Fighting against harmful cyanobacteria

The Great Pond Foundation plans to expand its operations with community partners.


Updated March 18 

The Great Pond Foundation in Edgartown and its partners have been collecting data about harmful algae blooms, of which cyanobacteria (also known as blue-green algae) was a large concern on Martha’s Vineyard in 2021, and is expected to continue so in the future. These groups now plan to expand their work during 2022, and the plans were presented to the public during a Zoom event on Tuesday afternoon. 

Great Pond Foundation biologist and executive director Emily Reddington began the event with an introduction about harmful algae blooms and cyanobacteria. She said there was no way to quantify the concentration of cyanobacteria in the Island’s ponds. Through the cooperation of the Great Pond Foundation, the boards of health, and Chilmark Pond Foundation, a “first of its kind” cyanobacteria monitoring program was developed on the Island. 

“Why we’re all here talking about cyanobacteria is because we’ve had blooms,” Reddington said, showing photos of Chilmark Pond and Squibnocket Pond contaminated with cyanobacteria blooms. “The reason we’re concerned [about cyanobacteria] is not only because it is rather colorful and alarming when you see it on the water, it can be toxic. Cyanobacteria can produce cyanotoxins, and when concentrated together, those can be dangerous to human health and other types of animal health, especially dogs who might wade in the water.” 

Cyanobacteria are small under a microscope, but on the macro level at these ponds they can get out of control and attach to one another, developing clumps. These harmful blooms are caused by heat and fertilizer, similar to terrestrial plants. Reddington acknowledged that there is not much the Island organizations can do about the environmental heat, so finding the source of the fertilizer is needed. Working with the Environmental Protection Agency and Martha’s Vineyard Commission cartographer and geographic information system coordinator Chris Seidel helped the Great Pond Foundation to find possible hot spots of nitrogen loading in the watershed. These data help put in place “remediation mechanisms” to reduce the nitrogen. 

The existence of cyanobacteria is necessary in the ecosystems they live in. Cyanobacteria are some of the earliest photosynthetic organisms, and produce a large amount of oxygen. 

“We’re not worried about them being present. We’re worried about them blooming and growing rapidly, and then developing cyanotoxins,” Reddington said. 

The role of MV Cyano, a part of the Great Pond Foundation, is to gather data and develop them into public messaging campaigns, such as maps and public service announcements. 

Great Pond Foundation scientific program director Julie Pringle presented some examples of data MV Cyano gathered. Pringle said four ponds with monitoring stations were focused on for the data collection. These were Chilmark Pond, Edgartown Great Pond, Tisbury Great Pond, and Crackatuxet Pond in Edgartown. 

“At each of these ponds, we sampled weekly except for Crackatuxet, which was biweekly,” Pringle said. “Cyanobacteria blooms and other HABs [harmful algae blooms] can be localized.” 

Each of the ponds had cyanobacteria blooms with varying levels. Squibnocket Pond had the largest spike, with nearly 800 μg/L (unit for micrograms per liter) of cyanobacteria in July. Crackatuxet had the second highest, at nearly 30 μg/L. The other ponds had cyanobacteria levels of less than 10 μg/L. To see how safe each pond is, a color system was developed: Green means no algae blooms, yellow means cyanobacteria alert, orange is a cyanobacteria bloom watch, and red means cyanobacteria bloom advisory. 

While Pringle was explaining Squibnocket Pond’s orange category risks, a man with the Zoom name “Taylor Jones” raised his virtual hand, seemingly to ask a question. The man was naked, and was promptly muted and removed from the Zoom meeting by organizers.

“So we have been Zoom bombed. How exciting,” Pringle said jokingly. “[We] apologize for that, everyone.”

The event continued without incident. 

Reddington took the stage again and explained what was in store for 2022. The Great Pond Foundation will be cooperating with the boards of health from West Tisbury, Edgartown, and Chilmark for an “Ecosystem Monitoring Program.” This program will help the foundation to better collect data and write an annual report about it. Additionally, other ponds can be tested year-round by community partners who will be taught how to test. This would all cost $2,500 per season at the start of said season, and $200 for the kit. For single samples, the kit costs $75, with a $200 deposit.

Corrected with the correct cyanobacteria color system.