Potentially toxic blooms of blue-green algae have been found for the first time in Sagg Pond in Sagaponack and Old Town Pond in Southampton.
The blooms were measured by scientists from Stony Brook University in the two ponds this past week and were found to be at dangerously high levels.
Scientists have not yet determined whether the blooms are of a species that emits a neurotoxin that can be harmful to humans and pets, but the Suffolk County Department of Health issued a precautionary warning on Tuesday to residents to avoid contact with waters in the two ponds, especially those areas with discolored water or scum on the surface.
“Residents who have been recently exposed to cyanobacteria at these water bodies and have symptoms such as nausea, vomiting or diarrhea, skin, eye or throat irritation, allergic reactions or breathing difficulties are advised to seek medical attention,” the advisory said. “Though blue-green algae are naturally present in lakes and streams in low numbers, they can become abundant, forming blooms in shades of green, blue-green, yellow, brown or red. They may produce floating scums on the surface of the water or may cause the water to take on a paint-like appearance.”
Stony Brook University professor Christopher Gobler, Ph.D. noted that the presence of harmful toxins in Sagg Pond and Old Town Pond has not yet been confirmed. “We need to figure out a few more things like species of algae and toxin levels,” said Dr. Gobler, who leads the students and scientists that recorded the algae blooms. “These were picked up by my lab during our first-ever coastal pond survey, hitting all sites from Agawam through Georgica. Agawam, Georgica and Wickapogue came up high during the survey as well.”
Earlier this summer, the Stony Brook marine biologists had identified dangerously high blooms of blue-green algae in Wickapogue Pond, which is adjacent to Old Town Pond, Mill Pond in Water Mill, Lake Agawam in Southampton Village, and Georgica Pond in East Hampton. The East Hampton Town Trustees have banned the harvesting of all fish and shellfish from Georgica Pond until the blooms subside.
Some species of blue-green algae can emit a toxin called saxitoxin that can cause neurological reactions that can cause illness or even death. In 2012, a dog died after drinking water from Georgica Pond.
Dr. Gobler’s team of researchers has been enlisted to help the city of Toledo, Ohio, investigate a massive blue-green algae bloom that forced the city to shut down its municipal drinking water system earlier this summer.
Along with the soupy green blooms in freshwater ponds, the recent warm weather also spurred the expansion of blooms of a red algae species in local bays as well. Dr. Gobler said that the blooms of Cochlodinium algae, called “rust tide” by scientists for the reddish-brown hue the blooms lend to the water, now stretch across almost all of the Peconics, northeastern Shinnecock Bay and several other small embayments, including Sag Harbor Cove and Three Mile Harbor in East Hampton. The blooms even forced the Stony Brook scientists to shut down the saltwater intake at the university’s new marine research center in Southampton, which sits on a tributary of northeastern Shinnecock Bay.
Rust tide blooms have been blamed for die-offs of fish and shellfish, including the massive loss of bay scallops in Peconic and Gardiners bays in 2012.
The blooms of both blue-green algae and rust tide can be expected to persist, scientists say, until waters start to cool next month.