ITHACA, N.Y. –– The monitoring program checking Cayuga Lake for Harmful Algal Blooms (HABs) is set to this next week as the warm summer weather poses a risk for HABs growth.

HABs, which are a concentration of bacteria, grow rapidly with warm temperatures and high sunlight intensity in calm water such as Cayuga Lake.

The program, which runs through September, is a partnership with the Community Science Institute (CSI), the Cayuga Lake Watershed Network (CLWN) and Discover Cayuga Lake (DCL). Volunteers monitor the shorelines of Cayuga Lake on a weekly basis, and test potential blooms. The results of positive tests are then announced to the public.

HABs can produce dangerous toxins called cyanotoxins “that are harmful to humans, other mammals, aquatic species, and birds through ingestion, inhalation, or skin contact,” according to the CLWN. Symptoms from contact with cyanotoxins include nausea, vomiting, diarrhea, skin, eye or throat irritation, breathing difficulties, and allergic reactions.

HABs have a variety of appearances and are commonly described as looking like scattered green dots, spilled paint or linear green streaks. It can be difficult to distinguish HABs from non-toxic blooms—HABs are often mistaken for green algae, duckweed, and pollen. Therefore, it is recommended to avoid any floating scum or discolored water.

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If you observe a suspicious HAB, avoid it and report it by emailing with the location of the bloom, the date and time, and two pictures. If possible, include the GPS coordinates of its location using the Compass app or Google Maps on smartphones. Otherwise, an address or nearby landmark is sufficient. You can also call CSI at (607) 257-6606.

Before heading on the lake, you can view the interactive map regularly updated by CSI that reports all identified HABs on Cayuga Lake here.

Anna Lamb

Anna Lamb is a reporter for the Ithaca Voice. Questions? Story tips? Contact her at