Harmful Algal Bloom (HAB) Event Information
Bloom Code 25-3458-B5
Where
Water Body Cayuga Lake
Latitude and Longitude 42.9255, -76.72856
Segment Lakeshore Segment Northeast 1: Northern Marshes to Harris Park
County Cayuga
Extent Large Localized
When
Bloom Reported September 01, 2025 12:05 PM
Bloom Sampled September 01, 2025 12:05 PM
Microscopic Examination
What
Bloom Genera [1]
Microscopy Present Dominant

Bloom Chemistry
[1] Genera - plural of genus, a category of classification in biology that ranks between the family level and the species level. Because there are many different species of bacteria that are difficult to distinguish, it is more useful to classify bacteria by genus rather than species.
[2] Microcystin
Map of HAB event
Bloom Description

Volunteer reports: The HAB has been brewing south of our zone at Harris Park since before 9 am and is now observed from there to our location on Water street and beyond us to the north to some extent, but not to the further north end yet. The night was completely still and the morning cool and calm. What wind does exist at the moment is still gentle (less than 5mph). It has been very sunny and the air temperature has increased from about 50F overnight to 74 now. The water has been consistently crystal clear this summer and now is covered with some streaking of the HAB in the current and more intense accumulation along the shoreline. Not much rainfall recently though we had .2 inches late last week. Before submitting the report we checked Harris park again and the marina just to the north of it (in our southern part of our zone) and the HAB had intensified in the park and was now present in the marina. It seems the bloom is growing from the south of the lake. We checked our priority site at Cayuga Marina and there was no evidence of a bloom there.

Weather
Weather Sunny
Wind speed
Wind direction
Water Temp
Air Temp