Dynamic Environment & Ecosystem Health Research

Chinese mystery snails in Atlantic Canada.
A large Chinese mystery snail being held in a blue-gloved hand on a misty day



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Are Chinese mystery snails a concern for the eastern Canada region?

If you think you may have found Chinese mystery snails anywhere in Canada, please let us know! Take a photograph & make a note of the location (lake name) and details, then send us an email at mystery.snail.reports@gmail.com. If you like, you can report it via the iNaturalist app, then give us a heads-up via the email above.

Many lakes and rivers in Nova Scotia, New Brunswick, Prince Edward Island and Newfoundland have been found to have Chinese mystery snails.  To date, most work on aquatic invasive species only focused on sport fish species. However invasive aquatic invertebrates such as the Chinese mystery snails are also of concern. The Chinese mystery snails are an aquarium & food species native to east Asia which may be spreading through the Shubenacadie waterway system in Nova Scotia and the Saint John System in New Brunswick. Reports also have been made from Newfoundland and Prince Edward Island.

Chinese mystery snails, Cipangopaludina chinesis (synonyms: Bellamya chinensis, Paludina chinensis), are more recently discovered in Nova Scotia lakes and New Brunswick river systems at high numbers. Those are  thought to be probable aquarium species released inappropriately into lakes. Those snails have been reported widely across the USA but are not as well studied in Canada.  

A hand holding a number of large Chinese mystery snails recently collected from a lake. In the backgroud is a white cooler full of water and snails with a yellow collecting bucket.

This snail species orginates from the far east of Asia & Russia regions. Chinese mystery snails are a very hardy species which can tolerate a wide range of temperatures in freshwater ecosystems. Those snails have a "trapdoor" (operculum) covering their shell opening providing significant protection.

Chinese mystery snails have gills for underwater respiration and can survive extended periods in air. In addition, those snails are live-bearing (does not lay eggs), with female snails having the capacity to contain over 100 fertilized embryos for eventual development and release as juvenile snails.

There is concern that the Chinese mystery snails may be distrupting native mussel and snail populations, impacting fish feeding patterns and even shifting nutrient cycling in lakes which could encourage algal blooms.

We are collaborating with Department of Fisheries & Oceans, the New Brunswick Museum, Maritime Aboriginal Aquatic Resources Secretariate (MAARS), and other groups & colleagues to map out the distribution and impact of the Chinese mystery snails.  

Underwater vehicle robot arm picking up a large Chinese mystery snail from lake sediments

Where are the Chinese mystery snails? We need your help!

If you think you may have found Chinese mystery snails anywhere in the Maritimes or/and Newfoundland & Labrador, please note the location and the date, then send us an email at mystery.snail.reports@gmail.com or leave a message with Jenny in the SMU Environmental Science office at 902-420-5737.  If you can send photos of (1) the snail(s), and (2) the habitat you found the snail in, those would be very useful.  We will follow up and once verified, add your report to our interactive map.

This will be in parallel with habitat and migration studies in selected lakes in Nova Scotia to assess the ecology and biology of the Chinese mystery snails and laboratory studies to assess the threshold tolerances of juvenile and adult snails to water chemistry ranges typical of Nova Scotia.

We are also developing a predictive model to assess where Chinese mystery snails could be found, and will be using our interactive map to assess and verify the model.

What are the impacts and ecology of the Chinese mystery snails?

Once we better understand the distribution of Chinese mystery snails, we will be able to undertake investigations of Chinese mystery snail impacts on our freshwater ecosystems.  As the Chinese mystery snails are lower-trophic species in ecosystems which have not evolved to incorporate those large snails in their food webs, we anticipate indirect and unexpected impacts. In other studies in the USA, Chinese mystery snails, in conjuction with other invasive species, have been implicated in algal blooms, reduction of native mollusk species and changing fish food web dynamics.

Two brown CMS snail shells on a pebbly substract under water, water is green with algae.

We are continuing this research in 2019-2020. If you are interested in potential applications of our research, joining our research group or would like to contribute to our data analyses, please email Dr. Linda Campbell.


DEEHR Resources
  • Sarah Kingsbury's 2019 International Conference on Aquatic Invasive Species poster (3rd place for best student poster!). Figshare link.
  • Sarah Kingsbury's 2020 Society of Canadian Limnologist meeting poster on water quality databases.  Figshare Link.
  • Draft map showing probability of Chinese mystery snail establishment across Nova Scotia using a Random Forest Model approach. Figshare link.
  • The Chinese Mystery Snail Project. Excerpted article by Sarah Kingsbury from the Mawqatmuti'kw magazine (Winter - Spring issue 10, 2019). PDF Link.
  • SMU brochure about the Chinese mystery snails in eastern Canada. PDF Link.
  • SMU ID Cards for adult Chinese mystery snails and juvenile Chinese mystery snails (PDF files)
  • Sarah Kingsbury's Chinese mystery snail MSc research website. Link.
External resources
  • Alien species in Nova Scotia. NS Government public communication document. Link.
  • Vivipare chinoise au Quebec. Link. (en francais)
  • NS Lake bythometry maps & water chemistry data. Link.
  • USGS Map of Chinese mystery snails across the USA. Link.
  • DF McAlpine et al. 2016. Occurrence of the Chinese mystery snail, Cipangopaludina chinesis (Gray, 1834) (Mollusca: Viviparidae) in the Saint John River system, New Brunswick with review of status in Atlantic Canada. BioInvasions Records 5(3):149-154. PDF Document.
  • JB Burch. 1989. North American Freshwater Snails: Introduction, Systematics, Nomenclature, Identification, Morphology, Habitats & Distribution. Walkerana 2(6):1-80. Freshwater Mollusk Biology & Conservation Link. PDF download.
  • DS Davis. 1985. Synopsis and distribution tables of land and freshwater mollusca of Nova Scotia. Nova Scotia Museum Curatorial Report No. 54. 33pp.  PDF Link.
  • KE Perez & G Sandland. Key to Wisconsin Freshwater Snails. Link. (with photos).  
  • SM Martin. 1999. Freshwater snails (Mollusca: Gastropoda) of Maine. Northeastern Naturalist 6(1):39-88. PDF Link.


Animated GIF of Meghan looking for snails in Sullivan Pond while Sarah takes notes.


Chinese mystery snails in eastern Canada.
- Reporting Chinese mystery snails.
- Readings & resources.
- Media interviews & articles.

Three snail shells of different sizes.
All images and content copyright (c) Linda Campbell and other members of Dynamic Environment & Ecosystem Health Research Group.