Harmful Algal Blooms on Cayuga Lake: Information & Updates - October 4th, 2018

Blooms reported, sampled, tested & mapped, from July 2 - Present


If you see a bloom, don’t touch it. Keep your children and dogs away.  Report the bloom to habshotline@gmail.com with the location, time, date and two photos.

What a Harmful Algal Bloom looks like (and examples of non-HABs algae): https://www.dec.ny.gov/chemical/81962.html

View the map of reported HABs locations around Cayuga Lake with test results, and the shoreline zones regularly patrolled by HABs Harriers: http://www.communityscience.org/cayuga-lake-2018-harmful-algal-blooms-results/

Learn more about HABs and Cayuga Lake: http://www.cayugalake.org/harmful-algal-blooms-habs-immediate-action-and-information.html

View a 4-minute video about the Cayuga Lake HABs monitoring program: https://www.youtube.com/watch?v=lTKrsj5PM8M&feature=youtu.be

  • Latest HABs Updates for Cayuga Lake, from CSI & DEC
  • Thank You Claire Weston & Welcome Nate Launer!

Season-closing message from Nathaniel Launer, new Community Outreach & HABs staff at the Community Science Institute

“We are reaching the end of the 2018 season, and what a summer it's been! In September alone we have collected 20 bloom samples. While it's feeling a bit more like fall outside with the crisp, cool weather and windy days, there is still a chance that a heat wave on a calm day could create conditions for more blooms to occur.

 “Most of the blooms in September were found to have high levels of the toxin microcystin. I include a condensed report of the most recent [September 13, 16 & 18] bloom results for you to review. The microcystin assays show all of these recent samples were well above the DEC "high toxin" threshold of 20ug/L. 

Sample ID

Microcystin (ug/L)

Date Sampled
















“The location of the most toxic bloom was near Seneca Falls. The weekend of September 29 - October 1st was the last scheduled weekend to monitor assigned shoreline zones. Make sure to check the map on the HABs Reporting Page for locations of the other blooms on those dates.” 

The Cayuga Lake HABs lab at CSI (the Community Science Institute) notifies lakeshore neighbors of any significant preliminary results, such as these. Once they have shared these preliminary results to the public via their reporting page and map, CSI waits for final verification of their tests from DEC. This week, DEC made public the final test results of samples submitted to them by CSI following September 4 blooms. 

As shown in this diagram, the Zone number listed in the DEC table is taken from the last two digits of the Bloom Sample Codes assigned by the 2018 Cayuga Lake HAB Monitoring Program. Bloom Sample Codes are compiled with a year number (18), the lake code (34) assigned by the DEC, a two-digit volunteer monitoring zone number, and the sequential number of the bloom in that zone.

For a complete report of up-to-date bloom sample results from the 2018 Cayuga Lake HAB Monitoring Program and the DEC, please follow the link provided below by DEC to view the HABs Reporting Map and Cayuga Lake HABs Information and Results Master Table.

Latest DEC Report

“Below are the results from [September 4] samples collected by trained volunteers on Cayuga Lake. The sampling confirmed the presence of cyanobacteria HABs in the locations listed below. The bloom status is compared to the DEC Confirmed Bloom threshold of 25 µg/L Bluegreen Chlorophyll and a Confirmed with High Toxin Bloom threshold of 20 µg/L microcystin. For a map of sampling locations see http://www.communityscience.org/cayuga-lake-2018-harmful-algal-blooms-results/




BG Chl a (µg/l)

Microcystin (µg/l)

Visual Analysis


Zone 41

Confirmed with High Toxins



Microcystis, Dolichospermum


Zone 47

Confirmed with High Toxins



Microcystis, Dolichospermum


Zone 44

Confirmed with High Toxins



Dolichospermum, Microcystis


Cayuga Lake Centroid

Confirmed with High Toxins



Microcystis, Lyngbya


Zone 16

Confirmed with High Toxins



Microcystis, Dolichospermum

“Toxin data will be forwarded upon receipt if they indicate an elevated risk. Exposure to any cyanobacteria HABs can cause health effects in people and animals when water with blooms is touched, swallowed, or when airborne droplets are inhaled. This is true regardless of toxin levels; some blue-green algae produce toxins, while others do not. Exposure to blooms and toxins can cause symptoms such as diarrhea, nausea or vomiting; skin, eye or throat irritation and allergic reactions or breathing difficulties. People and pets should avoid contact with blooms, and should rinse off with clean water if contact occurs.  For more information go to www.health.ny.gov/harmfulalgae.” 

Thank you Claire Weston & Welcome Nathaniel Launer!

During the 2018 winter and spring months, CSI Outreach Coordinator Claire Weston worked tirelessly on behalf of Cayuga Lake and all of us to establish a HABs Monitoring Program with a trained volunteer team of 70 lakewide. She has now moved to New Jersey, joining her partner there and aiming at new employment horizons. We are deeply grateful for her tireless work, tenacity and excellence. Her replacement as CSI’s Outreach and HABs Monitoring Programs Coordinator is Nathaniel Launer, contact information below. Welcome, Nate!

Watch for season-end summaries and next-steps reporting from our organizations and partners. HABs are going to be a persistent problem – let’s work together to lessen their impacts and eventually get rid of them. Thank you!

Hilary Lambert, Steward/Executive Director, Cayuga Lake Watershed Network steward@cayugalake.org  

Jenn Tufano Grillo, Staff, Cayuga Lake Watershed Network programs@ayugalake.org

Nathaniel Launer, Cayuga Lake HABs Monitoring Program Coordinator & CSI Outreach Coordinator nathaniel.launer@communityscience.org 607-257-6606


The Cayuga Lake HABs Monitoring Program is a collaborative effort led by a local consortium of three nonprofits: The Community Science Institute (CSI), the Cayuga Lake Watershed Network (CLWN), and Discover Cayuga Lake (DCL), working in collaboration with the New York State Department of Environmental Conservation (NYSDEC) and the State University of New York Environmental School of Forestry (SUNY-ESF).