By Sherry Martin / Cornell Cooperative Extension
Despite years of care, Skaneateles Lake faces an ongoing threat of invasive species such as hydrilla and Asian clam. These species can invade waterfront paths and litter beaches with sharp shells and weed mats. In addition, they clog intake pipes; cycle nutrients in the water column, which promotes algal blooms, and decrease oxygen for desired native species. Invasive species in a lake can decrease property values, shrink local tax revenue, reduce fish populations and lower the tourism dollars that are vital to the region’s economy, in addition to the millions of dollars spent on control and management.
First detected in the Cayuga Inlet in August 2011, hydrilla quickly became a regional priority before the plant could advance across the Finger Lakes.
Hydrilla verticillata stems can grow 6 to 8 inches per day and extend 25 feet in length; these plants can blanket lakes with tangling mats of vegetation. The plant’s tubers and turions are broken by boats and paddles, allowing the plant to reproduce from the fragments. Wet boats create suitable habitat for fragments to live for weeks before invading another water body.
This year, both endothall and fluridone herbicide applications have been applied to 100 and 166 acres of Cayuga Lake Inlet, respectively, to control growth of the plant. Plant monitoring within the inlet is conducted by trained volunteers and aquatic plant specialists. Hydrilla has not been found growing in Cayuga Lake since treatment. Tubers can remain dormant in the sediment for several years; therefore, applications of herbicide will likely be necessary for the next eight years to kill all plant remnants.
Asian clam reproduces quickly and covers sandy and gravel lake bottoms. In Lake George, the Asian clam was discovered in August 2010. Soon after, the Lake George Asian Clam Rapid Response Task Force was created to take action. According to the task force, efforts in 2011 alone cost more than $630,000. In Owasco Lake, preliminary data from the Darrin Fresh Water Institute suggests the infested lake area occupied by Asian clams totals about 160 acres, but overall abundance is lower than in 2011.
The Asian clam was recently discovered in Otisco Lake to the east, and now poses a more imminent threat to Skaneateles Lake.
With invasive species, most regions don’t have resources established to take action until the threat covers entire regions and cheaper control methods are no longer an option. Some have established laws to curtail the spread of invasive species. In Tompkins County, it is unlawful to transport whole or parts of aquatic plants and animals, with penalties similar to a traffic ticket, costing the offender $250. Prevention and early detection of aquatic hitchhikers is the key to maintain the ecological health of Skaneateles Lake and prevent high costs of controlling future infestations.
Join Cornell Cooperative Extension for an Asian clam and hydrilla identification, prevention and monitoring workshop 6 to 7:30 p.m. Wednesday at Skaneateles YMCA, 97 State St. We have live Asian clams available for identification.
For more information and to register, call 315-424-9485, ext. 232. Details are available at http://watershed.extendonondaga.org/; please visit this link to sign up for our Wave Review e-newsletter.
Sherry Martin is water quality community educator for Cornell Cooperative Extension of Onondaga County