Asian Clam Assessment

Surveying Lake Champlain for Asian Clams

Michael Lew-Smith with Arrowwood Environmental gives volunteers a presentation on the Asian clam, an invasive species to North America. They will set out the next day to survey for the invasive in Lake Champlain.
Image credit to the U.S. Geological Survey.
This map illustrates Asian clam distribution in the United States as of October 2012. Asian clams were first discovered in North America in 1938 in the Columbia River, Washington. Since then they have spread to 38 different states, including New York and Vermont.
Michael Lew-Smith of Arrowwood Environmental trains volunteers, including many members of the Magic Hat Brewery staff, to sieve for Asian clams. Because of their ability to spread rapidly, it is vital to regularly assess the currently unaffected water bodies for Asian clams.
Michael Lew-Smith training volunteers to sieve for Asian clams. Pictured are Magic Hat Brewery staff and Pat O'Brien.
Should a volunteer find an Asian clam in Lake Champlain during the event, it would immediately be reported to the Vermont Department of Environmental Conservation. Early detection can mean the difference between eradication and population control.
As volunteers practice sieving for Asian clams, a roll of paper towels stands ready to clean up the spills!
Michael Lew-Smith of Arrowwood Environmental demonstrates the distinguishing characteristics of an Asian clam, by showing volunteers the real thing. Not just anyone can carry Asian clams - permits are needed to transport any aquatic invasive species in Vermont.
At the Magic Hat Brewery Monica McFarland, pictured, practices using a sieve in a container of water.
Image credit to U.S. Geological Survey,
Identifying the Asian clam: Asian clams have a triangular shell, which is roughly the size of a penny (although they can grow to be 5 cm in diameter). The exterior of the shells range in color from greenish-yellow to dark brown and is marked with concentric bands that form ridges you can feel making them easy to differentiate from other mussels. The interior of the shell is a smooth white or light purple.
The day of the event was sunny and calm, with hardly a wind to ruffle the surface of the lake. Volunteers gathered on the shore of Leddy Beach to distribute supplies and prepare to search for the invasive Asian clam.
Volunteers gather their supplies for the survey: durable rubber gloves, steel sieves, buckets, warm layers, and muck boots.
Pat O'Brien pulls on waders before surveying out in the open water.
Michael Lew-Smith of Arrowwood Environmental talks to volunteers, Magic Hat Brewery staff, about Asian clam identification.
Volunteers survey the sand at Leddy Beach, searching for the invasive Asian clam.
Pools of water are left behind on the beach by this fall's low lake level. Pictured above, a volunteer kneels by the water to sift sand through his sieve.
Silhouetted against the water, volunteers wade in the shallows.
A volunteer bends to sift through the sand of the lakebed, where live Asian clams are most likely to be found.
A view of Lake Champlain from Leddy Beach on the day of the event. The sun quickly warmed the chilly morning air, and volunteers soon shed some of their layers.
Leddy Beach stretches down the coast of Lake Champlain, and will take the team of volunteers about an hour to fully assess.
Another view of Lake Champlain from Leddy Beach. A dark line of trees stands out against the blue water.
Volunteers survey the sand and pools along the shoreline of Leddy Beach. No Asian clams have been found yet.
One volunteer checks their sieve for Asian clams, while another scoops up a sieve full of sand.
Pictured above is a sieve full of shells from the beach. There are no Asian clams to be found, but some native mollusks - the fingernail clam - can look remarkably similar. Can you identify any species in this picture?
It is a bright, sunny day to be surveying on the beach.
By the end of the hour, Asian clams still hadn't been discovered on Leddy Beach. Volunteers prepare to move on to the next location - North Beach.
Volunteers walk to the end of North Beach to begin forming a search line.
View of Lake Champlain from North Beach on the day of the event. The sunlight illuminates spots of fall color in the trees, while snow coats the mountainsides in the distance.
Volunteers form a line to search North Beach for the invasive Asian clam. Some prepare to search the damp sand on the shoreline, while those with muck boots and waders stand in the shallows.
Volunteers are silhouetted by the mid-afternoon sun as they search the shallows of North Beach for Asian clams.
Halfway down North Beach, Asian clams still have not been identified. So far, so good.
Magic Hat volunteers Monica McFarland and Adam Fuller sieve for Asian clams in the shallow waters off North Beach.
At the end of a long day of surveying, volunteers gather for a group picture at Blanchard Beach. No Asian clams were discovered, but regular efforts to survey Lake Champlain are expected to continue. This event was made possible through a partnership between the Magic Hat Brewery, the Lake Champlain Committee, citizen volunteers, and Arrowwood Environmental.
Back at the Lake Champlain Committee office, staff wrapped up the day by cleaning up all the materials so they are ready to go for the next time!

Volunteers gather for a group photo

It was a sunny, crisp October morning. The rainy grey mist from the week before had cleared to reveal a stunning panorama of mountains, lake, and sand. On a beach just north of Burlington a group of volunteers, bundled in warm layers against the morning chill, were ranged in a staggered line. Those with muck boots waded through the shallow water, while the others walked along the shoreline. Every few paces each stopped to kneel and scoop up sand in a small steel sieve. They then shook away the sand, as if panning for gold, examined the contents briefly – and discarded them.

It was a search for the Asian clam, an invasive species on the verge of entering Lake Champlain. In an effort to detect invaders early, the Lake Champlain Committee teamed up with Magic Hat Brewery and Arrowwood Environmental in October 2018 to survey Burlington beaches. Using their sieves, volunteers combed the shoreline of Leddy Beach, North Beach, and Blanchard Beach for the invasive mollusk. Luckily, for this year at least, they didn’t find them.

Volunteers are vital to preventing the spread of invasive species in Lake Champlain, and LCC is grateful to everyone who came out this October!

LCC and Magic Hat will be teaming up again in the warmer months to continue the search for Asian clam. Learn more about how you can get involved in future Asian clam assessments, and other areas of invasive species management, by signing up to be an LCC volunteer! Be sure to check the box for “Aquatic Invasive Species Monitoring and Harvesting”.