Lake Elmo here in the Billings Heights has become ground zero for an invasive species never before seen in Montana. During a Montana Fish, Wildlife, and Parks hands-on training session on early detection of aquatic invasive species, class participants were surprised to find the shells of Asian clams near the boat ramp in Lake Elmo State Park. While these mollusks have been found in forty-six other states, including our neighbors South Dakota, Wyoming, and Idaho, Montana has been able to keep them out of our bodies of water until now.
Asian clams were first reported in the United States in the Columbia River in Washington in 1938. Scientists aren’t sure how they originally got to the States from Asia, but most theorize they were either brought in as food or hitched a ride on other imported shellfish. Once they entered the waterways these clams are able to drift in water currents to spread as far as possible, but it is believed that the largest reason behind their explosive growth isn’t manifest destiny, but simply tagging along in mud or water on boats and other gear.
According to the Adirondack Watershed Institute, Asian clams can be differentiated from the larger native clams already present in Lake Elmo and the rest of Montana by the distinct elevated concentric growth rings on the shell, their three cardinal teeth instead, and the fact that they are usually under 20 millimeters in size and are light tan to brown in color. CLICK HERE TO READ MORE
