LAKE GEORGE - Environmental advocates are ramping up efforts to draw attention to aquatic invasive species after a water steward found zebra mussels on a boat visiting Lake Placid - and the recent discovery of Asian Clams in Lake George.
An extensive search was recently launched on Lake George following the August discovery of the tiny clam on a sandy beach near the village. While divers' surveys last week indicated the clams appeared not to be spreading past where they were first found, environmentalists said people must be vigilant to stem the incursion.
Scientists say the invasive species, also known as the "golden clam," can cause extensive ecological and economic damage.
Adirondack Park Invasive Plant Program coordinator Tyler Smith said researchers from the Darrin Fresh Water Institute of Rensselaer Polytechnic Institute found the clams on the Lake Avenue Beach during a recent research project.
"They just happened across an expanse of about 2.5 acres in total of dense beds of Asian clams," Smith said, noting the invasive species has invaded Lake Tahoe and has sparked substantial concern there among environmental experts.
Scientists note the Asian clam can self-fertilize and release up to 2,000 juvenile mollusks per day.
Smith explained the phosphorous waste excreted by the invasive species triggers large bright-green algae blooms.
"There is also the issue with the bio-fouling," he said. "They like sandy bottoms and they grow very densely. In Lake Tahoe they've seen 600 Asian clams per square meter - that's a huge number."
Experts also worry the Asian clam - like its cousin the zebra mussel - could clog up water intake pipes and other structures. Their sharp shells can also befoul swimming beaches.
It took $1.4 million to undertake clam eradication measures in Lake Tahoe. Smith noted the early discovery of clams in Lake George may be the blessing for the Lake George community, which is dependent on tourism. The lake is renowned for its clear water and ideal conditions for swimming and boating.
Smith noted crews with Aquatic Invasive Management were in Lake George removing Eurasian milfoil when the clams were discovered. Those crews switched jobs and mapped out areas infested with the Asian clam, Smith said.
"They've surveyed just about the entire lake and they've only found Asian clams in this one initial area - which is a very good thing," he said. "We feel we've managed to obtain early detection, in that the species has not reproduced and taken over the entire water body. It's impossible to remove a species once it's reached those levels."
Andrew Lewis of Aquatic Invasive Management said his crews are likely to employ an eradication method similar to that used on Eurasian milfoil. Called benthic matting, it essentially bars the mussels from acquiring nutrients and food.
"That's what is being discussed right now, although nothing is finalized," he said. "Apparently in Lake Tahoe the same method is being used to counteract the clams."
Just days after scientists began assessing the Asian clam threat in Lake George, a much more familiar invasive species reared its head in Lake Placid.
Smith said a water steward, Jeff Sann, discovered zebra mussels on a boat during a routine inspection at a boat launch on Lake Placid.
"He did the best he could to remove all of the mussels he could see," Smith said. "But he just felt he wasn't sure he got them all; it was pretty bad. In conversations with the boat owners, they said the boat had been in Saratoga Lake for 30 to 45 days. He politely asked the men to go clean their boat at a car wash, and they politely refused."
Smith added the steward had no real legal footing on which to force the boat owners to do anything. He said the village of Lake Placid has laws barring individuals from transporting invasives, as does the state.
But enforcing those laws is difficult, Smith continued.
While there's no conclusive proof Lake Placid is yet hosting any substantial number of zebra mussels, Smith said boat owners and the public need to remain vigilant to prevent the spread of invasive species in Adirondack Lakes.
Strategies to prevent the spread of nuisance species include boaters thoroughly cleaning the outside of their boats and draining all water from bait buckets and bilges before launching their boats; inspecting hulls, trailers and other equipment and removing plants, animals, mud and water; and drying one's boat and trailer in the sun for five to seven days when moving them between waterways.