AIS Surveys on Cayuga Lake, 2025

By Catherine Farrell and Claire McMahon

This summer, the Finger Lakes PRISM Aquatic Invasive Species (AIS) Field Team, hosted by the Finger Lakes Institute at Hobart and William Smith Colleges, has been monitoring Cayuga Lake’s nearshore ecosystem. This science-driven team prioritizes early detection of aquatic invasive species (AIS) to provide rapid response to emerging invasive populations to better inform management of invasives in the lake.

On Cayuga Lake, the AIS Field Team monitors six locations near popular boat launches. These sites are areas of high concern because AIS can attach to watercraft and be transported from one waterbody to another. From June to August, the team performs monthly sampling efforts from kayaks within a half-mile radius of each boat launch. At each site, the team samples up to 300 points by tossing macrophyte sampling rakes into the water and pulling up submerged plants for identification and measurement. Both native and invasive plants are recorded, and AIS are reported to iMapInvasives, an online, GIS-based data management system.

The team also collects water quality data near each launch to gain further insights into local aquatic macrophyte ecology. These data help reveal how Cayuga Lake’s ecosystem changes over the season and from year to year, how it compares to other lakes, and can help determine which areas are most vulnerable to new invasions. Invasive species can adversely impact aquatic ecosystems, including macroinvertebrate and fish communities, so it is important to mitigate existing AIS-related issues and prevent further infestations on Cayuga Lake and other Finger Lakes. These programs are essential to Cayuga Lake to ensure it remains healthy and accessible for residents, boaters, swimmers, and nature lovers.

The Finger Lakes PRISM AIS Field Team has new staff leaders this year including a new program manager and AIS field coordinator. Catherine Farrell is the program manager and previously worked with AIS within two other NY PRISMs and recently completed her master’s degree in community ecology at Binghamton University. Claire McMahon is the new AIS field coordinator and has a background in conservation, invasive species management, and aquatic ecology. She has assisted with AIS research in other PRISMs and recently completed a master’s degree in Lake Management at SUNY Oneonta.
The AIS Field Team is excited to continue their work gathering data on aquatic invasive species throughout the Finger Lakes. Any questions, or concerns about AIS can be directed to Catherine Farrell at cfarrell@hws.edu.

Water News

2020/2022 New York State Clean Water Act Section 303(d) List of Impaired Waters

In the September 11, 2024 Environmental Notice Bulletin, the New York Department of Environmental Conservation announced that the Final 2020/2022 New York State Section 303(d) List of Impaired Waters Requiring a Total Maximum Daily Load (TMDL) and the Response to Public Comments on the Draft 2020/2022 List has been released. This Final 2020/2022 List identifies waters that do not meet applicable water quality standards and do not support applicable best uses, thereby requiring a Total Maximum Daily Load (TMDL). You can find the 2020/2022 List and the Response to Public Comments here on DEC’s website.

Pollution Prevention Plan for Cayuga Lake Watershed

The NYSDEC Interim Commissioner Sean Mahar announced that the Cayuga Lake Total Maximum Daily Load has been finalized.  A TMDL is a U.S. Environmental Protection Agency-approved nutrient pollution reduction “budget” to help restore the water quality of Cayuga Lake’s southern end for recreation and help protect drinking water. The TMDL for the lake provides a detailed analysis of phosphorus pollutant sources, recommends a 30 percent reduction of phosphorus from the watershed to meet the lake’s water quality standards, and will be used by stakeholders throughout the entire watershed to improve water quality. The TMDL for Cayuga Lake is posted under “Lake TMDLs” on the Clean Water Plans webpage along with the response to public comments (chapter 8.0) and supporting documentation (appendices).

 

Hydrilla

By Liz Kreitinger, Steward/Executive Director, Cayuga Lake Watershed Network

Managing invasive Hydrilla (Hydrilla verticillata) in Cayuga Lake requires a combination of sustained chemical treatments, public education, and cooperative efforts from lake users to prevent further spread. Since its discovery in the inlet in 2011, each Hydrilla infestation location has been targeted with herbicide treatments which have reduced plant density and slowed its spread.

However, preventing the spread of Hydrilla by local boat traffic remains a significant challenge. In June, for the first time this year, Hydrilla was detected by a Finger Lakes Partnership for Invasive Species Management (FL-PRISM) Watercraft Steward at Cayuga Lake State Park who was inspecting a motorized kayak exiting the lake. This is the furthest point north in Cayuga Lake that Hydrilla has been detected to date. Preventing Hydrilla from spreading into the shallow northern shelf of Cayuga Lake and the canal  system is a top priority due to its vigorous growth which can choke waterways for recreation and crowd out other species.  In response to the finding, the New York State Department of Environmental Conservation (DEC) and FL-PRISM have put additional effort towards surveys in areas surrounding the park. As of the beginning of August, no established fragments of Hydrilla have been found in the area.

Public awareness campaigns urging lake users to “Clean, Drain, Dry” boats and equipment, along with voluntary inspections by Watercraft Stewards, rely heavily on public cooperation, especially at private docks and informal launch sites. The Cayuga Lake Watershed Network’s education activities continue to focus on these activities and invasive species awareness.

Coordination with local partners is facilitated through the Cayuga Lake Hydrilla Task Force which now includes members from Tompkins, Cayuga and Seneca Counties. As part of an ongoing effort to manage Hydrilla in Cayuga Lake, herbicide treatments administered by the US Army Corps of Engineers (USACE) and DEC continue this summer in all three lakeshore counties. Surveys to monitor treatment effectiveness, plant community response, and possible new patches are ongoing. For details on treatment schedules and extent, water monitoring for herbicide levels, and herbicide information sheets visit our website: https://www.cayugalake.org/resources/hydrilla-information-action/.

 

Hydrilla in Cayuga Lake

The Cayuga Lake Watershed Network will be hosting the Hydrilla in Cayuga Lake 2023 Annual Updates and Panel Discussion via zoom on December 18, 2023 from 12:00-2:00 pm.  Please join us to learn and ask questions about Hydrilla and the challenges it presents to Cayuga Lake, as well as the current management strategies.  Presenters include Sam-Beck Anderson from the Finger Lakes Partnership for Regional Invasive Species Management, Richard Ruby from the United States Army Corps of Engineers and Cathy McGlynn from the New York State Department of Environmental Conservation.  To register, click here .

2023 End of year Hydrilla Public Session
2023 End of year Hydrilla Public Session Image

 

 

The Water Bulletin: The Newsletter of the Community Science Institute

The Community Science Institute (CSI) has released its Fall 2019 edition of “The Water Bulletin: The Newsletter of the Community Science Institute”  This newsletter highlights that work of CSI and the dedicated volunteers they partner with to monitor harmful algal blooms (HABs) on Cayuga Lake and the water quality of tributary streams in the Cayuga Lake Watershed.  The newsletter is available at http://www.communityscience.org/wp-content/uploads/2019/12/Water-Bulletin-Fall-2019-E-edition-1.pdf ​.

Hydrilla Hunt 2019

This is an urgent request – please reply if you can assist!

The Cayuga Lake Watershed Network needs your help checking shoreline and dock areas for hydrilla, around Cayuga Lake, from October 19 – 31.

Hydrilla Hunter

In recent weeks, hydrilla infestations have been found at new sites around the southern third of the lake, most recently at the marina in Lansing and near the mouth of Cayuga Inlet in Ithaca.

Right now is the time hydrilla makes its presence known visibly at the water surface. They need a team of people checking the shoreline, around their docks and launches, and in shallow water from October 19-31 (or later, if interested).

Could you help? It would take one to two hours of your time on one or two dates of your choice.  The Cayuga Lake Watershed Network will provide you with lake rakes and hydrilla i.d. kits and collection bags and give you simple instructions on how to report suspects to invasive plants experts.

If you are interested, please let them know – quickly! Contact Jenn at programs@cayugalake.org 

This is a serious situation – hydrilla is beginning to show up in new and unexpected places. We do not want to it to spread. Help find it early, before it takes hold and expands rapidly.

PLEASE help – just this once, or on a regular basis.

More information about hydrilla, the top aquatic invasive plant: http://www.dec.ny.gov/docs/lands_forests_pdf/hydrillafs.pdf

For more information on the Cayuga Watershed Nework:  www.cayugalake.org