Cyanobacteria - Lagoon Pond

During Summer 2025 MV CYANO, a collaborative initiative among Island Boards of Health and scientists from Great Pond Foundation, identified a cyanobacteria bloom at Upper Lagoon Pond. The Oak Bluffs Board of Health issued a cyanobacteria bloom “ADVISORY” for the area directly south of the herring run and “WATCH” directly north of the herring run. See more info here.

The bloom was found on the southern portion of the Lagoon, near the herring run. See the MV Cyano site (select Lagoon Pond) for Maps.