Warning This Web page has been archived on the Web.

Archived Content

Information identified as archived on the Web is for reference, research or recordkeeping purposes. It has not been altered or updated after the date of archiving. Web pages that are archived on the Web are not subject to the Government of Canada Web Standards, as per the Policy on Communications and Federal Identity.

Skip booklet index and go to page content

Recovery strategy for the Pugnose Shiner (Notropis anogenus) in Canada

1. Background

1.1 Species Assessment Information from the Committee on the Status of Endangered Wildlife in Canada (COSEWIC)

Common name (population): Pugnose Shiner
Scientific name: Notropis anogenus
Current COSEWIC status & year of designation: Endangered 2002
Canadian occurrence: Ontario
Reason for designation: The Pugnose Shiner has a limited, fragmented Canadian distribution, being found only in Ontario where it is subject to declining habitat quality. The isolated nature of its preferred habitat may prevent connectivity of fragmented populations and may prevent gene flow between existing populations and inhibit re-colonization of other suitable habitats.
COSEWIC status history: Designated Special Concern in April 1985. Status re-examined and designated Endangered in November 2002.

1.2 Description

The Pugnose Shiner (Notropis anogenus Forbes, 1885) (Figure 1) is a slender, moderately compressed, silvery minnow with a lateral black stripe, and a blunt snout ending in an extremely small, upturned, mouth (Becker 1983; Holm and Mandrak 2002). Total length (TL) is approximately 50 mm for males and 60 mm for females (Holm and Mandrak 2002), but individuals have been caught as large as 72 mm. Overall colouration is silvery with pale yellow tints on back and silvery below This species is sexually dimorphic during the breeding season when the males takes on a bright golden colouration (Smith 1985). The dark lateral band extends from the snout through the eye to the end of the caudal peduncle, terminating in a small dark wedge-shaped caudal spot. All fins are transparent and, unlike other Notropis spp., the peritoneum (lining of abdominal cavity) is black (Holm and Mandrak 2002). The mouth is positioned almost vertical to the body axis (Becker 1983) and is the distinguishing feature that separates the Pugnose Shiner from other species in the black-lined shiner group, especially when they are age-0 juveniles (Leslie and Timmins 2002). This species is most similar in appearance to the Blackchin Shiner (N. heterodon), which is distinguished from the Pugnose Shiner by its larger mouth (Holm and Mandrak 2002). The Pugnose Shiner is also similar in appearance to the Pugnose Minnow (Opsopoeodus emiliae) and Bridle Shiner (N. bifrenatus). The Pugnose Minnow can be distinguished from the Pugnose Shiner by dark areas on the dorsal fin, crosshatched areas on the upper surface and nine dorsal rays (Pugnose Shiner typically has eight dorsal rays) (Page and Burr 1991; Scott and Crossman 1998). The Bridle Shiner is distinguished from the Pugnose Shiner by its larger, upturned mouth, seven anal rays and incomplete lateral line (Page and Burr 1991, Scott and Crossman 1998).

Figure 1. Pugnose Shiner (Notropis anogenus)
Illustration by Ellen Edmonson, New York State Department of Environmental Conservation.

Pugnose shiner (see long description below).
Long description of Figure

Figure 1 is captioned “Pugnose Shiner (Notropis anogenus)”. It is a coloured illustration by Ellen Edmonson, New York State Department of Environmental Conservation, from the side, of a Pugnose Shiner.

1.3 Populations and distribution

Global range

The Pugnose Shiner has a limited and disjunct distribution in North America (Figure 2). It is found in the upper Mississippi River, Red River of the North and the Great Lakes basins (Holm and Mandrak 2002). It is found in several tributaries of the Mississippi River in Illinois, Minnesota and Wisconsin, and in the upper Red River of the North drainage of Minnesota and North Dakota (Holm and Mandrak 2002). Within the Great Lakes basin, the Pugnose Shiner is known from tributaries of lakes Huron, Michigan, St. Clair, Erie, eastern Lake Ontario and the upper St. Lawrence River (Holm and Mandrak 2002). Recent declines have been observed across its distribution, although this species has not been monitored sufficiently to determine population trends throughout its range (NatureServe 2009).

Figure 2. North American distribution of the Pugnose Shiner, modified from Page and Burr (1991)

North American distribution of the Pugnose Shiner (see long description below).
Long description of Figure 2

Figure 2 is captioned “North American distribution of the Pugnose Shiner, modified from Page and Burr (1991)”. The figure is a line drawing of a map of the Great Lakes area and surrounding regions of the United States and Canada. A scale is provided. The map shows two major areas identified with Pugnose Shiner populations as well as several disjunct smaller areas. These areas are shaded in grey and include tributaries of the Mississippi River in Illinois, Minnesota and Wisconsin, and the upper Red River of the North drainage of Minnesota and North Dakota and, within the Great Lakes basin, tributaries of lakes Huron, Michigan, St. Clair, Erie, eastern Lake Ontario and the upper St. Lawrence River. The map has been modified from “A Field Guide to Freshwater Fishes of North America North of Mexico” (Page and Burr 1991).

Canadian range

In Canada, this species has only been recorded south of 46 degrees latitude (Leslie and Timmins 2002) in four main areas of Ontario (Figure 3a, 3b): southern Lake Huron, Lake St. Clair, Lake Erie, and eastern Lake Ontario/upper St. Lawrence River.

The species is considered to be extant in the following areas:

  • Teeswater River (Saugeen watershed) (Fisheries and Oceans Canada (DFO), unpublished data),
  • Old Ausable Channel (Ausable River Recovery Team (ARRT) 2006),
  • Mouth Lake (DFO, unpublished data),
  • Canard River (Royal Ontario Museum, Toronto, ON, unpublished data),
  • Lake St. Clair (including Walpole Island) (Holm and Mandrak 2002) and two of its tributaries (Whitebread Drain/Grape Run Drain and Little Bear Creek) (Mandrak et al. 2006b; Royal Ontario Museum, Toronto, ON, unpublished data),
  • St. Clair NWA (Bouvier et al. 2010),
  • Long Point Bay/Big Creek (including Long Point NWA (both Thoroughfare Point Unit and Long Point Unit) and Big Creek NWA (Big Creek Unit only) - from this point forward, the phrase Long Point Bay/Big Creek includes reference to the NWAs) (Marson et al. 2009),
  • Wellers Bay (including all occasionally exposed lands of Wellers Bay National Wildlife Area lying between the high water mark and the water’s edge of Wellers Bay, which forms the boundary of Wellers Bay NWA which varies with water level fluctuations of Lake Ontario – from this point forward, the phrase Wellers Bay includes reference to the NWAs) (DFO, unpublished data),
  • West Lake (DFO, unpublished data),
  • East Lake (DFO, unpublished data),
  • Waupoos Bay, (DFO, unpublished data) and,
  • St. Lawrence River (from Eastview to Mallorytown Landing, including the St. Lawrence Islands National Park) (Carlson 1997; Mandrak et al. 2006a; J. Van Wieren, unpublished data).

Pugnose Shiner was last captured from Gananoque River in 1935, Point Pelee National Park in 1941 and Rondeau Bay in 1963 (Holm and Mandrak 2002).

Scott and Crossman (1998) described the Canadian range of Pugnose Shiner as diminishing and surmised that it probably occurred historically between the two widely separated areas where it is now found, along the northern shores of lakes Erie and Ontario.

Percentage of global distribution in Canada

Less than 10% of the species’ global range occurs in Canada (ARRT 2006).

Distribution trend

The change in the distribution of Pugnose Shiner is difficult to assess due to a lack of data, which has been attributed to the species’ small size, difficulties with field identification and a lack of time-series data (Holm and Mandrak 2002). Three Canadian occurrences are believed to have been lost over the last 50 years (Gananoque River, Point Pelee National Park and Rondeau Bay); however, Pugnose Shiner has been found at a number of new locations across its range, including the Mouth Lake, Teeswater River, Little Bear Creek and Whitebread Drain, Wellers Bay, West Lake, East Lake and Waupoos Bay, as well as numerous locations within the stretch of the St. Lawrence River (approximately 45 km long) between Eastview and Mallorytown Landing, including the St. Lawrence Islands National Park.

Figure 3a. Distribution of Pugnose Shiner in southwestern Ontario

Distribution of Pugnose Shiner in southwestern Ontario (see long description below).
Long description of Figure

Figure 3a is captioned “Distribution of Pugnose Shiner in southwestern Ontario”. This is a map of southwestern Ontario with an inset at the top left of the map showing the geographical location of this map on a larger scale map. A legend and scale are provided. The legend provides symbols denoting years of capture (2001–2010, 1991–2000, 1981–1990, and 1935–1980) as well as for Parks, First Nations, and Built-up Areas. Individual data points are identified by year of capture. The map shows that, for the time period 2001–2010, Pugnose Shiner was found at, or near, the Old Ausable Channel along the Lake Huron shoreline, the Teeswater River, in areas in, or near, the Walpole Island Indian Reserve along the Lake St. Clair shoreline and the mouth of the St. Clair River, and at, or near, Long Point Provincial Park and Turkey Point Provincial Park. Distribution for the time period 1991–2000 was in, or near, the Walpole Island Indian Reserve along the Lake St. Clair shoreline and the mouth of the St. Clair River, with several data points in Long Point Provincial Park and along the Lake Huron shoreline near the Old Ausable Channel. Data points for the 1981–1990 time period are scattered along the shoreline of Lake St. Clair, south of Walpole Island Indian Reserve. Older data points from 1935–1980 are shown at Point Pelee National Park, and Rondeau Provincial Park.

Figure 3b. Distribution of Pugnose Shiner in southeastern Ontario

Distribution of Pugnose Shiner in southeastern Ontario (see long description below).
Long description of Figure

Figure 3b is captioned “Distribution of Pugnose Shiner in southeastern Ontario”. This is a map of the eastern end of Lake Ontario with an inset at the top left of the map showing the geographical location of this map on a larger scale map. A legend and scale are provided. The legend provides symbols denoting years of capture (2001–2010, 1991–2000, 1981–1990, and 1935–1980) as well as for Parks, First Nations, and Built-up Areas. Individual data points are identified by year of capture. The map shows that, for the time period 2001–2010, Pugnose Shiner was found in the in the upper St. Lawrence River, upstream of Mallorytown Landing and at, or near Gananoque, Eastview, Waupoos Bay, West Lake, East Lake, and Sand Banks Provincial Park. Older data points from 1935–1980 are shown at the mouth of the Gananoque River.

Global population size and status

Global population estimates for Pugnose Shiner are not available; however, it is considered generally rare but sometimes locally abundant (NatureServe 2009). It is listed as globally vulnerable; extirpated in Ohio; critically imperilled in Illinois, Indiana, Iowa, New York and North Dakota; and, vulnerable in Michigan and Minnesota (NatureServe 2009). National and sub-national status ranks are summarized in Table 1.

Table 1. Canadian and U.S. national and sub-national status ranks for Pugnose Shiner
Rank levelRankTable noteaJurisdictions
National (N)
N2/N3
Canada
National (N)
N3
United States
Sub-national (S): Canada
S2
Ontario
Sub-national (S): United States
S1
Illinois, Indiana, Iowa, New York, North Dakota
Sub-national (S): United States
S2
Wisconsin
Sub-national (S): United States
S3
Michigan, Minnesota
Sub-national (S): United States
SX
Ohio

source: NatureServe 2009

Table notes

Table 1 note a

Refer to Appendix 1 for definition of status rankings.

Return to table noteareferrer

Canadian population size and status

The status of Pugnose Shiner populations in Canada was assessed by Bouvier et al. (2010) (Table 2). Populations were ranked with respect to abundance and trajectory. Population abundance and trajectory were then combined to determine the population status. A certainty level was also assigned to the population status, which reflected the lowest level of certainty associated with either population abundance or trajectory. Refer to Bouvier et al. (2010) for further details on the methodology.

Table 2. Population status and associated certainty of individual Pugnose Shiner populations in Canada
DrainagePopulationtable notebPopulation statusCertaintytable notec
Lake HuronTeeswater RiverUnknown
3
Lake HuronOld Ausable ChannelFair
2
Lake HuronMouth Lakedtable notedUnknown
3
Lake St. ClairSt. Clair National Wildlife AreaUnknown
3
Lake St. ClairLake St. Clair and TributariesFair
2
Lake ErieLong Point Bay/Big CreekPoor
2
Lake ErieCanard RiverUnknown
3
Lake EriePoint Pelee National ParkExtirpated
3
Lake ErieRondeau BayExtirpated
3
Lake OntarioGananoque RiverExtirpated
3
Lake OntarioWellers Baytable notedUnknown
3
Lake OntarioWest LakeUnknown
2
Lake OntarioEast Laketable notedUnknown
3
Lake OntarioWaupoos Baytable notedUnknown
3
Lake OntarioSt. Lawrence RiverGood
2

(modified from Bouvier et al. 2010)

Lake Huron drainage

The first record of Pugnose Shiner from the Teeswater River, located in the Saugeen River watershed was in 2005 when three specimens were captured (S. D’Amelio, Trout Unlimited Canada, Guelph, ON, pers. comm. 2005). Pugnose Shiner was subsequently detected in 2009 and 2010 when two specimens were captured in a reservoir (Cargill Mill Pond) on the river and two were captured downstream of the reservoir (Marson et al. 2009). In 2010, 24 individuals were caught within the reservoir from 3 sampling sites (DFO unpublished data).

Pugnose Shiner was first collected from the Old Ausable Channel (OAC) in the early 1980s (ARRT 2006). Between 1982 – 2010, the Old Ausable Channel was sampled extensively, with a variety of gear types, by a variety of researchers relative to some other Canadian Pugnose Shiner populations. The population in the Old Ausable Channel is believed to have declined in recent years, as only 21 specimens were captured during a survey in 1997 compared to 110 in 1982, despite an increase in effort (Holm and Boehm 1998, ARRT 2006). In 2002, DFO sampled a 5 km reach of the Old Ausable Channel using various gear types and caught 43 Pugnose Shiner, only seven of which were caught in the 1 km reach sampled in 1982 and 1997, suggesting a further decline. However, DFO did not use a beach seine as was done by Holm and Boehm (1998), making inter-annual comparisons difficult. In 2004 and 2005, a total of 291 Pugnose Shiner was captured throughout the Old Ausable Channel (DFO, unpublished data).

L Lake, located near the Old Ausable Channel and containing similar habitat, was sampled in 2007 and 2010 by DFO but Pugnose Shiner was not captured, despite the fact that Lake Chubsucker (Erimyzon sucetta) (a species often found in association with Pugnose Shiner) and other black-lined shiners were detected. Further sampling at this location and other oxbow lakes near the Old Ausable Channel may detect the presence of the species.

Mouth Lake, located near the Old Ausable Channel and containing similar habitat, was sampled in 2010 by DFO at four sites and a total of 17 Pugnose Shiner were captured.

Lake St. Clair drainage

In Lake St. Clair, 222 Pugnose Shiner have been captured in Mitchell’s Bay as a result of sampling conducted in 1983, 1996, 2006 and 2007 (Holm and Mandrak 2002; ROM, Toronto, ON, unpublished data; DFO, unpublished data; K. Soper, Ontario Ministry of Natural Resources (OMNR), pers. comm., 2010). Sampling conducted in 1983 and 2006 yielded seven specimens from St. Luke’s Bay (ROM, Toronto, ON, unpublished data; DFO, unpublished data; Holm and Mandrak 2002). Additional sites in Lake St. Clair (31 sites) were sampled in 2007 by the Essex Region Conservation Authority; however, no Pugnose Shiner were captured (Nelson and Staton, draft).

The delta channels and freshwater coastal marshes of Walpole Island, located at the north end of Lake St. Clair, yielded 281 individuals during a survey in 1999 (Holm and Mandrak 2002) and three specimens were captured in 2002 (ROM, Toronto, ON, unpublished data).

The species was detected for the first time from the western diked marsh in the St. Clair unit of the St. Clair NWA during a graduate study in 2003 and was caught again in 2004 (Bouvier et al. 2010).

In 2003, DFO completed targeted, wadeable, surveys for fish species at risk in tributaries of Lake St. Clair and captured five Pugnose Shiner (two from Little Bear Creek and three from Whitebread Drain/Grape Run) (Mandrak et al. 2006b). In 2006, nine specimens were captured from Little Bear Creek (ROM, Toronto, ON, unpublished data) and in 2010, two specimens were captured (DFO, unpublished data).

Lake Erie drainage

In the westernmost part of its Canadian range, Pugnose Shiner is known from the Lake Erie drainage. The species was captured in Lake Erie from Point Pelee National Park in 1940 and 1941; from Rondeau Bay in 1940 and 1963; and, from Long Point Bay in 1947 and 1996 (Holm and Mandrak 2002). Despite surveys conducted between 1979 and 1996 at all three locations (with surveys dating back to 1946 in Point Pelee National Park), Pugnose Shiner were only collected in Long Point Bay.

Pugnose Shiner was first recorded from the Canard River, close to the confluence of the Detroit River, in 1994 when four specimens were captured (ROM, Toronto, ON, unpublished data).

The species was first recorded within Inner Long Point Bay in 1947, Turkey Point in 2007, and the tip of Long Point in 2007 (OMNR, unpublished data). Recent sampling within Inner Long Point Bay has added to our understanding of the species distribution within the bay. In 2004 DFO caught 29 specimens in Long Point Bay and one specimen in the Thoroughfare Point unit of Long Point NWA during a fish community survey (Marson et al. 2009). In 2007, 38 Pugnose Shiner were caught at eight sites in Turkey Point (Long Point Bay) (Nelson and Staton, draft). Sampling conducted by DFO in 2008 and 2009 yielded 24 specimens from Long Point Bay.

Sampling in 2008 and 2009 caught six specimens from Big Creek (Haldimand-Norfolk County), which is connected to Long Point Bay (DFO, unpublished data). The Big Creek specimens represent the first records of the species at this location. Sampling conducted by DFO in 2007 and 2008 yielded 15 specimens from Big Creek and Big Creek National Wildlife Area (Big Creek Unit only) (Haldimand-Norfolk County) (DFO, unpublished data). Sampling by Long Point Conservation Authority and OMNR in 2008 - 2010 has captured additional specimens.

Lake Ontario drainage

In Canada, Pugnose Shiner was first collected in the Gananoque River and the upper St. Lawrence River near the town of Gananoque in 1935 (Toner 1937, as cited in Holm and Mandrak 2002). It has not been collected in the Gananoque River since 1935 and it was last recorded from the St. Lawrence site in 1937 (Holm and Mandrak 2002); however, individuals were caught in 1989 at points east (Mallorytown Landing) and west (Eastview) of the original location (Holm and Mandrak 2002). In 2005, DFO captured 256 Pugnose Shiner from three sites adjacent to St. Lawrence Islands National Park, near the Grenadier Island Wetland Complex (Mandrak et al.2006a; J. Van Wieren, St. Lawrence Islands National Park, Mallorytown, ON, pers. comm., 2007). From 2006 to 2011, Parks Canada Agency (PCA) captured a total of 495 Pugnose Shiner at over 20 sites (both inside and outside of Park boundaries) from east of Mallorytown Landing to Wolfe Island near Kingston (OMNR 2006; J. Van Wieren, St. Lawrence Islands National Park, Mallorytown, ON, pers. comm., 2011).

Pugnose Shiner was detected for the first time in West Lake (Prince Edward County, eastern Lake Ontario) in 2009. Two specimens were collected during an electrofishing study conducted by DFO in June 2009 (DFO, unpublished data) and another 32 specimens were captured in September 2009 as a result of targeted sampling for the species (DFO, unpublished data). Subsequent targeted sampling around the lake in 2010 yielded an additional 70 Pugnose Shiner (DFO, unpublished data).

Pugnose Shiner was detected for the first time in Wellers Bay, East Lake and Waupoos Bay in 2010 as a result of targeted sampling by DFO (DFO, unpublished data). A total of 65 individual Pugnose Shiners were caught from 4 locations in Wellers Bay. A total of 112 individual Pugnose Shiners were caught from 11 locations from East Lake. A total of 172 individual Pugnose Shiners were caught from 4 locations from Waupoos Bay.

Percent of global abundance in Canada

Roughly 5 to 10% of the species’ global abundance probably occurs in Canada (ARRT 2006).

Population trend

The abundance of Pugnose Shiner has declined in Canada over the last 25 years, with an apparent decline in the Old Ausable Channel and likely losses at Point Pelee National Park, Rondeau Bay (ARRT 2006) and the Gananoque River. Although there are no data available for remaining extant sites, there is a reasonable expectation that similar declines may be occurring at these locations. There is no trend data available for the new locations.

1.4 Needs of the Pugnose Shiner

1.4.1 Habitat and biological needs

Spawn to embryonic (yolk-sac stage)

The northern extent of this species may be limited by its temperature requirements for spawning (21-29°C), which occurs in early to mid - June in Ontario (Holm and Mandrak 2002), but can be anywhere from mid - May into July over the distribution of this species. Spawning occurs in densely vegetated waters, no deeper than 2 m, with sand/silt and sometimes gravel substrates (Lane et al. 1996a). The Pugnose Shiner is a lithophil – a non-guarding, open substrate spawner – and eggs are broadcast over vegetation and substrate (Leslie and Timmins 2002). Submersed plants are required for successful reproduction, as they provide essential cover for the highly photophobic (sensitive to light) embryos (Leslie and Timmins 2002). Furthermore, Pugnose Shiner was observed to only move into shallow depths once beds of submergent vegetation appeared at or near the time of spawning (Becker 1983). Becker (1983) also described evidence of ‘prespawning schools’ - large schools of individuals (500+), much larger than the normal school size of 15-35 - that aggregate prior to spawning events.

Young-of-the-Year (YOY)

YOY Pugnose Shiner require shallow (< 2 m), heavily vegetated habitats, with substrates of sand and silt (Lane et al.1996b). Juvenile Pugnose Shiner in Ontario have been associated with stonewort (Chara vulgaris), Eurasian watermilfoil (Myriophyllum spicatum), wild celery (Vallisneria americana), pondweeds (Potamogeton spp.) and naiad (Najas flexilis) (Leslie and Timmins 2002).

Adult

Adult Pugnose Shiner are typically found in slow-moving, clear waters of streams, large lakes and embayments with low gradients and abundant rooted vegetation (Carlson 1997; ARRT 2006). Records of Pugnose Shiner have also been obtained from sheltered inshore ponds, diked wetlands, stagnant channels and protected bays adjacent to large waterbodies (Parker et al. 1987; DFO, unpublished data). Substrates that are associated with adults of this species include sand, mud, organic detritus, clay and marl (Parker et al. 1985; NatureServe 2009). Both emergent and submergent aquatic plants characterize the areas where Pugnose Shiner is typically found, especially stonewort (Becker 1983). Other types of aquatic vegetation that the adults of this species are often associated with include filamentous algae (especially Spirogyra spp.), wild celery, naiad, pondweed and waterweed (Elodea spp.), as well as emergent plants such as cattail (Typha spp.), bulrush (Scirpus spp.) and sedge (Carex spp.) (Becker 1983; Holm and Mandrak 2002; Leslie and Timmins 2002). Additionally, adult Pugnose Shiner are often associated with Eurasian watermilfoil, an exotic plant species. However, Eurasian watermilfoil in high densities may have negative impacts on the species. For example, a proliferation of Eurasian watermilfoil was linked to the extirpation of the Pugnose Shiner and seven other minnow species in a Wisconsin lake (Lyons 1989). Recent habitat analysis from data from the St. Lawrence Islands National Park found a correlation between the presence of greater than 83% submergent vegetation and Pugnose Shiner presence. Additionally, the presence of Potamageton species (particularly Sago Pondweed) appears to be important (J. Van Wieren, unpublished data).

Pugnose Shiner is typically collected at shallow depths in less than 3 m of water (Holm and Mandrak 2002), but such sampling often occurs in warmer months and this species is believed to move to deeper waters in cool months (Becker 1983). Although it has been suggested that Pugnose Shiner prefers areas with low turbidity (Trautman 1981; Scott and Crossman 1998; Holm and Mandrak 2002), specimens have been captured in areas with higher turbidity levels (e.g., Secchi depths of 0.3 m in Rondeau Bay) (Parker et al. 1987). The species has occasionally been collected from shallow, turbid, waters devoid of aquatic vegetation (Leslie and Timmins 2002).

Pugnose Shiner has been described as a detritivore (feeds on decomposing organic matter) that scrapes accumulated detritus from plant leaves (Goldstein and Simon 1999). However, other accounts suggest the species could be an omnivore. For example, Smith (1985) states that the diet is predominantly made up of various plants and animals up to 2 mm in size, especially stonewort and filamentous green algae, cladocerans, small leeches, and caddisfly larvae (Holm and Mandrak 2002). However, Becker (1983) did not find food items to be limited by this species’ small gape. The stomach contents of eight specimens caught in Mitchell’s Bay (Lake St. Clair) consisted primarily of cladocerans (Chydorus sphaericusand Bosmina longirostris); one individual contained an estimated 1210 C. sphaericus and 370 B. longirostris (Holm and Mandrak 2002). In aquaria, Pugnose Shiner preferentially grazed on plant material, a fact reinforced by its elongated intestine, and only switched to animal sources after the plant source was exhausted (Becker 1983).

1.4.2 Ecological role

Although there are scant data on the physiology, behaviour and ecology of this species (Leslie and Timmins 2002), it is frequently noted that the Pugnose Shiner is generally sensitive to habitat change, and its continued presence is indicative of good environmental conditions (Smith 1985; Carlson 1997; Essex-Erie recovery strategy (EERT) 2008). Additionally, the Pugnose Shiner is considered by some to be the most sensitive of the black-lined shiner group (Fago 1992, as cited in Carlson 1997). The presence of Blackchin Shiner has been shown to be a good indicator of the presence of the more secretive and timid Pugnose Shiner (Carlson 1997). The Pugnose Shiner is known to be a prey item for a number of piscivorous fishes (Nelson 2006).

1.4.3 Limiting factors

Limiting factors for Pugnose Shiner are not known with certainty; however, available information suggests that they are limited to quiet, clear, densely vegetated waters (ARRT 2006). Even as early as the late 1950s, researchers were indicating that localized populations of this species had been reduced or extirpated due to turbidity and the removal of aquatic vegetation (Bailey 1959; Trautman 1981; Scott and Crossman 1998). Its close association with wetlands may limit the recovery of this species due to the loss of suitable habitat across its range (ARRT 2006).

1.5 Threats

1.5.1 Threat classification

Bouvier et al. (2010) assessed threats to Pugnose Shiner populations in Canada (Table 3). Known and suspected threats were ranked with respect to threat likelihood and threat impact for each population. The threat likelihood and threat impact were then combined to produce an overall threat status. A certainty level was also assigned to the overall threat status, which reflected the lowest level of certainty associated with either threat likelihood or threat impact. See Bouvier et al. (2010) for further details. Additional information is provided in the subsequent threat summaries.

Table 3. Summary of threats to Pugnose Shiner populations in Canada
Threat status and certainty (), by population, for Pugnose Shiner in Ontario. Certainty: 1= causative studies; 2=correlative studies; and 3=expert opinion. (Table revised from Bouvier et al. (2010))
ThreatsLake Erie drainage
Long Point Bay/Big Creek
Lake Erie drainage
Canard River
Lake Erie drainage
Point Pelee National Park
Lake Erie drainage
Rondeau Bay
Lake Huron drainage
Old Ausable Channel
Lake Huron drainage
Teeswater River
Habitat modificationsHigh
(3)
High
(3)
Medium
(3)
High
(3)
High
(3)
Unknown
(3)
Aquatic vegetation removalMedium
(3)
Medium
(3)
Medium
(3)
High
(3)
Medium
(3)
Unknown
(3)
Sediment loading/turbidityHigh
(3)
High
(3)
Medium
(3)
High
(3)
High
(3)
Unknown
(3)
Nutrient loadingHigh
(3)
High
(3)
Medium
(3)
High
(3)
High
(3)
Unknown
(3)
Exotic speciesMedium
(3)
Medium
(3)
Medium
(3)
Medium
(3)
Medium
(3)
Unknown
(3)
Baitfish industryLow
(3)
Low
(3)
Low
(3)
Low
(3)
Low
(3)
Low
(3)
Changes in
trophic dynamics
Unknown
(3)
Unknown
(3)
Low
(3)
Low
(3)
Low
(3)
Unknown
(3)

 

Table 3 (continued). Summary of threats to Pugnose Shiner populations in Canada
Threat status and certainty (), by population, for Pugnose Shiner in Ontario. Certainty: 1= causative studies; 2=correlative studies; and 3=expert opinion. (Table revised from Bouvier et al. (2010))
ThreatsLake St. Clair drainage
Lake St. Clair and Tributaries
Lake St. Clair drainage
St. ClairTablenotee NWA
Lake Ontario drainage
St. Lawrence River
Lake Ontario drainage
Gananoque River
Lake Ontario drainage
West Lake
Lake Huron drainageTable notef
Mouth Lake
Lake Ontario drainageTable notef
Wellers Bay
Lake Ontario drainageTable notef
Waupoos Bay
Lake Ontario drainageTable notef
EastLake
Habitat modificationsHigh
(3)
Medium
(3)
Medium
(3)
Unknown
(3)
Medium
(3)
Medium
(3)
High
(3)
High
(3)
Medium
(3)
Aquatic vegetation
removal
Medium
(3)
Low
(3)
Medium
(3)
Unknown
(3)
Medium
(3)
Medium
(3)
Medium
(3)
Medium
(3)
Medium
(3)
Sediment loading/turbidityHigh
(3)
Low
(3)
High
(3)
Unknown
(3)
High
(3)
Medium
(3)
Medium
(3)
Medium
(3)
High
(3)
Nutrient loadingHigh
(3)
Medium
(3)
High
(3)
Unknown
(3)
High
(3)
High
(3)
High
(3)
High
(3)
High
(3)
Exotic speciesMedium
(3)
Medium
(3)
Medium
(3)
Unknown
(3)
Medium
(3)
Unknown
(3)
Medium
(3)
Medium
(3)
Medium
(3)
Baitfish industryLow
(3)
 Low
(3)
Low
(3)
Low
(3)
Low
(3)
Low
(3)
Low
(3)
Low
(3)
Changes in
trophic dynamics
Unknown
(3)
Unknown
(3)
Unknown
(3)
Unknown
(3)
Unknown
(3)
Unknown
(3)
Unknown
(3)
Unknown
(3)
Unknown
(3)

1.5.2 Description of threats

Habitat modifications

The preferred habitat of Pugnose Shiner has become isolated as a result of habitat loss and/or degradation across its range. This has been suggested by Leslie and Timmins (2002) to prevent connectivity of fragmented populations and may prevent gene flow between existing populations and/or inhibit colonization of other suitable habitats. Habitat loss can occur in the form of lake and river shoreline modifications (e.g., shoreline hardening projects, piers, docks, marinas) (Holm and Mandrak 2002). Parker et al. (1987) suggested that the amount of available habitat for Pugnose Shiner may have been diminished in quality and quantity due to a general decline in water quality and an increase in lakeshore development. The loss of wetland and riparian forest habitats across southern Ontario has been dramatic since the late 1800s. Continued development of wetlands is a concern. Currently, the general regions where Pugnose Shiner is known to exist have experienced changes in habitat due to development. For example, the Grenadier Island Wetland Complex (Thousand Islands region in the St. Lawrence River), which currently supports a large population of Pugnose Shiner, is threatened by proposed development projects, including three large subdivisions as well as cottage development proposals (J. Van Wieren, St. Lawrence Islands National Park, Mallorytown, ON, pers. comm., 2007). Some fishermen and resource users from Walpole Island First Nation have noted a decrease in aquatic vegetation which they attribute to scouring from wakes from ships and lower water levels (C. Jacobs, Walpole Island First Nation, pers. comm., 2011).

Aquatic vegetation removal/control

The removal of aquatic plants from the shallow littoral areas of lakes and rivers is believed to be a serious threat to Pugnose Shiner, given that it is a timid, species that requires aquatic plants for cover as well as a source of food, spawning and larval habitat (Eddy and Underhill 1974, Mandrak and Holm 2002). Pugnose Shiner larvae are highly photophobic when first hatched and require vegetation for cover (Leslie and Timmins 2002). The physical act of removing aquatic vegetation would be harmful to the species; the mechanical removal of vegetation disturbs sediments and creates turbid conditions, and vegetation removal using herbicides introduces potentially harmful chemicals into the water.

Sediment loading/turbidity

Pugnose Shiner is believed to be sensitive to turbidity (Bailey 1959; Carlson 1997; Scott and Crossman 1998; ARRT 2006). As such, excessive sediment inputs constitute a serious threat to the species. Bailey (1959) described that increased agricultural use of land and water as reducing the clarity in typical Pugnose Shiner habitats. Sediment loadings could affect Pugnose Shiner by impacting the species’ respiration rates and vision, as well as altering preferred habitat through decreased water clarity, increased siltation of substrates, and the possible selective transport of pollutants, including phosphorus. The excessive siltation of substrates could negatively affect Pugnose Shiner by smothering eggs deposited in the substrate or by degrading potential spawning habitat.

Nutrient loading

Excess nutrient (nitrates and phosphorus) inputs into waterbodies can negatively influence Pugnose Shiner habitat through the development of algal blooms and associated reduced dissolved oxygen concentrations when these blooms die off. Nutrient loading is listed as a primary threat in some areas currently and historically occupied by Pugnose Shiner (i.e., Long Point Bay, Point Pelee National Park, Rondeau Bay) (EERT 2008). This is particularly evident in Rondeau Bay where nutrient loading from adjacent agriculture and residential areas is negatively impacting wetland habitats. Vegetation diversity tends to decline with increased nutrients as species such as cattail and common reed grass (Phragmites australis) are superior competitors for the excess nutrients (Gilbert et al. 2007). Although wetlands are highly valued for their water filtering capacity, these systems are negatively impacted when nutrient (and chemical) concentrations far exceed background levels (Gilbert et al. 2007).

The persistent elevated concentrations of total phosphorus and apparent trend of increasing nitrate ion concentrations in some watercourses suggest that this is an ongoing concern (EERT, 2008).

Exotic species

Common Carp (Cyprinus carpio) may potentially harm Pugnose Shiner by uprooting essential aquatic vegetation required for spawning and cover. Common Carp could also cause an increase in turbidity levels as a result of bioturbation (disturbance of sediments through feeding and other activities) (Lougheed et al. 2004); this would be unlikely in areas with sandy substrates (ARRT 2006), but it may pose a risk in Pugnose Shiner locations with finer substrates where Common Carp occur.

Exotic plant species are also a potential concern for Pugnose Shiner in that they can significantly alter wetland vegetation communities (EERT2008). Two species of particular concern include common reed grass and Eurasian watermilfoil. Eurasian watermilfoil is an aggressive submerged aquatic plant native to Europe that grows quickly in spring and produces dense mats of vegetation (Environment Canada 2006). This robust plant is able to out-compete established native plant species and create a monoculture, removing the preferred plants of the Pugnose Shiner. In the 1960s, an explosion of Eurasian watermilfoil replaced abundant beds of submerged plants at Rondeau Bay. Then the watermilfoil mysteriously died out in 1977, and left the habitat unsuitable for re-colonization by any submerged aquatics. It was thought that this was due to increased wave effect that caused erosion and prevented settling of the sediment load entering the bay (Hanna 1984). Also, the extirpation of Pugnose Shiner, as well as seven other species, in one lake in Wisconsin, was linked to the proliferation of Eurasian watermilfoil (Lyons 1989). The thick canopies of vegetation can contribute extra phosphorus and nitrogen to the water column, which can increase algal production which can decrease dissolved oxygen. Unfortunately, the removal of Eurasian watermilfoil may also be detrimental to Pugnose Shiner, as the preferred methods of removal include use of the herbicide 2,4-D or mechanical harvesting, which may compromise remaining native plants, particularly in Rondeau Bay (EERT 2008).

Incidental harvest (baitfishing)

Fishery activities that indirectly harvest Pugnose Shiner have the potential to negatively impact population abundance. Of concern is the incidental by-catch of the species in commercial baitfish operations. Pugnose Shiner is not a legal baitfish in Ontario (Cudmore and Mandrak 2011; OMNR 2011) and the extent to which the species is a by-catch of baitfish harvesting in Ontario is unknown. Due to the species relative rarity and sparse distribution, the probability of it being captured incidentally are likely to be low; however, by-catch is still of concern and should be considered a potential threat.

Changes in trophic dynamics

Apparent shifts in fish communities from a cyprinid-dominated (minnows) assemblage to one dominated by centrarchids (sunfishes), have been suggested to have negative impacts on Pugnose Shiner (Holm and Boehm 1998), particularly in the Old Ausable Channel (ARRT 2006). Results of these shifts could include an increase in the number and diversity of predators present and/or an increase in interspecific competition for resources (Holm and Mandrak 2002). Evidence suggests that minnow diversity and abundance decreases with an increase in the number and diversity of littoral predators such as basses (Micropterus spp.) and pikes (Esox spp.) (Whittier et al. 1997). Species such as Grass Pickerel (Esox americanus vermiculatus) and Northern Pike (E. lucius), co-existed with Pugnose Shiner at Point Pelee National Park in the 1940s; however, other potential predators, such as Black Crappie (Pomoxis nigromaculatus), Largemouth Bass (Micropterus salmoides), and Warmouth (Lepomis gulosus), were not recorded in the Park until 1958 (Holm and Mandrak 2002). It is possible that this increase in predators may have negatively impacted Pugnose Shiner. However, the species was found in association with a wide range of potential predators at sites near Walpole Island in 1999, where it is relatively common (Holm and Mandrak 2002). Potential predators were frequently abundant and included Black Crappie, Bowfin (Amia calva), bullheads (Ameiurus spp.), Grass Pickerel, Largemouth Bass, Longnose Gar (Lepisosteus osseus), Northern Pike, Rock Bass (Ambloplites rupestris), and Yellow Perch (Perca flavescens) (Holm and Mandrak 2002).

It has been theorized that increased competition for resources with juveniles of species such as Black Crappie, Bluegill (Lepomis macrochirus) and adult Brook Silverside ((Labidesthes sicculus), none of which were collected until 1958) may have also played a role in the decline of Pugnose Shiner at Point Pelee National Park. These species have a diet similar to Pugnose Shiner, feeding heavily on cladocerans and occasionally on plant material (Holm and Mandrak 2002). However, Brook Silverside as well as juvenile Bluegill and Black Crappie, occurred together with Pugnose Shiner in 1999 collections at Walpole Island (Holm and Mandrak 2002), so it is uncertain to what extent competition for food is a threat.

Climate change

Climate change has the potential to have significant effects on aquatic communities of the Great Lakes basin through several mechanisms. These include increases in water and air temperatures; changes (decreases) in water levels; shortening of the duration of ice cover; increases in the frequency of extreme weather events; emergence of diseases; and, shifts in predator-prey dynamics (Lemmen and Warren 2004). This may be particularly relevant for the Pugnose Shiner due to its use of coastal wetlands and nearshore habitats. However, it is not possible to predict the likelihood and impact of climate change on each population. Therefore, climate change was not included in the population-specific threat analysis.

1.6 Actions already completed or underway

Ecosystem-based recovery strategies

The following aquatic ecosystem-based recovery strategies include Pugnose Shiner and are currently being implemented by their respective recovery teams. Each recovery team is co-chaired by DFO and a Conservation Authority and receives support from a diverse partnership of agencies and individuals. Recovery activities implemented by these teams include active stewardship and outreach/awareness programs to reduce identified threats; for further details on specific actions currently underway, see Section 2.5.1 Recovery planning (stewardship, outreach, and awareness). Funding for these actions is supported by Ontario’s Species at Risk Stewardship Fund and the Government of Canada’s Habitat Stewardship Program (HSP) for species at risk. Additionally, research requirements for species at risk identified in recovery strategies are funded, in part, by the federal Interdepartmental Recovery Fund (IRF). Note: Although these Recovery Strategies are supported by DFO, they are not formally endorsed as recovery strategies under SARA.

Ausable River ecosystem recovery strategy (ARRT)

The ARRT has developed an ecosystem-based recovery strategy for the 16 aquatic species assessed as at risk by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) in the Ausable River basin. This plan covers six aquatic species at risk listed under SARA, including Pugnose Shiner. The goal of the strategy is to “prepare a recovery plan (recovery strategy and action plan) that sustains and enhances the native aquatic communities of the Ausable River through an ecosystem approach that focuses on species at risk” (ARRT 2006).

Essex-Erie recovery strategy (EERT)

The ecosystem approach has also been taken in the Essex-Erie recovery strategy, which covers 14 aquatic species assessed by COSEWIC as being at risk, including Pugnose Shiner (EERT 2008). The Essex-Erie region is located on the north shore of Lake Erie, bordered to the east by the Grand River watershed, to the west by the Detroit River and to the north by Lake St. Clair and the Thames River watershed. The long-term goal of this strategy is “to maintain and restore ecosystem quality and function in the Essex-Erie region to support viable populations of fish species at risk, across their current and former range” (EERT 2008).

Walpole Island ecosystem recovery strategy

The Walpole Island Ecosystem recovery team was established in 2001 to develop an ecosystem-based recovery strategy for the area containing the St. Clair delta, the largest freshwater delta in the Great Lakes, with the goal of outlining steps to be taken to maintain or rehabilitate the ecosystem and species at risk (Bowles 2005). This recovery strategy covers several aquatic species listed under SARA, including Pugnose Shiner. The recovery goal of the Walpole Island Ecosystem recovery strategy is “to conserve and recover the ecosystems of the Walpole Island Territory in a way that is compliant with the Walpole Island First Nation Environmental Philosophy Statement, provides opportunities for cultural and economic development and provides protection and recovery for Canada’s species at risk” (Bowles 2005).

Recent surveys

Table 4 summarizes recent fish surveys conducted by various agencies within areas of known Pugnose Shiner occurrence.

Table 4. Summary of recent (since 2000) fish assemblage surveys in areas of known Pugnose Shiner occurrence. Please note this is not a comprehensive list.
Waterbody/general areaSurvey description (years of survey effort)Gear TypePugnose Shiner detected (Yes/No)
Old Ausable Channel/Mouth LakeTargeted sampling for species at risk, DFO, Ausable Bayfield Conservation Authority (ABCA )(2002, 2004, 2005, 2009, 2010)seine; boat electrofishing unit; fyke nets
Yes
Teeswater RiverTargeted sampling, DFO (2005, 2009, 2010)seine; backpack electrofishing unit
Yes
Lake St. Clair and TributariesNearshore fish community survey, OMNR (2007, 2008)seine; boat electrofishing unit
Yes
Lake St. Clair and TributariesIndex Surveys of Lake St. Clair, OMNR (annually) 
No
Lake St. Clair and TributariesFish community survey, Michigan DNR (1996-2001)trawl
Yes
Lake St. Clair and TributariesFish community survey at Walpole Island, ROM (1999 - 2002)seine; boat electrofishing unit
No
Lake St. Clair and TributariesEssex-Erie targeted sampling for fishes at risk, DFO (2007)seine; fyke nets
No
Lake St. Clair and TributariesYoung-of-the-Year index seine survey, OMNR (intermittently since 1979)seine
No
Lake St. Clair and TributariesFall trap net survey, OMNR (1974-2007, excluding 1999 and 2002, annual)trap nets
Yes
Lake St. Clair and TributariesTargeted sampling for species at risk in Lake St. Clair watershed, DFO (2003, 2005-2010)seine; backpack electrofishing unit
No
Lake St. Clair and TributariesNearshore fish community survey, DFO (2010)trawl
No
Detroit RiverFish-habitat associations of the Detroit River, DFO and the University of Windsor (2003-2004)seine; boat electrofishing unit
No
Detroit RiverCoastal wetlands of Detroit River, DFO and the University of Guelph (2004-2005)boat electrofishing unit; fyke nets
No
Detroit RiverFish community surveys, DFO and OMNR (2003-2004)boat electrofishing unit;
No
Essex regionInland watercourses (2000-2001), targeted sampling (2004), surveys of drains and inland watercourses (2004, 2007), DFO and Essex Region Conservation Authority (ERCA)backpack electrofishing unit
Yes
Point Pelee National Park (PPNP) and Nearshore HabitatsFish species composition study (Surette 2006), University of Guelph, DFO and PPNP (2002-2003)seine; trap nets; fyke nets; minnow trap; Windermere trap
No
Point Pelee National Park (PPNP) and Nearshore HabitatsSpotted Gar (Lepisosteus oculatus) research, University of Windsor, DFO (2007-2009)boat electrofishing unit; fyke nets
No
Rondeau BayFish community surveys, OMNR and DFO (2004-2005)seine; boat electrofishing unit; fyke nets
No
Rondeau BaySpotted Gar research, University of Windsor, DFO (2007-2009)boat electrofishing unit; fyke nets
No
Long Point BayIndex Surveys of Long Point Bay, OMNR (annually)trawl
Yes
Long Point BayFish community assessment, OMNR (2007-2009)seine; boat electrofishing unit; fyke nets
Yes
Long Point BayEssex-Erie targeted sampling for species at risk (SAR) (Turkey Point), ERCA/DFO (2007)seine; boat electrofishing unit; trap nets
Yes
Long Point BayLong Point Bay Conservation Authority targeted sampling for SAR in Long Point Bay, LPBCA (2009, 2010)seine; fyke nets
Yes
Wellers Bay, West Lake, East Lake, Waupoos BayFish community assessment, DFO (2009)seine; backpack electrofishing unit
Yes
Wellers Bay, West Lake, East Lake, Waupoos BayTargeted sampling DFO (2009, 2010)seine; backpack electrofishing unit
Yes
Wellers Bay, West Lake, East Lake, Waupoos BaySpotted gar targeted sampling (2009) 
No
St. Lawrence RiverFish assemblage surveys, DFO/St. Lawrence Islands National Park (2005)seine; boat electrofishing unit; fyke nets; minnow trap
Yes
St. Lawrence RiverNear shore fish community long-term monitoring program, Parks Canada (2006-2011)seine; boat electrofishing unit; fyke nets; minnow trap
Yes
St. Lawrence RiverFish assemblage survey, DFO (2004)boat electrofishing unit
No
St. Lawrence RiverTargeted sampling, DFO (2009, 2010)seine
Yes
St. Lawrence RiverFish community survey, MNR (annually)gill nets
No

1.7 Knowledge gaps

There are numerous aspects regarding the biology and ecology of the Pugnose Shiner that remain unknown. This information is required to refine recovery approaches and to aid in identifying critical habitat identification. Threat clarification is required to determine the exact nature and extent of threats facing Pugnose Shiner. For example, the species has been recorded in regions affected by a suite of chemicals exceeding provincial and/or federal guidelines and the specific indirect/direct effects of these chemicals and their interactions with other stressors on Pugnose Shiner are not known (EERT 2008). Another source of uncertainty is the effect that the loss and deterioration of coastal and inland wetlands will have on the distribution of Pugnose Shiner and its abilities to move between and colonize new areas (Leslie and Timmins 2002; EERT 2008). The impacts of exotic fishes (e.g., Common Carp, Round Goby (Neogobius melanostomus)) on Pugnose Shiner and its habitat are unknown and require assessment.

Introduction