Consultation on the Purple Wartyback (Cyclonaias tuberculata)
Information summary and survey for the consultations on potentially listing Purple Wartyback on the List of Wildlife Species at Risk as Threatened – Please provide input by October 31, 2022
Consultations
Let your opinion be heard!
Canada’s Species at Risk Act (SARA) provides legal protection for wildlife species at risk to conserve biological diversity. It also acknowledges that all Canadians have a role to play in the conservation of wildlife species.
Before deciding whether Purple Wartyback will be added to the List of Wildlife Species at Risk as Threatened, we would like to hear your opinion, comments, and suggestions regarding the possible ecological, cultural, and economic impacts of listing or not listing this species under SARA.
Adding a species to the List of Wildlife Species at Risk
The process of listing a species under SARA consists of several steps:
- status assessment by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC)
- public consultations to gather the opinions of Canadians
- Government of Canada decision on whether or not to add a species to the List of Wildlife Species at Risk
Facts about Purple Wartyback
The Purple Wartyback is one of Canada’s 54 freshwater mussel species and the only mussel of the genus Cyclonaias found in Canada. It is a rare mussel, only found in North America, and can reach a maximum length of 20 centimetres. It’s thick shell is typically rounded on the anterior side and squared-off on the posterior side, with shell colour ranging from yellow-green to reddish-brown. The majority of the shell is covered in prominent nodules or “bumps.”
The preferred habitat of the Purple Wartyback is medium to larger rivers in moderate to swift current with substrates of cobble, gravel, sand, and occasionally mud.
In Canada, Purple Wartyback was historically known only in the Detroit, Sydenham, and Thames rivers, and Lake Erie. It is now believed to be lost from the Detroit River and Lake Erie, though populations remain in the Ausable, Sydenham, and Thames rivers (Figure 2).
Who assigned the threatened status to Purple Wartyback?
In 2021, COSEWIC assessed Purple Wartyback as Threatened. COSEWIC is an independent committee of experts that assesses which wildlife species are in some danger of disappearing from Canada and assigns a status to these species. It conducts its assessments based on the best available information including scientific data, local ecological knowledge, and Indigenous traditional knowledge. Under SARA, a Threatened species is defined as one that is likely to become an Endangered species if nothing is done reverse the factors that are contributing to declining population trends.
Why is the Purple Wartyback at risk?
COSEWIC assessed Purple Wartyback as Threatened because of declining habitat quality. Threats to Purple Wartyback populations include pollution, climate change, invasive species (for example, Zebra and Quagga mussels, Round Goby), and dredging.
If a species is listed under the SARA
If Purple Wartyback is listed as Threatened, the prohibitions under SARA would immediately come into effect in Canadian waters. It would be illegal to kill, harm, harass, capture, take, possess, collect, buy, sell, or trade Purple Wartyback. However, activities that may affect the species or its critical habitat may be permitted under SARA section 73-74, or exempt under section 83, where that activity does not jeopardize the survival or recovery of the species.
A recovery strategy and subsequent action plan(s) would be developed to identify measures to address known threats. Critical habitat (the habitat necessary for the survival and recovery of Purple Wartyback) would need to be identified, to the extent possible, in a recovery strategy or action plan and protected from destruction. If listed, Fisheries and Oceans Canada will engage with interested parties on the development of a recovery strategy and action plan. A recovery strategy would need to be prepared within 2 years of listing.
Long description
Figure 2 is titled “Distribution of Purple Wartyback populations”. The map depicts southwestern Ontario including Lake St. Clair, Lake Erie and the southern portion of Lake Huron. This area includes the distribution of Purple Wartyback populations and shells over the years: 1996 to 2021 Live mussels, 1996 to 2021 Fresh shells or valves, and Historical (pre-1996) or recent weathered shells. First Nations, Park, and Built-up areas are also shown for reference. The map shows a scale of 60 km. An inset map is provided that depicts the location of Purple Wartyback records in relation to the province of Ontario and other Great Lakes. Live Purple Wartyback records are restricted to the Ausable, Sydenham, and Thames rivers. Historical or recent weathered shells records exists in the Ausable, Sydenham, Thames, and Detroit rivers, as well as Lake Erie in proximity to Pelee Island and surrounding islands
We would like to receive your comments on the potential impacts of adding or not adding Purple Wartyback to the List of Wildlife Species at Risk under SARA designated as Threatened. Your comments are important.
Please fill out the survey: we want to hear from you.
Before completing this survey, you may wish to review the following background information found at the links below:
- 2021 COSEWIC Assessment and Status Report on the Purple Wartyback
- Other information on the species can be found on the Species at Risk Public Registry
Thank you for completing this survey.
Contact us
Species at Risk Program
Ontario and Prairie Region
867 Lakeshore Road
Burlington, ON, L7S 1A1
Email: fwisar@dfo-mpo.gc.ca