Asian clam is a non-native freshwater bivalve that has been dispersed throughout North American lakes, streams and rivers. Native to Southeast Asia, it is known as one of the most widespread aquatic invasive species. It is believed to have been brought to North America as a food source and as a result was released into waterways. Asian clam is still sold commercially for bait and human consumption and in the aquarium trade.
Asian clam is native to Southeast Asia, as well as Australia, Africa, Indonesia and Turkey. It can be found in 40 states of America, including three of the Great Lakes; Erie, Michigan and Superior and the St. Clair River. Asian clam can be found in other Provinces of Canada, on Vancouver Island and the Quebec side of the St. Lawrence River.
Impacts of Asian Clam
- Rapid reproduction with densities reaching 10,000 per square meter quickly.
- Ability to self-fertilize
- Spreads rapidly by humans through fish stocking and bait
- Out-compete native species for habitat and food
- Cause millions of dollars in damage to intake pipes that are used in power and water industries
- Alter food chains and reduce biodiversity
How to Identify Asian Clam
Asian clam is similar to the native and introduced fingernail or pea clams (Pisidiids), but can be identified with these features:
- Shell is oval triangular and small; less than 25 mm, rarely exceeding 50 mm.
- Shell is light green and brown with elevated ridges.
- Serrated lateral teeth that can be seen with a hand lens.
- Muscular foot that allows for movement.
What You Can Do
- Learn how to identify Asian clam, and how to prevent the spread of this species.
- Inspect your boat, trailer and equipment after each use. Remove all plants, animals and mud before moving to a new water body.
- Don’t release any live fish into Ontario lakes or rivers.
- Drain water from live well and motor on dry land.
- Clean all recreational equipment with a high pressure wash, hot water, OR let it dry for at least 5 sunny days.
- If you find Asian Clam or other invasive species in the wild, please contact the toll-free Invading Species Hotline at 1-800-563-7711 or visit EDDMapS Ontario to report a sighting.
OFAH/ONDMNRF Invading Species Awareness Program. (2021). Asian Clam. Retrieved from: www.invadingspecies.com.
This factsheet may be reproduced for non-commercial purposes.
Header photo by Noel Burkhead
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