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/.