Harmful Algal Bloom (HAB) Event Information
Bloom Code 25-3458-B4
Where
Water Body Cayuga Lake
Latitude and Longitude 42.94217, -76.73255
Segment Lakeshore Segment Northeast 1: Northern Marshes to Harris Park
County Cayuga
Extent Small Localized (few properties)
When
Bloom Reported August 22, 2025 11:00 AM
Bloom Sampled August 22, 2025 11:12 AM
Microscopic Examination August 26, 2025
What
Bloom Genera [1]
Microscopy Present Dominant
Microcystis

Bloom Chemistry
Total Chlorophyll a 704.0 ug/L
Total Microcystin and Nodularins (EPA 546) [2] 234.0 ug/L
[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 nature of the bloom seemed in flux as the sun intensified but the breeze has picked up. The currents seem to cause accumulation in different locations along the shoreline even within the fifteen minutes or so that we were on the site.

Weather
Weather
Wind speed
Wind direction
Water Temp
Air Temp