunteers take detailed information on cyanobacteria concentrations. One experimental tool being used is AlgaeTorch®, which provides an instant field result for chlorophyll levels in water. This project has allowed URIWW to compare results with those of an EPA-provided lab fluorometer (the traditional way of measuring chlorophyll levels) in order to ensure the AlgaeTorch accurately measures how much cyanobacteria is present.
Together, these activities engage communities, help scientists and managers learn more about cyanobacteria in New England waters, and protect public health from the risk of HAB exposure.
Pseudo-nitzschia is a group of algae (also called phytoplankton) that is naturally occurring in Rhode Island waters. There are six species of algae in this group that may produce domoic acid, but it is difficult to tell different species apart, so high cell counts of any species in this group lead to testing for domoic acid in the water. Domoic acid can become concentrated in the bodies of filter-feeding shellfish, like clams and oysters, and when humans eat the contaminated shellfish, they suffer many serious health effects, such as nausea, vomiting, diarrhea, headaches, and amnesia.
On September 26, 2016, when routine monitoring in Narragansett Bay detected elevated cell counts of Pseudo-nitzschia, concern over human health prompted swift action. High cell counts had been found in Narragansett Bay before, but follow-up tests had never previously detected the presence of domoic acid. This time, the follow-up testing in early October did find domoic acid in the water. The RIDEM promptly closed Narragansett Bay to shellfishing. During this closure, RIDEM prioritized further investigation to find out if the shellfish held by dealers were contaminated and determine the extent of the bloom and shellfish contamination. The dealer stock was released on October 10, and the bay-wide closure was lifted on October 15, as a more aggressive temporary monitoring system was implemented. This system detected domoic acid in shellfish near Little Compton and Jamestown, leading to closure of the Sakonnet River and lower Narragansett Bay on October 20 and 21, respectively. These closures were lifted on October 29, after cell counts declined and domoic acid was no longer detected in the water or in shellfish samples. Another Pseudo-nitzschia bloom event prompted shellfishing closures in the Sakonnet River and lower bay again in March 2017.
There is no clear answer to why these blooms occurred. Near-simultaneous blooms in Maine and Massachusetts indicate that the algae may have been carried in by an ocean current. High nutrient levels caused by human activity may have also contributed to the rapid growth of Pseudo-nitzschia. Neither of these factors explain why this toxin-producing species grew and spread so fast compared to other algae. The lack of a clear cause makes it harder to predict when these events will occur, necessitating a thorough monitoring process. During recent blooms, RIDEM has done an excellent job of preventing harm to shellfish consumers, and is continuously updating its monitoring process to maintain its track record.