Silver Chub (Great Lakes - Upper St. Lawrence populations)

Consultation Workbook on the proposed listing of the... Silver Chub

Proposed Risk Status: Endangered
November 2013

Silver Chub

Common Name: Silver Chub (Great Lakes - Upper St. Lawrence populations)
Scientific name: Macrhybopsis storeriana
SARA Status: Special Concern (June 2003)
COSEWIC Status:
 Endangered (May 2012)
Region: Ontario

Illustration of Silver Chub, © J. R.Tomelleri

Figure 1. A mature Silver Chub (illustration © Joseph R. Tomelleri)

The Silver Chub (Great Lakes-Upper St. Lawrence populations) has been reassessed from Special Concern to Endangered by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC).  In 2012, COSEWICsplit the populations into two separate units:  1) the Saskatchewan - Nelson River; and 2) the Great Lakes - Upper St. Lawrence. The Saskatchewan - Nelson River populations are not considered to be at risk. Based on its previous assessment, the Silver Chub is currently listed under the federal Species at Risk Act as Special Concern.  As a species of Special Concern, a management plan has been developed.  The recent change in the COSEWIC assessment will require a new listing decision under the Species at Risk Act. If the population is legally upgraded to Endangered, a recovery strategy will be developed.

General Description

The Silver Chub (Macrhybopsis storeriana) is a member of the Minnow family (Cyprinidae), and is the only species of the genus Macrhybopsis in Canada. It has the following characteristics:

  • Body is stout and thick;
  • Average length is 100 to 150 mm long; maximum length is 231 mm;
  • Coloured pale grey-green on the back, becoming silver on the sides and silvery white below; a faint lateral band is usually present;
  • Moderate-sized subterminal mouth, and a snout that projects beyond the mouth;
  • Slender barbel, usually present at the end of the maxillary (corner of the upper jaw); eye diameter is relatively large; and
  • Caudal fin is distinctly forked and lightly pigmented, except for lower three-to-four rays, which are white.

Distribution

The range of the Silver Chub extends from Lake Winnipeg, east into the Great Lakes basin, and then south, largely through the Mississippi River system from Minnesota to the Gulf of Mexico. In Canada, the Great Lakes - Upper St. Lawrence populations are found in the Great Lakes basin, limited to Lake Erie and Lake St. Clair and the extreme southern portion of Lake Huron. The Saskatchewan-Nelson River populations (reassessed in 2012 as “Not at Risk”) are found in southern Lake Winnipeg and in the Assiniboine and Red river drainages of Manitoba, North and South Dakota, and Minnesota.

Map showing distribution of Silver Chub (Great Lakes - Upper St. Lawrence populations) as described in the preceeding paragraph

Figure 2: Map of the distribution of the Silver Chub in Canada.

Habitat & Life History

In Ontario, Silver Chub is found in large lakes and connecting rivers at depths of 7.6–12 m, although it has been caught as deep as 20 m. Substrate is typically silt or sand, but the species is also sometimes associated with hard substrates, such as gravel, rubble, boulder or bedrock. It is not typically associated with aquatic vegetation. Reproduction of the Silver Chub is poorly understood. Individuals mature at age 1, and live to 3-to-4 years of age. One female can produce as many as 12,000 eggs. Silver Chub spawn in spring or early summer (May to July) at water temperatures between 19-23°C; however, there is uncertainty regarding where the species spawns and its spawning habitat requirements. In Lake Erie, the species has been observed to leave open water and move into nearshore areas in early spring, possibly to begin spawning.

Diet

The Silver Chub is a bottom feeder that uses taste and sight to locate its prey. An opportunistic forager, it feeds on aquatic insect larvae (particularly mayfly nymphs), Daphnia and other small crustaceans, and fish eggs. More recently, Silver Chub in Lake Erie have begun feeding on Zebra and Quagga mussels.

Threats

The Silver Chub was considered common in Lake Erie until the 1950s. Its rapid decline in the 1960s coincided with habitat degradation and eutrophication caused by urban and agricultural runoff. The effects included poor water quality, extensive algal blooms and depleted oxygen levels in the water. Effects on invertebrate populations reduced prey sources. Although some threats have decreased in recent years (e.g., nutrient loading in Lake Erie), many still exist. Recent threats include aquatic invasive species, baitfish harvesting and climate change. Recent studies also suggest that the population numbers have dropped substantially in the past decade, and the risk of extirpation (i.e., extinct in Canada) is high.

Similar Species

The Silver Chub is similar in appearance to the Spottail Shiner (Notropis hudsonius), the Gravel Chub (Erimystax x-punctatus) and the Hornyhead and River chubs (Nocomis biguttatus and Nocomis micropogon). Unlike the Spottail Shiner, the Silver Chub has barbels at the corners of the mouth. The Gravel Chub can be differentiated by the distinct, x-shaped marks on its body, while Hornyhead and River chubs have smaller eyes and are lighter brown in colour.

Socio-Economic Considerations

When a species is being considered for listing under the Species at Risk Act, an analysis of the benefits and costs of listing must be developed.

For more details, please contact the SARA Regional Manager.

Summary of the Cost-Benefit Analysis

The purpose of the socio-economic analysis is to examine the incremental costs and benefits to Canadians that result from listing the Silver Chub (Great Lakes - Upper St. Lawrence populations) as Endangered under the federal Species at Risk Act.

In the Great Lakes basin, Silver Chub is found in Ontario, in Lake Erie, Lake St. Clair, and the extreme southern portion of Lake Huron. Silver Chub is currently protected under Ontario’s Endangered Species Act, 2007 (ESA 2007) as a Threatened species and a provincial recovery strategy will be developed to manage the species and prevent further decline. The ESA 2007 and the Ontario Fishery Regulations prevent the intentional harvest of Silver Chub as bait, and the potential for incidental harvest of Silver Chub through the baitfish industry is low. The Silver Chub and its habitat are also protected under the Fisheries Act* and Silver Chub (both populations as a single unit) is currently listed as Special Concern under Schedule 1 of the Species at Risk Act and a management plan was completed for the species in 2010. Silver Chub also benefits from the recovery strategy for the Essex-Erie region (an area that includes western Lake Erie, the Detroit River and the southern shores of Lake St. Clair).

When a species is listed as Endangered under the Species at Risk Act, the general prohibitions to protect the species take effect. A recovery strategy and an action plan are prepared, and critical habitat is protected once identified and a ministerial order has been put in place. Permits/agreements authorizing activities affecting a listed wildlife species can be entered into, and there can be exemptions for activities that are permitted by a recovery strategy or action plan.

As the Silver Chub is not fished, the general prohibitions under the Species at Risk Act are not anticipated to have an impact. The Silver Chub and its habitat currently receive protection under Ontario’s Endangered Species Act and the cost of developing the federal recovery strategy is anticipated to be negligible. Consequently, listing the Silver Chub as Endangered under the Species at Risk Act is anticipated to result in low or negligible socio-economic impacts.

* NOTE: In 2012, amendments to the Fisheries Act were passed into law, and were in force as of November 25, 2013. As the Silver Chub’s distribution currently overlaps with those fisheries protected under the Fisheries Act (i.e., commercial, recreational or Aboriginal fisheries), its habitat is consequently protected.

Let us know what you think

This workbook is part of a public consultation process to get your feedback on whether to add the Silver Chub to the Species at Risk Act (SARA) List.  Your answers to the following questions will help determine the federal Government’s decision.

It is important that you understand how the proposed listing can help to protect and recover Silver Chub, and how it may impact on your activities.  As a legally threatened species, automatic prohibitions of SARA would apply.

These prohibitions make it illegal to kill, harm, harass, possess, collect, buy, sell or trade an Extirpated, Endangered or Threatened species. It is also generally illegal to damage or destroy the places these species live. These prohibitions do not apply to species of Special Concern.

If a wildlife species is added to the SARA List as an Extirpated, Endangered or Threatened species, the federal government must prepare a strategy for its recovery. The recovery strategy outlines known threats to the species, identifies the habitat it needs to survive, and highlights gaps in knowledge. It also sets a goal for the species’ recovery.

A recovery strategy must be completed within two years if it is listed as Threatened.  Note that the recovery strategy process will also involve further consultation.

How to use this questionnaire:

Please provide your responses to the questions on the following pages. We welcome feedback from all individuals, regardless of whether you are involved in activities that may or may not be affected by this listing.

Please also use extra sheets to expand your answers as needed.

Please return your completed comments by March 31, 2014 to the following federal Species at Risk office:

SARA Regional Manager
Fisheries and Oceans Canada
501 University Crescent
Winnipeg, MB R3T 2N6
Email: fwisar@dfo-mpo.gc.ca
Toll-free: 1-866-538-1609

Or provide comments directly through the SARA Registry.

 

The information you provide is important.
We appreciate the time and effort you take to complete this questionnaire.

Proposed SARA Listing of Silver Chub

1. Are you in favour of listing the Silver Chub as a Threatened species?

checkbox Yes
checkbox No
checkbox Undecided

Please explain your decision.


 


 

2. The following questions provide us with information about how you value the Silver Chub. Please choose the response that best describes your opinion.

a. I believe it is important to maintain the Plains Minnow so that future generations can enjoy them.

checkbox Strongly disagree   checkbox  Disagree   checkbox  Neutral   checkbox  Agree   checkbox  Strongly agree

b. I believe the Silver Chub plays a significant role in maintaining a healthy ecosystem.

checkbox Strongly disagree   checkbox  Disagree   checkbox  Neutral   checkbox  Agree   checkbox  Strongly agree

c. I believe the Silver Chub has social and/or cultural significance to my community.

checkbox Strongly disagree   checkbox  Disagree   checkbox  Neutral   checkbox  Agree   checkbox  Strongly agree

d. I believe the Silver Chub is an important part of our national heritage.

checkbox Strongly disagree   checkbox  Disagree   checkbox  Neutral   checkbox  Agree   checkbox  Strongly agree

e. I believe the Silver Chub is an important subsistence food source.

checkbox Strongly disagree   checkbox  Disagree   checkbox  Neutral   checkbox  Agree   checkbox  Strongly agree

f. I believe the Silver Chub has economic value (recreational or commercial values).

checkbox Strongly disagree   checkbox  Disagree   checkbox  Neutral   checkbox  Agree   checkbox  Strongly agree

g. I believe the Silver Chub provides job opportunities (e.g. tourism) to the local economy.

checkbox Strongly disagree   checkbox  Disagree   checkbox  Neutral   checkbox  Agree   checkbox  Strongly agree

h. Others? (please specify)


 


 

3. The following questions provides us with information about how you perceive the following threats to the Silver Chub. Please choose the response that best describes your opinion.

a.  Farming/ Agriculture: Threats to species includes the modification of habitat (e.g. pollution, sedimentation, salinization, water turbidity, reduction in oxygen levels, drainage works, and changes in water levels due to irrigation).

checkbox Very low    checkbox Low    checkbox Moderate    checkbox High    checkbox Very high

b.  Ecosystem modification (Altered flow regimes): Water management and alteration of natural flow patterns can modify habitat areas and migration routes.

checkbox Very low    checkbox Low    checkbox Moderate    checkbox High    checkbox Very high

c.  Ecosystem modification (Urban development and land use practices): Damage to habitat and poor water quality resulting from urban development and agricultural practices.

checkbox Very low    checkbox Low    checkbox Moderate    checkbox High    checkbox Very high

d. Invasive species: Threats to species includes competition with native wild native populations for resources and shelter. 

checkbox Very low    checkbox Low    checkbox Moderate    checkbox High    checkbox Very high

e. Climate change: Threats to species include the modification of habitats (e.g. water temperature, salinity, distribution of ice, breeding and feeding grounds); negative impacts on reproduction seasons; modification of food chain flows (e.g. plankton species). (*Silver Chub in Ontario are believed to be at the northern extent of their range)

checkbox Very low    checkbox Low    checkbox Moderate    checkbox High    checkbox Very high

f. Other: Do you have any other comments about other possible threats to the Silver Chub that may threaten their survival or recovery?


 

4. The following questions provide us with information about how the listing of the Silver Chub could impact you or your activities.

a. Based on what you have learned about the Species at Risk Act, do you think adding the Silver Chub to the SARA List would impact your activites?

checkbox Not at all    checkbox Not much    checkbox Don’t know    checkbox Yes, a bit    checkbox Yes, a lot

Why?


 


 

5. Do you feel that the listing of the Plains Minnow will have economic, social and/or ceremonial impacts to you?

checkbox Not at all    checkbox Not much    checkbox Don’t know    checkbox Yes, a bit    checkbox Yes, a lot

In what way?


 


 

6. If your activity is impacted by listing the Plains Minnow, would you be willing to change your activity?

checkbox Not at all    checkbox Not much    checkbox Don’t know    checkbox Yes, a bit    checkbox Yes, a lot

How?


 


 

7. All Canadian households, as well as industry, pay for the protection of all legally listed species under SARA. How much would you be willing to pay (in Canadian dollars) each year for the conservation, protection and recovery efforts for the Silver Chub?

checkbox $0   checkbox $10   checkbox $20   checkbox $50   checkbox $100   checkbox more than $100

 

This last section is personal and confidential. We recognize that it is not insignificant to ask people to share personal information. To that end, we will adhere to strict ethical standards of privacy in doing further research with this information. Unless directed otherwise by the respondents, no information will be reported that can be attributed to any particular individual.

9. In what capacity are you completing this questionnaire?

checkbox  Individual    checkbox  Representative of a group

 

10. Where do you live?

checkbox British Columbia
checkbox Alberta
checkbox Saskatchewan
checkbox Manitoba
checkbox Quebec
checkbox Nova Scotia
checkbox New Brunswick
checkbox Prince Edward Island
checkbox Newfoundland & Labrador
checkbox Yukon
checkbox Northwest Territories
checkbox Nunavut
checkbox Ontario

 

11. Which sector do you represent?

checkbox Aboriginal community
checkbox Aboriginal organization
checkbox Academic community
checkbox Agriculture / Farming
checkbox Environmental organization
checkbox Fishing – aquaculture
checkbox Fishing – commercial
checkbox Fishing – recreational
checkbox Forestry
checkbox Government (specify level)
checkbox Hydro-electric
checkbox Manufacturing
checkbox Oil and gas
checkbox Professional services

checkbox Other ____________________

 

12. What is your age?

checkbox  Under 20
checkbox  20 - 29
checkbox  30 - 39
checkbox  40 - 49
checkbox  50 - 59
checkbox  60 or over

Please add any other comments or concerns (add additional sheets if necessary) that you would like to have considered.


 


 


 


 

Thank you for taking the time to complete this survey.