2000/01/01 by Shawn K. Staton, Janice L. Metcalfe-Smith, Janice L. Metcalfe‐Smith +1 · 1 citation
Agricultural and Biological Sciences · Environmental Science · #Aquatic Invertebrate Ecology and Behavior #Biology #Bivalvia #Ecology #Fishery #Geography #Mollusca #Mollusks and Parasites Studies #Unionidae
paper · pdf · doi:10.5962/p.363954
openalex publication_date 2000/01/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
The Northern Riffleshell, Epioblasma torulosa rangiana, is a small, colourful, sexually-dimorphic freshwater mussel that lives in highly-oxygenated riffle areas of rivers and streams.Its host fish in Canada is unknown.It has suffered dramatic declines in North America over the past century, with the current distribution representing a range reduction of more than 95%.It was listed as Endangered under the U.S. Endangered Species Act in 1993.Causes of its decline include the Zebra Mussel, Dreissena polymorpha, which has infested a large portion of the subspecies' former range, and agricultural impacts.All rivers where the subspecies still occurs are located in areas of intense agriculture and forestry, which makes them susceptible to siltation and runoff of agricultural chemicals.The distribution of E. ft.rangiana in Canada is now restricted to the middle reaches of the Sydenham and Ausable rivers in southwestern Ontario.The Sydenham River population is one of only three populations in North America that still show evidence of successful reproduction, hence the preservation of this population is important for the global survival of the subspecies.It is predicted that E. t. rangiana will become globally extinct within 10 years unless measures are taken soon to protect it.