While work continues in Lake George Village to smother Asian clams with benthic barriers, a parallel effort to survey other suitable Asian clam habitat for their presence was organized by the Lake George Asian Clam Rapid Response Task Force (LGACRRTF). Survey efforts show over 60 clean sites with no Asian clams and two small infestations in addition to Boon Bay, bringing the known number of infestations in Lake George to four. The survey is still underway.
The infestation at Boon Bay is six miles north of the Lake George Village site. It was found in mid-July by divers contracted by the Fund for Lake George who were managing Eurasian watermilfoil and also keeping an eye out for Asian clams. Survey work in the fall of 2010 after the first discovery at Lake Avenue focused on a 10- mile area of shoreline around the initial infestation, which did not go as far north as Boon Bay. In light of finding additional sites, the Task Force reconvened and decided that before moving forward with controlling the second site, more surveying was needed to determine if other populations of Asian clam exist in Lake George.
Jill Salvo from the Darrin Fresh Water Institute (DFWI) detected the third site at Norowal Marina on July 31st. In response, the LGACRRTF rallied partners and volunteers to ramp up the lake-wide survey efforts. Earlier this month, staff and volunteers from DFWI and the Lake George Association (LGA) surveyed over 60 high priority sites such as marinas, boat launches, and public beaches focusing on shallow, sandy areas – prime Asian clam habitat. A team from the LGA found a fourth infested site on August 2 that includes Treasure Cove Resort and Beckley’s Boat Launch, which are in proximity to each other.
Surveys at Treasure Cove Resort uncovered another non-native species, but one known to be in the Lake Champlain Basin and not known to cause significant harm, the Chinese mystery snail. “I had just been doing some reading on snails the week before to brush up on my knowledge for an aquatic invasive species workshop we were hosting at the LGA office,” said Emily DeBolt, the LGA’s director of education. “As soon as I saw the snails, I had a feeling that that was what they were. They are just so huge – it is really unbelievable when you see them at first.” Emily photographed the snails and sent the images to Dr. Dan Marelli, a mollusk expert, who confirmed the identification. “This is just one more example of how important it is to be out there looking, because you never know what you might find. The more we know about Lake George the better prepared we will be to protect it,” said Walt Lender, the LGA’s executive director.
Many of the high priority areas to survey for clams have been surveyed and no clams have been found; however, many more miles of shoreline remain to be surveyed. “We need additional surveying on as much of the shoreline as possible,” said Dr. Sandra Nierzwicki-Bauer, director of the Rensselaer Polytechnic Institute Darrin Fresh Water Institute. “Before we try to make any decisions about how to deal with the four sites we currently know of, we want to know if there are any other sites that need to be managed.”
The first site where Asian clams were found at Lake Avenue is nearly six acres in size and is still the largest known infested site. Based on preliminary survey work, the Boon Bay site is estimated to be nearly as large at 4-5 acres. The Norowal Marina and Treasure Cove sites are much smaller. “It remains imperative that we complete the full treatment at the Lake George Village site, the results of which will inform us as to the technical, financial, and social feasibility of controlling the clams with benthic barrier mats. The costs incurred to date at that site are roughly $400K and it will cost a few more hundred thousand to complete that treatment. Conducting the lake-wide survey is also a high priority, the results of which will help partners understand the extent of management that we may face,” said Meg Modley, Lake Champlain Basin Program.
At a meeting for elected officials held last month, reports showed over $2.5 million spent on Eurasian watermilfoil and zebra mussel management in the lake over the past decade as well as close to $170,000 on the Lake George Lake Steward Program for the past four years. Multiple groups around the lake also have strong programs to educate the public about invasive species spread prevention, but legislative help is also needed from the state. Invasive species are still being moved around by people either through recreational or commercial pursuits.
Preventing the spread of invasive species is the most cost effective solution in the long term. “Breaking the pathways of spread of highly invasive and harmful species is necessary, otherwise we are fighting a losing battle. Programs and policies are needed at multiple levels,” said Hilary Smith, director of the Adirondack Park Invasive Plant Program. “Protecting Lake George and other lands and waters from invasive species isn’t a lost cause, it can be done, but we need the state’s help with prevention to tip the balance in our favor,” she added.