Scientists say the spiny water flea has the potential to disrupt the bottom of the food web in Lake Champlain and create a nuisance for recreational pursuits, such as fishing.
The tiny creature was spotted earlier this summer in the Champlain Canal, about 15 miles from the southern end of the lake.
Two juvenile fleas were identified in a water sample taken just north of Lock 9 near the Baldwin Corners Bridge in Kingsbury. Three other fleas were found near the western end of the Glens Falls Feeder Canal. However, none were detected in subsequent samples taken near Whitehall last week.
The initial samples were collected on June 12 as part of the Lake Champlain Long-term Water Quality and Biological Monitoring Project, a joint effort between the New York State Department of Environmental Conservation and the Vermont Agency of Natural Resources.
“If our data is correct, it is the first known occurrence in the Lake Champlain Basin,” said Meg Modley, aquatic nuisance species coordinator for the Lake Champlain Basin Program, which funds the program that made the discovery. “If we do absolutely nothing, they could get into Lake Champlain.”
“We are currently having a discussion about what could be done to prevent its spread. We are exploring all options of control,” she said.
Monitoring and sampling efforts have been increased to determine the scope and spread of the infestation. Scientists collected additional samples between Locks 11 and 12, and in the southernmost portion of Lake Champlain last Tuesday. Tim Mihuc, director of the Lake Champlain Institute at SUNY Plattsburgh, said they did not detect any water fleas in those samples.
“The infestation appears to be primarily in the Feeder Canal. Because it was discovered early, there is still some hope that we can prevent this from entering Lake Champlain if we take immediate action,” Mihuc said.
“We are suggesting a temporary closure of the canal above Lock 9 until a permanent solution can be developed. If we can prevent the water flow without closing the canal then that would be acceptable as well.”
He would also like to see the flow of water from the Feeder Canal diverted to the Hudson River. He said if that doesn’t happen it’s unlikely the spread can be stopped.
“Once it gets in, because it’s a small planktic organism, there is no method of control. At that point it’s too late,” Mihuc said.
On Monday, the Basin program’s Invasive Species Rapid Response Task Force released seven recommendations to control the spread the flea.
It recommended redirecting surplus water flow in the Canal to the Hudson River side of the system; determine the feasibility of developing a hydrologic barrier in the canal; increase sampling efforts to determine the extent of the problem; and a number of public outreach efforts to educate people of the problem.
Native to Eurasia, the spiny water flea was detected in the Great Lakes during the mid-1980s. Scientists believe it was carried to North America in ship ballast water.
It was first identified locally, in the Great Sacandaga Lake, in 2008. It’s believed that from there, it spread to the Stewarts Bridge Reservoir and then the Sacandaga River before reaching the Feeder Canal, which empties into the Champlain Canal.
A type of zooplankton, the spiny water flea feeds on other zooplanktons, which are tiny creatures that occupy the middle of the food web.
“In other lakes where its presence has been confirmed, a number of things happen. One, it can out-compete other zooplankton, which restructures the bottom of the food web,” said Modley.
That can be significant because a change at the bottom of the web could have repercussions up and down the food system, affecting other marine life, she said.
And because its spine is an anti-predator mechanism, many fish will not eat it, and if they do, it can cause digestive problems.
And although an individual flea can be difficult to see—fully grown they are only one half inch long—they can collect in mass and foul up fishing equipment. “They are a major nuisance to anyone who puts a fishing line in the water,” said Mihuc.
The full extent to which the creature could affect the Lake Champlain ecosystem is unknown, but Mihuc said research done on infestations on the Great Lakes suggests that it’s not likely to be positive.
Researchers are working to developing methods to prevent the spread of the spiny water flea.
Modley said there are considering several types of control, including chemical, electrical, biological and physical barriers, such as the ones suggested by Mihuc.
“As is often the case with new introductions of aquatic invasive species, there are no practical means to eradicate spiny water fleas, so limiting their spread is the only way to prevent their impacts on native aquatic communities.”
She encourages people to inspect and clean all recreational equipment—boats, trailers, fishing gear, etc.—and dry and use a disinfectant if possible. And most importantly, don’t transport water from one lake or river to another.