The Finger Lakes’ 2024 HABs season kicked off this week with a widespread bloom reported near the northwest tip of Cayuga Lake.
Based on photos taken Monday from the dock of a homeowner on Lower Lake Road in Seneca Falls, the state Department of Environmental Conservation confirmed it as a cyanobacteria bloom, or HAB (harmful algal bloom), rather than harmless floating pollen, which is common in early June.
Although pollen was also present in the photos, the bloom was consistent with HABs in “color, texture, density and surface area covered,” said Grascen Shidemantle, executive director of the
Plus, there were dead fish in the area, indicating there were either low levels of oxygen or a toxin in the water.
In the Finger Lakes, cyanobacteria blooms produce several types of toxin, most commonly microcystin.
In recent years, all 11 Finger Lakes have been plagued by HABs. They are most frequent in September and October but can arrive earlier if lake waters are warm enough and calm.
The state’s first confirmed cyanobacteria bloom this year came May 20 in New York City’s Central Park, according to the DEC’s map of 2024 HABs locations.
So far this season, Cayuga and Honeoye (June 4) are the only Finger Lakes with reported blooms.
Exposure to HABs by touching, swallowing or breathing can cause diarrhea or nausea and skin, eye or throat irritation. It can be deadly to dogs and other pets.
Local health departments regularly close beaches when suspicious blooms are spotted.
In the early summer, patches of harmless tree pollen can be dense enough to fool the untrained eye into assuming they are HABs, which usually don’t arrive until many weeks later.
CSI, a non-profit founded in 2000, and several watershed associations in the Finger Lakes ask volunteers to take pictures of suspected blooms and submit them for analysis by the DEC. Typically, the agency will decided whether to upgrade a “suspicious” bloom to a “confirmed” bloom on the basis of the submitted photos.
CSI goes a step further. Beginning July 1, it will collect water samples from suspicious blooms to look at them under a microscope to confirm the presence of chlorophyl-a and various types of cyanobacteria.
Those tests have shown that “CSI-trained harriers (volunteers) do correctly identify HABs about 90 percent of the time,” Shidemantle said.
“To my knowledge, the Cayuga Lake HAB monitoring program is the only program in the state where bloom samples are still being collected for laboratory…
