The Cayuga Lake HABs Monitoring Program

The Cayuga Lake HABs Monitoring Program

Every week, HABs Harrier volunteers patrol designated stretches of the Cayuga Lake shoreline and report whether or not a harmful algal bloom is observed. If a suspicious HAB is observed, the trained volunteer will rush a water sample to the Community Science Institute (CSI) lab in Ithaca. At the lab, CSI analysts perform a microscopic analysis to determine the cyanobacteria taxa present, the concentration of total chlorophyll a as a measure of bloom biomass, and the concentration of microcystin toxin.

 The Cayuga Lake HABs Monitoring Program is unique in that it is the only volunteer HABs monitoring program in the state that includes a lab certified to conduct the microcystin toxin analysis. Having a local certified water testing lab allows the program to quickly report the results of bloom sample analysis. After a suspicious bloom has been reported, and a sample has been sent to the lab, results of sample analysis are posted on CSI’s online HABs Reporting Page within 24-72 hours at

The goals of the monitoring program can be summarized as follows:

  1. To quickly provide information and alter the public of cyanobacteria bloom occurrences on Cayuga Lake in order to help manage the risks that these blooms may present.
  2. To develop information on HABs occurrences in order to better the understanding of HABs and the factors which may promote their development on Cayuga Lake.

Below is a flow chart demonstrating the two routes in which suspicious HABs may be reported, either by trained volunteers or to the public, to the Cayuga Lake HABs Monitoring program. 

The 2020 HABs Monitoring Program

HABs Harrier Quadrant Leaders – 

Northwest Quadrant Leader

Bill Ebert

Northeast Quadrant Leader

Christy VanArnum

Southwest Quadrant Leader

John Abel

Southeast Quadrant Leader

Glenn Ratajczak 

The 2019 HABs Monitoring Program 

Results –

The 2019 HABs Monitoring Program grew to have over 80 volunteers monitoring nearly 50% of the Cayuga Lake shoreline. A total of 67 suspicious blooms were sampled and confirmed to be cyanobacteria blooms by CSI, marking an increase of 27 HABs over 2018. Moreover, 60% of the blooms occurred in early July, mainly in the southern half of the lake. Only one of the July bloom occurrences had microcystin concentrations above the guidance value for waters used for recreation of 4µg/L. From late August into early October, 25 blooms occurred along the northern-most 8 miles of shoreline, with an average microcystin toxin concentration of 347.73µg/L. CSI will continue to monitor for seasonal patterns and other HAB trend occurrences in the coming 2020 HABs Monitoring Program. Thank you to all of the HABs monitoring volunteers!

HABs Harrier Quadrant Leaders –

Welcome Southeast Quadrant Leader Glenn Ratajczak!


“What Cayuga Lake means to me goes beyond the recreational use and tourism it attracts. It is a lifeline to the community by acting as an almost unlimited source of fresh drinking water, which is becoming more rare around the world due to changing weather patterns. Therefore it is very important that we protect it from natural or anthropogenic sources of contamination.”

As Production Manager at Bolton Point Water System, Glenn was already monitoring the shoreline near their intake. So, when he heard about our HABs monitoring program, he said he knew he needed to be a part of this important project!

Glenn has also been a longtime advocate for citizen science. He was one of the founding board members of the Clean Air Coalition of Western New York, which battled a processing plant that was emitting benzene into a nearby neighborhood. He has also worked on bringing participatory budgeting to the City of Buffalo, where community members would have a say in where discretionary funding is spent. 

When asked what Cayuga Lake meant to him, Glenn responded, “What Cayuga Lake means to me goes beyond the recreational use and tourism it attracts. It is a lifeline to the community by acting as an almost unlimited source of fresh drinking water, which is becoming more rare around the world due to changing weather patterns. Therefore it is very important that we protect it from natural or anthropogenic sources of contamination.”

When Glenn monitoring Cayuga Lake, he said he acts as a roadie for his daughter, who happens to be an amazing drummer!

Welcome to the team, Glenn! We are so thankful for your passion and expertise!

Welcome Southwest Quadrant Leader Andy Yale!

“I love the perspective it gives on where we are, placed among the hills.”

Andy has been enjoying Cayuga Lake since he was a boy. He likes to sail, motor, fish, and swim, but his favorite lake activity is drifting in a boat on the lake, taking in the wonderful environment. Aside from lake activities, Andy enjoys biking on the Black Diamond Trail.

Cayuga Lake was an important part of Andy’s childhood and his present; he and his family live “just above her shores.”

Welcome to the team, Andy! We are so thankful to you and your fun-loving spirit!

Welcome Northwest Quadrant Leader Bill Ebert!

Bill Ebert and his wife Jane have been living on the northwest shore of Cayuga Lake for 30 years. His relationship with the Cayuga Lake Watershed Network began five years ago when Bill and two of his granddaughters attended an evening workshop held by CLWN Stewart, Hilary Lambert, on invasive species. Bill had brought with him a bucket of unidentified slime, hoping to find someone at the workshop who knew what it was. The slime turned out to be cladophora, a non-toxic green algae commonly found in lakes. A few emails later, Bill was elected to the CLWN’s Board of Directors.

As a board member, Bill has initiated many water monitoring campaigns. Due to concern about the quality of the water coming out of Canoga Creek, Bill and the CLWN started a water quality monitoring program on Canoga and Burroughs Creeks. This program has been going strong for four years now, gathering and publicizing eye-popping data about the sources of pollution on Cayuga Lake. After the success of this program, Bill is collaborating again with the CLWN and the Finger Lakes Institute to develop a proposal for a pilot restoration project for either Canoga or Burroughs creek with the Citizen Science Institute. Additionally, Bill was enlisted along with his friend, Tom Casella, by the DEC to do the Citizens Statewide Lake Assessment Program (CSLAP), and monitor water quality at the north end of Cayuga Lake. Last summer, Bill and Tom did weekly monitoring on a stretch of lakefront to create a census of all plant species found there.

It’s easy to notice Bill’s experience in water quality monitoring and passion for Cayuga Lake. He has been an amazing asset to the CLWN organization due to his stick-to-itiveness, his ambition and his readiness to take action.

Welcome to the team, Bill! Thank you for donating your time, energy and expertise to this program!

Welcome Northeast Quadrant Leader Christy Gunderson VanArnum!

“Cayuga Lake is my entire family’s favorite place. It is critical to all who live here.”

Christy grew up and currently resides right on Cayuga Lake in Aurora. After growing up on the lake and falling in love with the water, Christy went back to college for fisheries and aquaculture and recieved a Masters Degree in Aquatic Science/Aquaculture. Christy has been working in the field of aquatic sciences for 10 years, and is now a teacher in the area. She still spends her summers on the lake.

Christy’s favorite lake activity is swimming! With a life time of experience on the lake, she was able to swim across Cayuga Lake at its widest point to Aurora several years ago.

Welcome to the team, Christy! We so appreciate your passion and support for the lake!


The 2018 HABs Monitoring Program

Results –

Monitoring HABs occurrences is essential for understanding when and where HABs occur on Cayuga Lake. In 2018, 40 cyanobacteria blooms were recorded on the lake, helping to better the understanding of HABs and the factors that promote them on Cayuga Lake. Within the data gathered, a few observations have been made.

With only 7 blooms found in 2017, it seems there was a sharp increase in the overall number of cyanobacteria blooms in that occurred on Cayuga Lake in 2018. However, it is possible that this increase may be a result of establishing the HABs monitoring program and increased surveillance of the lake. Additionally, toxins were much higher in cyanobacteria blooms that occurred in September compared to blooms that occurred in  August or July of 2018. Finally, 77% of HABs with high toxins (microcystin levels at 4 µg/L or greater) were observed in the northern half of Cayuga Lake in 2018. Detailed data from last season can be found in this spreadsheet. These are important observations that we are interested in to compare with what may be found during this upcoming monitoring season. Thank you to everyone who volunteered to monitor HABs in 2018.  We are looking forward to learning even more about HABs on Cayuga Lake at the end of the 2019 monitoring season!