Western Silvery Minnow
Scientific Name: Hybognathus argyritis
Taxonomy Group: Fishes
COSEWIC Range: Alberta
COSEWIC Assessment Date and Status Change: November 2017
COSEWIC Status: Threatened
COSEWIC Status Criteria: Meets Endangered, B1ab(iii)+2ab(iii), but designated Threatened, B1ab(iii)+2ab(iii), because the species is not at risk of imminent extirpation.
COSEWIC Reason for Designation: This is a small-bodied minnow species that is restricted in Canada to the Milk River of southern Alberta. It is a habitat specialist found in shallow zones of turbid prairie waters with high seasonal flow variability and unstable fine sediments. It is threatened by flow management resulting from water diversions in the US and a warming and drying climate with negative impacts on habitat quantity and quality. Despite meeting criteria for Endangered, the severity of the threats is uncertain and there is no evidence of a decline in abundance since the previous assessment.
COSEWIC History of Status Designation: Designated Special Concern in April 1997. Status re-examined and designated Threatened in November 2001. Status re-examined and designated Endangered in April 2008. Status re-examined and designated Threatened in November 2017.
SARA Status: Schedule 1, Threatened
Date of Listing (yyyy-mm-dd): 2003-06-05
Please note that this information is provided for general information purposes only. For the most up to date and accurate list of species listed under the Species at Risk Act, please see the Justice Laws Website.
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Image of Western Silvery Minnow
The Western Silvery Minnow (Hybognathus argyritis) is a member of the Minnow family, Cyprinidae, and has the following characteristics:
Yellow with silver sides, a white belly and a faint, broad, mid-dorsal stripe;
Elongated body with a stout, narrow section just before the tail;
A short, bluntly triangular head with a rounded snout that overhangs the subterminal mouth;
The dorsal, anal and pelvic fins each contain eight rays;
Pectoral fins are relatively short with 15 or 16 rays;
Caudal fin is forked; and
Averages 76 to 125 mm in length.
Distribution and Population
In Canada, the Western Silvery Minnow is endemic in southern Alberta, and is found only in the Milk River. In the United States, this fish occurs in the Mississippi River Basin, from the mouth of the Ohio River north to the Missouri Basin and Milk River in Montana.
The Western Silvery Minnow is typically found in the plains in quiet water with low velocity, such as in the backwaters and pools of larger streams. It prefers sandy bottoms but frequents areas of gravel, muck or debris-covered substrate.
Spawning is believed to occur in May in shallow waters. Females begin spawning in their first year; males do not spawn until two years of age. The eggs are 1 mm in size, non-adhesive and hatch within a week in temperatures ranging from 13? to 20?C. This species is known to form large schools of 50 to 100 fish. The Western Silvery Minnow has a lifespan of up to four years. The diet of the Western Silvery Minnow is believed to consist of benthic diatoms and algae, and other organic matter originating from bottom detritus.
Given its limited distribution, the survival of the Western Silvery Minnow in Canada may be particularly susceptible to a number of threats including siltation, changes in water flows and levels, prolonged drought and introduced pollutants.
The Western Silvery Minnow is protected under the federal Species at Risk Act (SARA).
More information about SARA, including how it protects individual species, is available in the Species at Risk Act: A Guide.
The federal Fisheries Act prohibits destruction of fish habitat.
Provincial and Territorial Protection
To know if this species is protected by provincial or territorial laws, consult the provinces' and territories' websites.
Status of Recovery Planning
Recovery Strategies :
Name Recovery Strategy for the Western Silvery Minnow (Hybognathus argyritis) in Canada
Status Final posting on SAR registry
Western Silvery Minnow Recovery Team
Terry Clayton - Chair/Contact - Other
Phone: 403-382-4362 Fax: 403-381-5723 Send Email
Shane Petry - Chair/Contact - Fisheries and Oceans Canada
Phone: 403-394-2926 Send Email
PLEASE NOTE: Not all COSEWIC reports are currently available on the SARA Public Registry. Most of the reports not yet available are status reports for species assessed by COSEWIC prior to May 2002. Other COSEWIC reports not yet available may include those species assessed as Extinct, Data Deficient or Not at Risk. In the meantime, they are available on request from the COSEWIC Secretariat.
30 record(s) found.
Reports on the Progress of Recovery Document Implementation
In June 2003, the Western Silvery Minnow (Hybognathus argyritis) was officially listed on Schedule 1 of the federal Species at Risk Act (SARA) as Threatened, when the SARA came into force. The Recovery Strategy for Western Silvery Minnow (Hybognathus argyritis) in Canada (hereafter referred to as the “Recovery Strategy”) was posted on the Species at Risk Public Registry in 2008. The following document fulfills Fisheries and Oceans Canada’s (DFO) commitment to report every five years on the progress of recovery strategy implementation and covers the period from 2008 to 2013.
COSEWIC Status Reports
The Western Silvery Minnow (Hybognathus argyritis) is a small fish belonging to the Cyprinidae family. It has an elongated body, triangular head, and small subterminal mouth. Its sides are bright silver, fading to brownish yellow dorsally and white ventrally. This species averages 80-85 mm in fork length (FL) and grows to a maximum of ~150 mm FL. A single population of Western Silvery Minnow exists in Canada. The species is native to Alberta and was first sampled in the province in 1961.
Note: This COSEWIC assessment was received by the Minister on October 15th, 2018.
The average size of the Western Silvery Minnow (Hybognathus argyritis) is approximately 76 mm in length with a maximum length of 125 mm. The body is elongate, moderately compressed laterally and has a stout caudal peduncle. The head is short, bluntly triangular with a moderately large eye; the snout is rounded and overhangs the mouth which is subterminal. There is one dorsal fin with eight rays originating slightly in advance of the origin of the pelvic fins which have eight rays, but sometimes seven. The caudal fin is forked; the anal fin originates behind the posterior margin of the depressed dorsal and usually has eight rays, sometimes nine; the pectoral fins are relatively short with 15 or 16 rays.
The western silvery minnow (Hybognathus argyritis Girard, 1856) is a small cyprinid and is one of the four species of the genus Hybognathus occurring in Canada. It was first discovered in the Milk River in Montana by Girard in 1856. Scott and Crossman later treated the species as a subspecies (H. nuchalis nuchalis) of the central silvery minnow (H. nuchalis Agassiz, 1855). Currently, the species has again been recognized as the western silvery minnow (H. argyritis). This decision was made based on differences in the shape of the basioccipital process between species and has been accepted by the American Fisheries Society.
This small minnow species is restricted to the Milk River in Southern Alberta, a region characterized by drought conditions of increasing frequency and severity. While the future of flow regimes associated with the St. Mary’s diversion canal and proposed water storage projects are uncertain, consequences of these activities have the potential to significantly affect the survival of the species. Rescue effect from U.S. populations is not possible.
This is a small-bodied minnow species that is restricted in Canada to the Milk River of southern Alberta. It is a habitat specialist found in shallow zones of turbid prairie waters with high seasonal flow variability and unstable fine sediments. It is threatened by flow management resulting from water diversions in the US and a warming and drying climate with negative impacts on habitat quantity and quality. Despite meeting criteria for Endangered, the severity of the threats is uncertain and there is no evidence of a decline in abundance since the previous assessment.
In June 2003 when the Species at Risk Act (SARA) came into force, the Western Silvery Minnow (Hybognathus argyritis) was officially listed on Schedule 1 of the SARA as “Threatened”, requiring the completion of a recovery strategy within four years. Similarly, the Province of Alberta has listed the Western Silvery Minnow as “Threatened” under Alberta’s Wildlife Act and has completed a recovery plan for the species.
This action plan addresses two species found in the Milk River and St. Mary River drainage basins, Alberta, and follows a multi-species approach to protect and maintain self-sustaining populations of both species. Both the St. Mary and Milk River drainage basins originate in Montana along the eastern slopes of the Rocky Mountains and flow north and north east, respectively, into Alberta. This action plan builds on the recovery strategies of the Rocky Mountain Sculpin (Eastslope populations) and the Western Silvery Minnow. In Alberta, the Rocky Mountain Sculpin (Cottus sp.) is found in the St. Mary River drainage and the Milk River drainage and the Western Silvery Minnow (Hybognathus argyritis) is found in the Milk River drainage. Both species are listed as Threatened under the federal Species at Risk Act.
Her Excellency the Governor General in Council, on the recommendation of the Minister of the Environment, acknowledges receipt, on the making of this Order, of the assessments conducted pursuant to subsection 23(1) of the Species at Risk Act by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) with respect to the species set out in the annexed schedule.
COSEWIC Annual Reports
2008 Annual Report to the The Minister of the Environment and the Canadian Endangered Species Conservation Council (CESCC) from the Committee on the Status of Endangered Wildlife in Canada.
Over the past year COSEWIC assessed a total of 90 wildlife species and 11 of these were assigned a status of Not at Risk. Of these 90, COSEWIC re-examined the status of 38 wildlife species; of these, the majority (87%) were reassessed at the same or lower level of risk. To date and with the submission of this report, COSEWIC’s assessments now include 771 wildlife species in various risk categories including 338 Endangered, 183 Threatened, 228 Special Concern, and 22 Extirpated (i.e. no longer found in the wild in Canada). In addition, 18 wildlife species have been assessed as Extinct, and a total of 59 wildlife species have also been designated as Data Deficient and 197 have been assessed and assigned Not at Risk status.
Permits and Related Agreements
A failed culvert will be replaced with a clear span bridge with abutments above the high water mark in an unnamed tributary of the Berland River near Fox Creek, Alberta. Incidental capture of Rainbow Trout (Oncorhynchus mykiss) (Athabasca River populations), Bull Trout (Salvelinus confluentus) (Western Arctic populations), Rocky Mountain Sculpin (Cottus sp.) (Eastslope populations), and Western Silvery Minnow (Hybognathus argyritis), may occur during site isolation and fish relocation. The access road associated with the failed culvert was acquired by Cenovus Energy Inc. from ConocoPhillips Canada on May 17th of 2017. Cenovus Energy Inc. intends to correct the failed crossing by installing a clear span bridge and restoring the watercourse's bed and banks to be in compliance with provincial regulations.
The objectives of the activities covered by the permit include: 1. To conduct a morphometric analysis on Mountain Sucker (Catostomus platyrhynchus) (Milk River populations) collected from the locations listed on the permit; 2. To conduct stable isotope analysis on the fish community in the Milk River and Lee Creek; and, 3. To assess potential impacts of flow augmentation on Mountain Sucker vital rates using a ramp-Ucrit test and a burst test in a swim tunnel.
The activities authorized by the permit consist of: 1. The capture of the species listed on the permit from the waterbodies listed on the permit via electrofishing and seine netting; 2. The handling of the species listed on the permit for the purposes of identification and processing (count, measure, fin clips, swim tests, and photograph). Fin clips will be taken from a maximum of 10 each per site (three sites total), of Western Silvery Minnow (Hybognathus argyritis), Rocky Mountain Sculpin (Cottus sp.), and Bull Trout (Salvelinus confluentus) (Saskatchewan - Nelson Rivers populations) (Bull Trout from this point forward). With the exception of a lethal sub-sample (see following condition), all fishes captured will be returned alive to the location of capture; 3. The collection of a lethal sub-sample of the species listed on the permit (a maximum of 360 Mountain Sucker, and a maximum of 15 each of Rocky Mountain Sculpin, Western Silvery Minnow, and Bull Trout) to conduct a stable isotope analysis; and, 4. The transport and storage of preserved tissue samples of the species listed on this permit, and any species listed on this permit killed incidentally or for testing purposes.
The objectives of the activities covered by this permit are to conduct fish surveys in the Milk River watershed, Alberta, to monitor the effects of low water levels that have occurred as a result of a failure on the St. Mary Canal, the main water source for the Milk River. Mountain Sucker (Catostomus platyrhynchus) (Milk River populations), Rocky Mountain Sculpin (Cottus sp.) (Eastslope populations), and Western Silvery Minnow (Hybognathus argyritis) may be captured during this work.
The activities authorized by this permit consist of: 1. The capture of the species listed above from the Milk River watershed, using a combination of boat electrofishing, backpack electrofishing, beach seining, and minnow trapping. The choice of sampling gear will be dependent on site conditions; 2. The handling of the species listed above for the purposes of identification (count, measure, and photograph). With the exception of vouchers that may be retained to confirm identification, all fishes will be released alive after processing; and, 3. The possession and transport of the species listed on this permit found deceased as a result of
low water levels, or killed incidentally as a result of sampling and/or processing, or for
The objective of the activities covered by the permit is to conduct surveys for Western Silvery Minnow (Hybognathus argyritis) within the Milk River watershed in southern Alberta. Rocky Mountain Sculpin (Cottus sp.) and Mountain Sucker (Catostomus platyrhynchus) (Milk River populations) (Mountain Sucker from this point forward) may also be captured during this work.
The activities authorized by the permit consist of: 1. The capture of Western Silvery Minnow, Rocky Mountain Sculpin, and Mountain Sucker, using a seine net, from 17 sample locations listed on the permit; 2. The handling of Western Silvery Minnow, Rocky Mountain Sculpin, and Mountain Sucker for the purposes of identification (count, measure, and photograph). With the exception of vouchers that may be retained to confirm identification, all fishes will be released alive after processing; and, 3. The possession and transport of Western Silvery Minnow, Rocky Mountain Sculpin, and/or Mountain Sucker killed incidentally as a result of sampling, processing, or for vouchering purposes.
The objective of the work is to capture 15 live Western Silvery Minnow specimens for live tanks at the provincially operated Bow Habitat Station in Calgary Alberta.
The purpose of this project is to capture 18 specimens of Western Silvery Minnow and Rocky Mountain Sculpin for the Bow Habitat Station in Calgary. They will be used to educate the public on the status and importance of the Western Silvery Minnow and Rocky Mountain Sculpin, as well as recovery efforts and provision of information on how to help the recovery effort. These objectives are consistent with the joint (federal and provincial) recovery strategy actions.
The objectives of the work are to capture up to 20 Western Silvery Minnow and up to 15 Rocky Mountain Sculpin (Alberta) for extension programs and a DFO genomics project. It is anticipated that the genomics project will eventually lead to the development of genetic marks that can be used to monitor trade shipments.
The purpose of the permit is to conduct a directed study on Western Silvery Minnow designed to answer research needs identified in the Recovery Strategy (clarifying life history and habitat requirements as well as population monitoring for the species).
The purpose of the permit is to conduct a multi-pass capture mark recapture electrofishing survey will be used to estimate the population of Sauger in three reaches of the Milk River to estimate the abundance of the species. This information is required by Alberta Environment and Sustainable Resource Development to update the current status of Sauger in the Milk River.
The purpose of the permit is to 1) define habitat preference of Western Silvery Minnow in the Milk River, 2) measure changes in available preferred habitat during augmented flow period (May-September) and natural flow period (October to April) and 3) measure swimming ability of Western Silvery Minnow.
Observations of habitat use by the Western Silvery Minnow will be undertaken in a section of the river accessible only by canoe. Minimal disturbance to the Western Silvery Minnow is expected and zero impact on habitat. No fish will be sacrificed.
Field collections will be done with a beach seine. Presence/absence data will be collected, plus enumeration of species. Sampling (or subsampling if high numbers are encountered) of all fish species will be done for fork and total length. Any backwater or sheltered habitats, such as confluence areas with ephemeral creeks, will be seined if depth is suitable. Locations seined will be identified using GPS.
This research is a survey to confirm where Western Silvery Minnows are currently found and where they are most abundant; and to describe the type of habitat that supports Western Silvery Minnows.
The goal of this work is to observe Western Silvery Minnow habitat and to survey the area for the presence of Western Silvery Minnows. This will help define the range of the species and identify the type of habitat where the species is found.
The goal of this work is to determine which types of habitat are utilized by Western Silvery Minnow adults and juveniles during different times of the year. Fish will be collected and released unharmed after being counted, measured, and sampled for their DNA.
This research is a study of the distribution, abundance, habitat use, diet, genetics and life history of the Western Silvery Minnow, Carmine Shiner, and Eastslope Sculpin.
This research is a comprehensive survey of Ontario fish communities that will aid in the recovery of species at risk by assessing their current geographic distribution and habitat associations.
This permit includes all the aquatic fish and mussel species listed for protection on Schedule 1 that are found in Ontario.
Consultations concerning the changing of the species SARA status are part of the Government’s commitment to encourage public participation in programs designed to protect Canadian plants and animals and their habitat. The Western Silvery Minnow has been recently been reassessed by COSEWIC, and has had its designation changed from Threatened to Endangered. We welcome your comments about whether the Western Silvery Minnow should have its SARA status changed to Endangered.
Critical Habitat Orders
The Western Silvery Minnow (Hybognathus argyritis) is a small cyprinid species native to northwestern North America. In Canada, the Western Silvery Minnow has only been confirmed in the Milk River in southern Alberta. In November 2001, the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) assessed the status of the Western Silvery Minnow and classified the species as a threatened species. In June 2003, the Western Silvery Minnow was listed as threatened in Part 3 of Schedule 1 to the Species at Risk Act (SARA). Following an updated status report and reassessment by COSEWIC in April 2008, the COSEWIC status of the Western Silvery Minnow changed from threatened to endangered. However, in November 2017, COSEWIC reassessed the Western Silvery Minnow and changed the status back to threatened based on new knowledge of its habitat requirements, trends, biology and threats. The species meets the criteria for endangered, but was assessed as threatened because there is no evidence of decline in abundance and there is uncertainty in the severity of threats
Recovery Document Posting Plans
Under the Species at Risk Act (SARA), the competent Minister(s) must prepare a recovery strategy within one year of listing a species on Schedule 1 of SARA as endangered and within two years of listing a species as extirpated or threatened. A management plan must be prepared within three years for a species listed as special concern.
Fisheries and Oceans Canada (DFO) is accountable for 111 of the 518 species listed under SARA. As of February 2016, proposed recovery strategies, management plans and action plans for 57 of those species have not yet been posted to the Species at Risk Public Registry. An additional 23 aquatic species have proposed management or action plans coming due in the future.
The following outlines the Department’s plan for posting proposed documents for 64 species on the Species at Risk Public Registry. The Department has a plan to post recovery strategies for 9 species, management plans for 13 species, and action plans for 42 species over the next year.
Original publication of the Recovery Document Posting Plan: 2016-05-02