Salish Sucker (Catostomus sp. cf. catostomus): recovery strategy, 2020

Official title: Recovery Strategy for the Salish Sucker (Catostomus sp. cf. catostomus) in Canada, 2020

Species at Risk Act
Recovery strategy series

Original publication: 2016
1^st amendment: 2020
(changes made to all sections)

Previous versions of this recovery strategy can be found on the Species at Risk Public Registry

Preface

The federal, provincial, and territorial government signatories under the Accord for the Protection of Species at Risk (1996) agreed to establish complementary legislation and programs that provide for effective protection of species at risk throughout Canada. Under the Species at Risk Act (S.C. 2002, c.29) (SARA), the federal competent ministers are responsible for the preparation of a recovery strategy for species listed as extirpated, endangered, or threatened and are required to report on progress five years after the publication of the final document on the Species at Risk Public Registry.

The Minister of Fisheries and Oceans is the competent minister under SARA for the Salish Sucker and has prepared this recovery strategy, as per section 37 of SARA. A recovery strategy was completed for Salish Sucker and posted on the Species at Risk Registry in 2016 (DFO 2016). This 2020 recovery strategy is the first amendment to the 2016 recovery strategy. It updates biology, the recovery feasibility assessment, threats, population and distribution objectives, and areas identified as critical habitat.

In preparing this recovery strategy, the competent minister has considered, as per section 38 of SARA, the commitment of the Government of Canada to conserving biological diversity and to the principle that, if there are threats of serious or irreversible damage to the listed species, cost-effective measures to prevent the reduction or loss of the species should not be postponed for a lack of full scientific certainty. To the extent possible, this recovery strategy has been prepared in cooperation with the Province of British Columbia as per section 39(1) of SARA.

As stated in the preamble to SARA, success in the recovery of this species depends on the commitment and cooperation of many different constituencies that will be involved in implementing the directions set out in this strategy and will not be achieved by Fisheries and Oceans Canada, or any other jurisdiction alone. The cost of conserving species at risk is shared amongst different constituencies. All Canadians are invited to join in supporting and implementing this strategy for the benefit of the Salish Sucker and Canadian society as a whole.

The Action Plan for the Nooksack Dace (Rhinichthys cataractae) and the Salish Sucker (Catostomus sp.) in Canada (DFO 2017) provides information on recovery measures to be taken by Fisheries and Oceans Canada and other jurisdictions and/or organizations involved in the conservation of the species. Implementation of this recovery strategy is subject to appropriations, priorities, and budgetary constraints of the participating jurisdictions and organizations.

Acknowledgments

Fisheries and Oceans Canada (DFO) developed this amended 2020 recovery strategy for Salish Sucker. DFO acknowledges the efforts of Mike Pearson (Pearson Ecological), who made the updates to the document with contributions from Erin Gertzen, Sean MacConnachie and Martin Nantel (DFO).

DFO extends their appreciation to the authors of the 2016 recovery strategy including Tom G. Brown (DFO), Karen Calla (DFO), Todd Hatfield (Ecofish Research), Don McPhail (University of British Columbia (UBC)), Mike Pearson, John Richardson (UBC), Jordan Rosenfeld (B.C. Ministry of Environment (B.C. MOE)), Dan Sneep (DFO), Dolph Schluter (UBC), Heather Stalberg (DFO), Marina Stjepovic (Township of Langley), Eric Taylor (UBC), and Paul Wood (UBC).

Executive summary

The Salish Sucker (Catostomus sp. cf. catostomus) was listed as Endangered under the Species at Risk Act (SARA) in 2005, and was re-classified as Threatened under SARA in 2019. This recovery strategy is considered one in a series of documents for this species that are linked and should be taken into consideration together, including the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) Status Report (COSEWIC 2012), the Science Advisory Report from the recovery potential assessment (RPA) (DFO 2015), and the joint Nooksack Dace (Rhinichthys cataractae ssp.) and Salish Sucker action plan (DFO 2017). Recovery has been determined to be biologically and technically feasible.

A recovery strategy was completed for Salish Sucker and posted on the Species at Risk Public Registry in 2016 (DFO 2016). This 2020 recovery strategy is the first amendment to the 2016 recovery strategy. It updates the biology, recovery feasibility assessment, threats, population and distribution objectives, and areas identified as critical habitat.

The Salish Sucker is a small-bodied, fine-scaled fish documented in 11 watersheds in the Fraser Valley, British Columbia (B.C.). It is a genetically and physically unique form of the widespread and common Longnose Sucker (C. catostomus) that evolved in geographic isolation in Washington State during glaciation (McPhail 2007). Salish Sucker populations have been in decline since at least the 1960s in Canada.Adults are most abundant in headwater marshes and ponds. Juveniles are generally found in shallow pools and glides containing cover. Spawning occurs in riffle habitats over fine gravel. Most individuals have small home ranges, although some individuals move kilometres during the spawning period. Within watersheds, distribution is concentrated in small areas, with a few sites harbouring most of the population.

The main threats facing the species are described in section 5 and include: hypoxia, seasonal lack of water, harmful substances, sediment deposition, habitat fragmentation, physical destruction of habitat and increased predation from aquatic invasive species.

The population and distribution objectives (section 6) for the Salish Sucker are:

• population objective:
  • long-term: reach or exceed watershed-specific population objectives described in section 6 by 2035
• distribution objectives:
  • short-term: continued presence in all eleven currently occupied watersheds
  • long-term: presence in all critical habitat reaches by 2035

A description of the broad strategies to be taken to address threats to the species’ survival and recovery, as well as research and management approaches needed to meet the population and distribution objectives are included in section 7. These informed the development of specific recovery measures in the Action Plan for the Nooksack Dace (Rhinichthys cataractae) and the Salish Sucker (Catostomus sp.) in Canada (DFO 2017).

For the Salish Sucker, critical habitat is identified to the extent possible, using the best available information, and provides the functions and features necessary to support the species’ life‑cycle processes and to achieve the species’ population and distribution objectives. section 8 of this recovery strategy identifies critical habitat for Salish Sucker as those reaches in the eleven occupied watersheds that have more than 50 m in length of continuous pool habitat with a water depth exceeding 70 cm at summer low flows. Critical habitat within those identified reaches includes all the aquatic habitats, including features and attributes identified in section 8, and all riparian areas on both banks for the entire length of the identified aquatic reaches. Riparian critical habitat is continuous and extends laterally (inland) from the top of bank to a width equal to the widest zone of sensitivity calculated for five riparian features and functions. The total length of aquatic critical habitat identified for Salish Sucker in this recovery strategy is 196.5 km (of 384.2 km of surveyed stream channel) and the area of riparian critical habitat associated with the aquatic critical habitat reaches is 818.1 hectares.

A SARA Critical Habitat Order is currently in place to legally protect from destruction Salish Sucker critical habitat identified in the 2016 recovery strategy (DFO 2016). This amended recovery strategy includes updates to critical habitat identification.

Recovery feasibility summary

The purposes of the Species at Risk Act (SARA) are to prevent wildlife species from being extirpated or becoming extinct, to provide for the recovery of wildlife species that are extirpated, endangered or threatened as a result of human activity and to manage species of special concern to prevent them from becoming endangered or threatened.

Using criteria outlined in table 1 below, DFO determined that the recovery of Salish Sucker is feasible based on species characteristics and thresholds required to approach the historical condition^{Footnote 1} of the species. While uncertainty^{Footnote 2} remains, Salish Sucker’s recovery can feasibly be achieved with habitat improvements.

Table 1a: Recovery feasibility evaluation for Salish Sucker; survival threshold.

1 Introduction

The Salish Sucker (Catostomus sp. cf. catostomus) was listed as Endangered under the Species at Risk Act (SARA) in 2005, and was re-classified as Threatened under SARA in 2019.

This recovery strategy is part of a series of documents regarding Salish Sucker that should be taken into consideration together, including the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) Status Report (COSEWIC 2012 [PDF - 1.55 MB]), the Science Advisory Report from the recovery potential assessment (RPA) (DFO 2015), and the joint Nooksack Dace and Salish Sucker action plan (DFO 2017). The COSEWIC Status Report contains basic biological information on the species and an assessment classifying the species as data deficient, not at risk, extinct, extirpated, endangered, threatened or special concern. The RPA is a research document undertaken by DFO Science to provide the information and scientific advice required to implement SARA and inform the recovery strategy, relying on the best available scientific information, data analyses and modeling, and expert opinions. A recovery strategy is a planning document that identifies what needs to be done to arrest or reverse the decline of a species. It sets objectives and identifies the main areas of activities to be undertaken. An action plan contains detailed planning aimed to help recover the species.

2 Committee on the Status of Endangered Wildlife in Canada species assessment information

Assessment summary: November 2012

Common name: Salish Sucker

Scientific name: Catostomus sp. cf. catostomus

COSEWIC status: Threatened

Reason for designation: This small fish has a restricted and fragmented range in southwestern British Columbia where it is susceptible to a continuing decline in habitat quality. An improvement in status from Endangered stems from a small increase in the number of known locations (from 9 to 14), including one location thought to have been extirpated, and some improvements in quality of habitat in areas subject to restoration.

Canadian occurrence: British Columbia

Status history: Designated Endangered in April 1986. Status re-examined and confirmed in November 2002. Status re-examined and designated Threatened in November 2012.

3 Species status information

The conservation status of the Salish Sucker within relevant jurisdictions is summarized in table 2. Based on available information, Canada contains approximately 9.3 percent of the global range (COSEWIC 2012).

^a G = Global Status; N = National Status; S = Subnational Status; 1= Critically Imperiled

^b Salish Sucker was listed as Endangered under SARA in 2005, and was re-classified as Threatened under SARA in 2019

Upon listing as a Threatened or Endangered species under Schedule 1 of SARA, a species becomes protected wherever it is found by section 32 of SARA:

 “No person shall kill, harm, harass, capture or take an individual of a wildlife species that is listed as an extirpated species, an endangered species or a threatened species.” [s. 32(1)]

“No person shall possess, collect, buy, sell or trade an individual of a wildlife species that is listed as an extirpated species, an endangered species or a threatened species, or any part or derivative of such an individual.” [s. 32(2)]

Under section 73 of SARA, the competent minister may enter into an agreement or issue a permit authorizing a person to engage in an activity affecting a listed wildlife species, any part of its critical habitat or its residences.

4 Species information

4.1 Description

The Salish Sucker (Catostomus sp. cf. catostomus) is a genetically and physically unique form of the Longnose Sucker (C. catostomus), a widespread fish species in North America (COSEWIC 2012). Salish Sucker arose when a Longnose Sucker population was geographically isolated in the Chehalis River valley (present-day Washington State) during the Pleistocene glaciations (McPhail 2007). The Salish Sucker is considered an evolutionarily significant unit (McPhail and Taylor 1999) and can be considered a “species in the making” (McPhail 1987). Within Canada, the Salish Sucker is present in 11 streams, wetlands and sloughs of the Fraser Valley between Surrey and Chilliwack in southern B.C. A number of populations may contain less than 100 breeding adults, while others number in the low thousands (DFO 2015).

Body colouration is dark-green and mottled with black on the back and whitish on the belly. A broad red stripe develops on the sides during the spring spawning season, especially in males. Scales are fine, the snout is short and blunt, and the small mouth is located on the lower surface of the head (McPhail and Carveth 1994). Few males exceed 200 mm in length and they can reach sexual maturity at less than 100 mm; females seldom exceed 250 mm (Pearson and Healey 2003).

4.2 Population abundance and distribution

Populations of Salish Sucker have been documented in 11 watersheds in the Fraser Valley, B.C. (table 3; figure 1). Each watershed represents a population. Within each population, there may be several subpopulations at specific locations within the watershed.

^c Data from Miners (2015, unpub data).

^d Data from Pearson (2015, unpub. data).

^e Howe’s Creek is considered to be part of the Bertrand mainstem subpopulation in the Bertrand Creek Watershed.

^f All locations within the Chilliwack Delta are considered to be a part of the Chilliwack Delta watershed population. Throughout the document, Chilliwack Delta refers to Luckakuck Creek, Semmihault Creek, Atchelitz Creek, Little Chilliwack Creek Mainstem and Interception Ditch.

In the current landscape, there are no aquatic connections between adjacent populations within Canada except for a small headwater pond that feeds both Mountain Slough and Miami Creek and an ephemeral high water connection between Bertrand Creek and the Salmon River via a headwater wetland (M. Pearson pers. comm. 2010). The only other route between watersheds is via the mainstem Fraser River or Nooksack River, although no Salish Sucker have ever been reported from either and captures in larger sloughs are extremely rare (M. Pearson pers. comm. 2010). Prior to the drainage of Sumas Lake in Abbotsford (1920s) and the construction of the dyke system following the 1948 Fraser River flood, permanent and high water connections among populations would have been more common.

The Salish Sucker is also known in seven watersheds in northwestern Washington State (COSEWIC 2012). Range-wide, the Salish Sucker has been in decline since at least the 1960s (McPhail 1987; Pearson 2004; DFO 2015).

4.3 Needs of the species

Biological needs, ecological role, and limiting factors

The Salish Sucker inhabits headwater streams and small sloughs where habitat conditions vary widely on daily, seasonal, and longer time scales. They tolerate higher temperatures and lower dissolved oxygen levels than most other native fish that occur in this region of B.C. The major limiting factor for populations is the availability of high quality habitat. Salish Sucker have life history characteristics that promote rapid population growth, given adequate habitat (Pearson and Healey 2003). Compared to Longnose Sucker, the Salish Sucker is small, short-lived, and early-maturing. The species is a broadcast spawner. Most spawn for the first time in their second year, and they rarely live beyond five years (McPhail 1987). Spawning occurs between early April and mid-July (McPhail 1987; Pearson and Healey 2003), and egg incubation is likely complete by mid-August.

Aquatic habitat

Adults are most abundant in marshes and American Beaver (Castor canadensis) ponds with mud or silt substrates. The proportion of channel deeper than 70 cm is the strongest predictor of adult presence in a reach (Pearson 2004). Occupied reaches also have significantly less riffle and more in-stream vegetation than reaches in which Salish Sucker are absent. Young-of-the-year are associated with shallow pool and glide^{Footnote 3}  habitats containing abundant vegetation (Pearson 2004). Spawning typically occurs in gravel riffles, but groundwater upwellings in rocky substrate are likely used in systems lacking riffle habitats (M. Pearson pers. obs.). Most individuals appear to have small home ranges (mean of 170 m of channel) although some individuals are known to move kilometers during the spawning period (Pearson and Healey 2003).

Salish Sucker tolerate low oxygen environments and have occasionally been captured in areas with concentrations below 2 mg/L (Pearson unpublished data). Sublethal effects including reduced growth and fecundity likely occur at these concentrations. Based on observation, appropriate targets for dissolved oxygen is ≥4 mg/L for adults and ≥6.5 mg/L for eggs and fry (M. Pearson, pers. comm. 2017). For adults, this is lower than the federal water quality guideline for aquatic life (5 mg/L for adults; CCREM 2015), but the guidelines are intended to protect species like salmonids, which are very intolerant of hypoxia. For early life stages, the federal water quality guideline for early life history stages in warm water streams is used (6.5 mg/L; CCREM 2015). As no data are available for Salish Sucker requirements, this guideline is considered appropriate for Salish Sucker (Pearson 2004). Tolerances of pH are unknown for Salish Sucker or Longnose Sucker, but the White Sucker (Catostomus commersoni) shows sublethal effects on reproduction at pH<5.6 and complete mortality at pH<4.3.

Riparian habitat

Riparian habitat is important for maintaining instream habitat features necessary to support Salish Sucker spawning, incubation, rearing and feeding. Benthic insectivores like Salish Sucker are among the most sensitive fish species to loss of wooded riparian areas (Stauffer et al. 2000), probably due to the impacts of riparian loss on siltation and macroinvertebrate community structure (Kiffney et al. 2003; Allan 2004). Riparian habitat helps control sediment entry to streams from overland flow, prevents excessive bank erosion and buffers stream temperatures. Failure to maintain adequate riparian habitats can cause population-level impacts. For example, an absence of shade from overhanging or canopy vegetation may increase water temperatures to harmful levels (>23°C) and result in reduced fitness and mortality of individuals (Lynch et al. 1984; Richardson et al. 2010). Increased erosion due to poorer bank stability can cause sediment deposition in riffles, leading to increased embeddedness, decreased interstitial habitat, impaired spawning and incubation, and decreased invertebrate prey abundance (Richardson et al. 2010).

Location of habitats

Distribution of the Salish Sucker is clumped, with a few sites harbouring most individuals (Pearson 2004). These ‘hotspots’ likely result from rare convergences of optimal levels in a few key environmental variables (Brown et al. 1995). For Salish Sucker these variables likely include extensive areas of deep water (100s of square metres of channel) close to spawning riffles and shallow nursery habitat, adequate water quality, and low predation pressure (Pearson 2004). Most individuals appear to confine their movements to a single reach but some individuals travel more widely (Pearson and Healey 2003). Clumped distribution and bimodal movement patterns suggest that metapopulation and/or source-sink population dynamics characterize the species. If so, factors affecting migration between sub-populations (the proximity of hotspots to one another and the occurrence of movement barriers between them) are likely important to long-term population viability. Natural disturbance and succession may produce a pattern in which the location of hotspots moves throughout the landscape over time, but are occasionally eliminated by catastrophic events (Ives and Klopper 1997). Such catastrophic declines at the reach scale have been documented for the Salish Sucker (Pearson 2004), but the effect on extinction risk for Salish Sucker populations is unknown.

5 Threats

5.1 Threat assessment

An assessment and prioritization of threats to survival and recovery of the Salish Sucker was undertaken in the RPA (DFO 2015) and was based on an earlier work by Pearson (2004). For more details on the threat assessment process, refer to the Guidance on Assessing Threats, Ecological Risk and Ecological Impacts for Species at Risk (DFO 2014). Assessment category definitions are provided in footnotes to the tables and appendix C.

In this recovery strategy, the threat assessment has been updated and revised in accordance with a two-step process, which first characterizes threats at the population (watershed) level and then at the whole Canadian range level. Population level threats analyses for each of the 11 populations appear in appendix D. The Canadian range level threat assessment is presented in table 4.

Seven threats were identified based on knowledge of species biology and habitat conditions across the Canadian range in the RPA (DFO 2015). The threats are: hypoxia, seasonal lack of water, harmful substances, sediment deposition, habitat fragmentation, physical destruction of habitat, and introduction of aquatic invasive species. The revised assessment resulted in changed (mostly elevated) risk levels for a number of threats, including seasonal lack of water, harmful substances and habitat fragmentation.

The most widespread and highest risk threat to Salish Sucker across its Canadian range is severe hypoxia. It degrades areas of otherwise suitable habitat, can kill large numbers of fish quickly, has numerous contributing factors, can easily go undetected, and appears to be occurring with increasing frequency and intensity across watersheds containing Salish Sucker (Pearson 2004; DFO 2015). Seasonal lack of water, harmful substances, sediment deposition, habitat fragmentation and physical destruction of habitat are also considered high risk threats range wide (table 4), but are less pervasive than hypoxia (appendix D). Aquatic invasive species are considered a medium risk threat but are poorly understood.

^g The specific assessment categories and associated rankings definitions for population-level threats are provided in Appendices C and D. Canadian range level threats are a roll-up of population level threats.

^h Canadian range level threat risk: the highest level of risk for a given population, based on the likelihood and level of impact of a population-level threat

ⁱ Canadian range level threat occurrence: the timing of occurrence of the threat; may be any combination of historical, current and/or anticipatory representing all categories that have been identified in the population-level assessment

^j Canadian range level threat frequency: the temporal extent of the threat representing all categories that have been identified in the population-level assessment

^k Canadian range level threat extent: the proportion of the species affected by the threat

5.2 Description of threats

Hypoxia

Hypoxia, or the presence of low oxygen levels in water, is the most serious threat to Salish Sucker populations in Canada and is considered a high risk threat in every occupied watershed (table 4; appendix D). Occasional reach-scale kills of Salish Sucker due to severe hypoxia are believed to occur. Hypoxia is a seasonal threat, with maximum severity and spatial extent occurring under drought conditions in summer and early fall. Up to two-thirds of critical habitat length is hypoxic, with 45 percent being severely hypoxic (Pearson 2015a). For assessment purposes, areas with dissolved oxygen levels between 2.5 and 4 mg/L are considered moderately hypoxic and likely to cause some impairment of key life history functions. Areas containing less than 2.5 mg/L of dissolved oxygen are considered severely hypoxic and likely to be lethal over the short term or cause severe impairments to key life history functions.

Hypoxia is caused by the cumulative effects of local and watershed-scale impacts. Nutrients in Fraser Valley groundwater and streams are elevated, primarily as a consequence of over-application of manure and fertilizers to agriculture lands (Lavkulich et al. 1999; Schreier et al. 2003), but also from urban stormwater runoff and faulty septic systems (Lavkulich et al. 1999). Such nutrient loading has increased greatly with ongoing agricultural intensification in the Fraser Valley (Schöne et al. 2006; Schindler et al. 2006). Increased nutrients result in algal blooms and rampant growth of plants that deplete oxygen levels at night. Decomposition of dead vegetation may severely depress daytime oxygen levels as well. Further, hypoxia may be exacerbated by the removal of riparian vegetation because shade provided by riparian vegetation helps maintain lower water temperatures. Warmer water has less capacity for dissolved oxygen and increases the metabolic demands of fish and other organisms. In addition, reduced water movement impairs re-oxygenation of water and may be caused by channelization (Schreier et al. 2003), beaver ponds (Fox and Keast 1990; Schlosser and Kallemyn 2000) or low flows.

Seasonal lack of water

Seasonal lack of water is considered a high risk threat to Salish Sucker in Canada (table 4). At the population level, it is considered a high risk threat in Bertrand Creek, Little Salmon River, Salmon River and Salwein Creek/Hopedale Slough (appendix D). In addition, Fishtrap Creek historically experienced extensive impacts of low flow. The natural vulnerability of these watersheds to reduced flow is exacerbated by human water use for irrigation and domestic use, which peaks during the late-summer low flow period. Common land use changes that involve installing and maintaining drainage infrastructure (for example, urbanization, agricultural drainage) also tend to exacerbate problems with water availability during dry periods.

The deep pool habitats preferred by Salish Sucker rarely dry out completely, and spawning and egg incubation occur in spring and early summer, when water is generally plentiful. Extreme low flows in the late summer, however, exacerbate other threats including hypoxia, sediment deposition, habitat fragmentation and predation (COSEWIC 2012; DFO 2015).

Harmful substances

Harmful substances are considered a high risk threat to Salish Sucker in Canada (table 4). At the population level, it is considered a high risk threat in Salwein Creek/Hopedale Slough (appendix D). In the Salwein Creek/Hopedale Slough watershed, there is a risk of railway spills and polycyclic aromatic hydrocarbon contamination (Pearson 2017).

Pathways for the introduction of harmful substances to Salish Sucker habitats include urban storm runoff, contaminated groundwater, direct industrial discharges, aerial deposition, and accidental spills (Hall et al. 1991; Schreier et al. 2003; COSEWIC 2012). Some contaminants, particularly heavy metals, bind to sediments where they may be taken up and bioaccumulated by aquatic invertebrates and subsequently bottom-feeding fish, like Salish Sucker. Data on threshold concentrations for lethal and sublethal effects to the Salish Sucker are lacking. As a bottom-dwelling species they may be sensitive to contaminants bound to sediment as well as those in food items and the water column. Salish Sucker are less likely to be found in reaches where land use within 200 m of the channel is predominantly urban, which may be linked, in part, to harmful substances entering habitat via stormwater runoff (Pearson 2004). The U.S. Environmental Protection Agency lists the closely related Longnose Sucker as having “intermediate” pollution tolerance (EPA 2012).

Sediment deposition

Sediment deposition is considered a high risk threat to Salish Sucker in Canada (table 4). At a population level, it is considered a high risk threat in Fishtrap Creek and Mountain Slough, and a medium risk threat in Agassiz Slough, Bertrand Creek, Chilliwack Delta, Elk Creek/Hope Slough, Miami River, Pepin Creek and Salmon River (appendix D). Significant events where spawning riffles have been clogged with sediment originating from in-stream projects occur regularly in association with drainage maintenance and other in-stream works, particularly in Mountain Slough, Chilliwack Delta, Elk Creek/Hope Slough and Salwein Creek. Major events where gravel pits have filled in pools and largely eliminated instream cover have occurred several times in Pepin Creek (Pearson 2004). Chronic sedimentation occurs in most watersheds in areas lacking riparian vegetation, especially where fields are ploughed to top of bank and around storm sewer discharges.

Sediment deposition is increased by direct discharges, storm runoff and bank erosion, and is accelerated by lack of riparian vegetation and increased peak flows (Waters 1995). All of these factors have increased with urban, agriculture and mining development in Salish Sucker watersheds (COSEWIC 2012; DFO 2015). Impacts include smothering eggs and reducing food (macroinvertebrate) availability. Salish Sucker spawn in riffles between early April and mid-July (Pearson and Healey 2003) and are probably most susceptible to sedimentation in these habitats during this period.

Habitat fragmentation

Habitat fragmentation is considered a high risk threat to Salish Sucker in Canada (table 4). Some fragmentation has occurred within almost all occupied watersheds. At the population level, it is a high risk threat in Agassiz Slough and a medium risk threat in Bertrand Creek, Chilliwack Delta, Elk Creek/Hope Slough, Fishtrap Creek, Salmon River and Salwein Creek/Hopedale Slough (appendix D). It is particularly concerning in Agassiz Slough and upper Bertrand Creek where impassible culverts prevent fish from escaping areas of severe hypoxia during late summer. Three tributaries to Fishtrap Creek that contain suitable habitat but lack Salish Sucker are inaccessible due to perched culverts (Pearson unpub. data). There is also evidence of beaver dams fragmenting habitat in Tyre Creek (Salmon River tributary). At the Canadian range scale, most high-water connections between watersheds have been lost or weakened to dykes and drainage. Such connections between watersheds during floods were much more common prior to the extensive dyking and drainage works of the 20th century.

Most barriers and habitat fragmentation in Salish Sucker watersheds date from the past 50 to 130 years, and surviving populations have shown some resilience (Pearson 2004). The effects of reduced movement between subpopulations within watersheds and reduced ability to colonize new habitat due to physical barriers and degraded habitat, however, may occur over longer time frames (COSEWIC 2012). In addition, the other threats may fragment habitat by preventing or curtailing movement of fish within and among affected reaches.

Physical destruction of habitat

Physical destruction of habitat is considered a high risk threat to Salish Sucker in Canada (table 4). It occurs regularly in the majority of watersheds occupied by Salish Sucker. At the population level, it is a high risk threat in the Chilliwack Delta, Elk Creek/Hope Slough and Mountain Slough (appendix D). Historically, physical destruction of habitat was likely the most significant of the identified threats across Salish Sucker’s Canadian range. Approximately 77 percent of pre-settlement wetland areas in the Fraser Valley have been drained or infilled (Boyle et al. 1997). The drainage of Sumas Lake (80 to 100 km²) and associated wetlands in the 1920s was the largest single historical incident (Woods 2001). Fifteen percent of the area’s streams no longer exist, having been paved over or piped (DFO 1998). A large but unknown proportion of those that remain have been channelized and/or repeatedly dredged for agricultural or urban development. Dredging of channels for flood control and agricultural drainage still occurs annually in most watersheds known to have Salish Sucker.

Physical destruction of habitat may occur through channelization, channel maintenance, dredging and infilling activities that directly destroy or degrade stream habitats. The aquatic vegetation required by adult Salish Sucker and the riffle habitat required for spawning and incubation may be targeted for removal or alteration in drainage projects.

Physical destruction of habitat may also occur through the removal of riparian vegetation and may impact Salish Sucker throughout its Canadian range. Riparian vegetation helps control sediment entry to the stream from overland flow, prevents excessive bank erosion and buffers stream temperatures, reduces nutrient loading, and provides terrestrial insects for drift-feeders in streams. Removal of riparian vegetation can also exacerbate other threats, including sediment deposition.

Increased predation from aquatic invasive species

Increased predation from aquatic invasive species is considered a medium risk threat to Salish Sucker in Canada (table 4). At the population level, it is considered a medium risk threat in Bertrand Creek, Chilliwack Delta, Elk Creek/Hope Slough, Fishtrap Creek, Little Campbell River, Pepin Creek and Salwein Creek/Hopedale Slough (appendix D). Introduced predators inhabit every stream known to contain Salish Sucker but the extent of impacts on populations is unknown. Salish Sucker have coexisted with introduced predators, including Largemouth Bass (Micropterus salmoides), Brown Bullhead (Ameiurus nebulosus), and Bullfrog (Lithobates catesbaena) for more than twenty years in parts of their range (Pearson 2004; COSEWIC 2012). All of these species are known to have caused extirpations and extinctions in native fish populations elsewhere (Miller et al. 1989; Hatfield 2001). Impacts may increase when distribution is restricted due to hypoxia or seasonal lack of water or if a new predator is introduced (COSEWIC 2012).

6 Population and distribution objectives

Population and distribution objectives establish, to the extent possible, the number of individuals and/or populations, and their geographic distribution, that is necessary for the recovery of the species. The population and distribution objectives for the Salish Sucker are:

Population objective

Long-term: reach or exceed watershed-specific population objectives identified in table 5 by 2035.

Rationale: separate recovery targets are required for each population because they are isolated from one another with a very low probability of immigration to prevent or recolonization to reverse extirpation. Insufficient information is available to quantitatively estimate the minimum viable population (MVP) size for Salish Sucker. Based on reviews of MVP estimates for a wide range of vertebrates, target values in the low to mid thousands are considered appropriate (DFO 2015).

Salish Sucker life history characteristics are conducive to rapid population growth under favourable conditions (Pearson and Healey 2003). The key factor in recovery will be the attenuation of severe hypoxia across the range; which will require dramatic reductions in agricultural nutrient loading and significant increases in riparian shading. Two decades is likely required to achieve this long-term objective. No additional net loss of habitat is also assumed.

^l From COSEWIC 2012; Pearson 2016

Distribution objectives

Short-term: continued persistence in all eleven currently occupied watersheds.

Long-term: presence in all critical habitat reaches.

7 Broad strategies and general approaches to meet objectives

7.1 Actions already completed

Research and monitoring

DFO, B.C. Ministry of Environment (B.C. MOE), Pearson Ecological, the University of British Columbia (UBC), Western Washington University, A Rocha Canada, Cheam Indian Band, Leq'á:mel First Nation, Seyem'Qwantlen, Matsqui First Nation, Metro Vancouver Regional Parks, the District of Kent, the Township of Langley, the City of Chilliwack, the City of Abbotsford, the B.C. Ministry of Transportation and Infrastructure, and consultants on behalf of proponents have all contributed to research and monitoring activities through various mechanisms, including the Aboriginal Fund for Species at Risk and the Habitat Stewardship Program. Sampling has included: opportunistic weight and length measurements; sampling as part of mandatory fish salvages or pre- and post-construction monitoring; water quality measurements; population estimates; reconnaissance sampling to document unknown populations; mapping potential critical habitat; monitoring tagged individuals and their distribution; studying the effects of hypoxia and land use; genetics research; and habitat suitability assessments.

Habitat restoration

Experimental habitat restoration work targeting the Salish Sucker was initiated by UBC researchers in cooperation with local stewardship groups and landowners in 1999. Population size and habitat conditions have been monitored repeatedly at two sites in the Pepin Brook watershed (Patton 2003; Pearson unpub data). Using this information, additional projects have been constructed in Salwein Creek and Hopedale Slough, Mountain Slough, Bertrand Creek, and the Salmon River by Dr. Mike Pearson, working in cooperation with DFO, the Township of Langley and the District of Kent.

Several organizations conducted habitat restoration activities, including (among others): DFO (in Hope Slough), the British Columbia Conservation Foundation (in Aldergrove Regional Park), Langley Environmental Partners Society (in the Salmon River and Bertrand Creek watersheds), and A Rocha Canada (in the Little Campbell River watershed) and Fraser Valley Watersheds Coalition (in Hope Slough and Chilliwack Delta). Consultants also conducted compensatory habitat restoration in Pepin Brook on behalf of proponents. Dr. Mike Pearson assisted with many of these restoration initiatives.

Integrated channel maintenance pilot projects

In 2003, the City of Chilliwack initiated a pilot project integrating drainage maintenance and fish habitat restoration in Salwein Creek. Hand maintenance protocols and shade from riparian zone plantings reduce the need for machine cleaning of waterways for drainage. Expansion of this program to other watersheds and jurisdictions would be beneficial to the Salish Sucker.

Riparian planting

Since 2000, native plants and livestock fencing have been provided and installed for landowners of riparian habitats along reaches containing the Salish Sucker in Agassiz Slough, Mountain Slough, Miami River, Salmon River, Bertrand Creek, Pepin Brook, the Little Chilliwack River, Elk Creek and Hope Slough. Much of this work has been done by community volunteers organized by three local stewardship groups (Langley Environmental Partners Society, Fraser Valley Watersheds Coalition and Fraser Harrison Smart Growth) working in cooperation with Dr. Mike Pearson. Through various mechanisms, local governments such as the District of Kent, City of Chilliwack, and the Township of Langley have provided support and/or partnership for such projects.

Landowner contact and public education programs

The Langley Environmental Partners Society and the Fraser Valley Regional Watersheds Coalition implemented landowner contact programs in cooperation with DFO and others in all watersheds currently inhabited by the Salish Sucker between 2001 and 2010. Public information meetings were also held in each watershed. Colour display posters on Salish Sucker have also been given to stewardship groups in Chilliwack, Langley and Agassiz for use during public events. Dr. Mike Pearson has provided lectures and habitat enhancement site tours featuring the Salish Sucker and recovery efforts to local schools, universities and stewardship groups through the Langley Environmental Partners Society.

The Langley Environmental Partners Society, A Rocha Canada, Cheam Indian Band, Leq'á:mel First Nation, Seyem'Qwantlen, and Matsqui First Nation have all contributed to education and outreach initiatives through various mechanisms, for example: distribution of print materials, presentations, development of conservation planning documents, and discussions with targeted groups or individuals. The Stewardship Centre for BC published stewardship practices on their "Roles of Local Government” website for Riparian Areas in Settled Landscapes, Guidance for Restoration Activities in Riparian Areas, and Drainage Maintenance in Agricultural Waterways.

7.2 Strategic direction for recovery

A description of the broad strategies to address identified threats and of the research and management approaches needed to meet population and distribution objectives is presented in table 6. These informed the development of specific recovery measures in the action plan for the Nooksack Dace (Rhinichthys cataractae) and the Salish Sucker (Catostomus sp.) in Canada (DFO 2017).

Broad strategy 1: inventory and monitoring
Broad strategy 2: research
Broad strategy 3: management and coordination
Broad strategy 4: stewardship and outreach
Broad strategy 5: international collaboration

Table 6. Recovery planning table.

^m Priority” reflects the degree to which the approach contributes directly to the recovery of the species or is an essential precursor to an approach that contributes to the recovery of the species:

• "high" priority approaches are considered likely to have an immediate and/or direct influence on the recovery of the species
• "medium" priority approaches are important but considered to have an indirect or less immediate influence on the recovery of the species
• "low" priority approaches are considered important contributions to the knowledge base about the species and mitigation of threats

8 Critical habitat

8.1 Identification of the species’ critical habitat

8.1.1 General description of the species’ critical habitat

Critical habitat is defined in SARA as

“…the habitat that is necessary for the survival or recovery of a listed wildlife species and that is identified as the species’ critical habitat in the recovery strategy or in an action plan for the species.” [s. 2(1)]

Also, SARA defines habitat for aquatic species as

“… spawning grounds and nursery, rearing, food supply, migration and any other areas on which aquatic species depend directly or indirectly in order to carry out their life processes, or areas where aquatic species formerly occurred and have the potential to be reintroduced.” [s. 2(1)]

For the Salish Sucker, critical habitat is identified to the extent possible, using the best available information, and provides the functions and features necessary to support the species’ life-cycle processes and to achieve the species’ population and distribution objectives.

This recovery strategy identifies aquatic critical habitat for Salish Sucker as relatively homogenous segments of stream demarcated by distinct geomorphic or land use transitions, otherwise known as reaches, within the Little Campbell River, Salmon River, Bertrand Creek, Pepin Brook, Fishtrap Creek, Salwein Creek/Hopedale Slough, Chilliwack Delta, Elk Creek/Hope Slough, Mountain Slough, Agassiz Slough and Miami River watersheds.

More specifically, critical habitat includes the reaches within those watersheds that consist of more than 50 m of continuous pool with a water depth exceeding 70 cm under summer low flow conditions. Critical habitat within these reaches includes all the aquatic habitats, including features and attributes identified in section 8.1.3, and all riparian areas on both banks for the entire length of the identified aquatic reaches. Riparian critical habitat is continuous and extends laterally (inland) from the top of bank to a width equal to the widest zone of sensitivity calculated for five riparian features and functions.

It is unknown if the critical habitat identified in this recovery strategy is sufficient to achieve the species’ population and distribution objectives. The schedule of studies outlines the research required to identify additional critical habitat and acquire more detailed information about the critical habitat identified to achieve the species’ population and distribution objectives.

8.1.2 Information and methods used to identify critical habitat

Defining critical habitat reaches

Critical habitat for the Salish Sucker was defined using in-stream habitat characteristics at the scale of the reach, a natural unit of stream habitat that ranges from hundreds to thousands of metres in length (Frissell et al. 1986). There are three reasons for adopting this scale. First, the reach scale corresponds to the distribution of subpopulations within the 11 occupied watersheds and usually contains all habitat types used during the life cycle (Pearson 2004). Second, the ‘channel units’ of critical habitat (riffles and pools) are dynamic and frequently move during flood events in these streams. Effective protection and management of critical habitat in these circumstances must allow for normal channel processes and must, therefore, occur at a spatial scale larger than the channel unit. The reach scale is the next largest in accepted stream habitat classifications (Frissell et al. 1986; Imhof et al. 1996) and by definition represents relatively homogenous segments of stream demarcated by distinct geomorphic or land use transitions. Third, the reach scale corresponds most closely to that of land ownership in these watersheds.

Defining aquatic critical habitat areas

The protocol used to identify Salish Sucker critical habitat was consistent with guidelines for documenting habitat quality and use by freshwater fishes at risk (Rosenfeld and Hatfield 2006; DFO 2007) and the approach and results were peer-reviewed (Pearson 2008). Additions of new critical habitat reaches were informed from Pearson 2013, 2014, 2016 and unpub. data. The amount of critical habitat required to achieve population targets depends upon its quality, its extent, and its spatial configuration on the landscape (Rosenfeld and Hatfield 2006). For all eleven Salish Sucker populations the total amount of suitable habitat available is considered necessary to meet population and distribution objectives (Pearson 2015b).

Defining riparian critical habitat areas

The identification of riparian critical habitat was informed by Pearson 2008 and expert opinion. Critical habitat includes all riparian areas on both stream banks for the entire length of the identified aquatic reaches. The required widths of riparian critical habitat vary among sites and are defined in reach scale assessments. Riparian vegetation must be of sufficient width to control sediment entry to the stream from overland flow, to prevent excessive bank erosion and to buffer stream temperatures. The effectiveness of riparian vegetation in preventing materials (for example, sediment, nutrients, harmful substances) from entering a stream depends strongly on its longitudinal continuity and lateral width (Weller et al. 1998). Consequently, riparian vegetation adjacent to aquatic critical habitat reaches should be continuous and sufficiently wide.

Widths of riparian critical habitat for Salish Sucker were assessed using a spatially referenced methodology adapted directly from and consistent with the British Columbia Riparian Areas Regulation (RAR) (Riparian Areas Protection Act [S.B.C. 1997, c. 21], Province of British Columbia 2006). The B.C. MOE and DFO developed and implemented this methodology for determining riparian vegetation widths required to maintain riparian function and protect fish habitat. The RAR was developed to protect “salmonids, game fish, and regionally significant fish” from the impacts of land development. In the absence of data on riparian habitat needs for a SARA-listed species, this is a reasonable standard to apply in the identification of critical habitat because it represents a benchmark and standard methodology to which both federal and provincial agencies responsible for management of species at risk have already agreed.

The identified width of the riparian critical habitat for each reach is equal to the widest zone of sensitivity (ZOS) calculated for each of five riparian features and functions: large woody debris supply for fish habitat and maintenance of channel morphology; localized bank stability; channel movement; shade; and, insect and debris fall. The ZOS values are calculated using methods consistent with those used under the RAR. The width of existing riparian vegetation and areas where riparian width is restricted by permanent structures (for example, roads, buildings, yards) were also assessed. Further details of methods and an assessment of existing riparian vegetation in these areas can be found in Pearson (2008).

8.1.3 Identification of critical habitat

Geographic information

Salish Sucker distribution falls within 11 watersheds, including Little Campbell River, Bertrand Creek, Pepin Creek, Fishtrap Creek, Salmon River, Chilliwack Delta, Elk Creek/Hope Slough, Salwein Creek/Hopedale Slough, Mountain Slough, Agassiz Slough and Miami River.  Identified critical habitat within these watersheds totals 196.5 km of channel and 818.2 hectares of adjoining riparian habitats. Maps delineating critical habitats are provided in appendix E and geographic coordinates of the starts and ends of each critical habitat reach are provided in appendix F.

The locations of the critical habitat’s functions, features and attributes have been identified using the Critical Habitat Parcel approach for both the aquatic and riparian components of critical habitat. This means that aquatic and riparian critical habitat is the exact area delineated by the identified boundaries.

Biophysical functions, features and attributes

Table 7 summarizes the best available knowledge of the functions, features and attributes for each life stage of the Salish Sucker within the identified geographic locations (refer to section 4.3 ‘Needs of the species’ for full references). Note that not all attributes in table 7 must be present in order for a feature to be identified as critical habitat. If the features as described in table 7 are present and capable of supporting the associated function(s), the feature is considered critical habitat for the species, even though some of the associated attributes might be outside of the range indicated in the table.

ⁿ Function: a life-cycle process of the listed species taking place in critical habitat (for example, spawning, nursery, rearing, feeding and migration).

^o Feature: features describe how the habitat is critical and they are the essential structural component that provides the requisite function(s) to meet the species’ needs. Features may change over time and are usually comprised of more than one part, or attribute. A change or disruption to the feature or any of its attributes may affect the function and its ability to meet the biological needs of the species.

^p Attribute: attributes are measurable properties or characteristics of a feature. Attributes describe how the identified features support the identified functions necessary for the species’ life processes.

Deep pool habitat

As the main feeding and rearing habitat for adult and larger juveniles (individuals with fork length >7 cm), deep pools are the primary habitat for the majority of the life cycle. Salish Sucker are concentrated in reaches containing at least one pool that exceeds 70 cm in depth at low flow for a minimum of 50 metres (Pearson 2004). All reaches across Salish Sucker’s Canadian range that contain such habitat are identified as critical habitat. This includes reaches where severe hypoxia appears to currently limit Salish Sucker numbers.

Riffle habitat

Riffle habitats are used by Salish Sucker for spawning and incubation. Riffles tend to be rare (and potentially limiting) in the reaches occupied by high densities of Salish Sucker, which consist predominantly of headwater ponds and marshes (Pearson 2004). Consequently, all riffle habitats within reaches containing more than 50 m of habitat with water depths exceeding 70 cm (deep pool habitat) are identified as critical habitat. In some watersheds, fish leave their ‘home’ reach to spawn (Pearson and Healey 2003). The riffles known as spawning sites are within identified critical habitat reaches but other undocumented spawning sites outside identified critical habitat may exist.

Shallow pool and glide habitats

Shallow pools and glides less than 40 cm in depth are used by young-of-the-year Salish Sucker (<7 cm fork length) as a nursery habitat for feeding and rearing, although they are occasionally captured in deeper water (Pearson 2004). All shallow pool and glide habitats within reaches that contain more than 50 m of continuous habitat and water depths exceeding 70 cm (deep pool habitat) are identified as critical as it is potentially limiting as nursery habitat.

Riparian habitats

All riparian vegetation in identified riparian critical habitat reaches protects the integrity of in-stream critical habitat. Failure to maintain adequate riparian vegetation as part of critical habitat is likely to result in sediment deposition (Waters 1995). Sediment deposition may result in infilling of the interstitial spaces in coarse substrate that Salish Sucker occupy during spawning and incubation. Nutrient loading will be higher in reaches without adequate riparian vegetation (Martin et al. 1999; Dhondt et al. 2002; Lee et al. 2003) and is likely to contribute to hypoxia through eutrophication. Solar radiation in nutrient rich reaches lacking adequate riparian shading will also contribute to eutrophication and hypoxia (Kiffney et al. 2003). In habitats lacking sufficient flow or groundwater, absence of shade may also increase water temperatures to harmful levels.

The effectiveness of riparian vegetation in preventing materials (sediment, nutrients, harmful substances, etc.) from entering a stream depends strongly on its longitudinal continuity and its lateral width (Weller et al. 1998). Consequently, riparian vegetation in critical habitat reaches should be continuous and sufficiently wide. Riparian vegetation as narrow as 5 m provides significant protection from bank erosion and sediment deposition from overland flow. At least 10 m are required to maintain levels of terrestrial food inputs similar to those of forested landscapes. More than 30 m of riparian vegetation may be required to fully mitigate warming water temperatures g (Brown and Krygier 1970; Lynch et al. 1984; Castelle et al. 1994) and siltation, and for long-term maintenance of channel morphology.

Riparian vegetation upstream of critical habitat is important in minimizing sedimentation and other impacts within critical habitat. For this reason stewardship programs should promote the establishment of continuous riparian vegetation throughout the watershed, not just along critical habitat reaches.

Summary of critical habitat relative to population and distribution objectives

These are areas that, based on current best available information, the Minister of Fisheries and Oceans considers necessary to partially achieve the species’ population and distribution objectives required for the survival and recovery of the species. Additional critical habitat may be identified in future updates to the recovery strategy.

8.2 Schedule of studies to identify critical habitat

Further research is required to identify additional critical habitat and refine the understanding of the functions, features and attributes of the currently identified critical habitat necessary to support the species’ population and distribution objectives and protect the critical habitat from destruction. Table 8 outlines further research required to identify and refine critical habitat.

8.3 Examples of activities likely to result in the destruction of critical habitat

Under SARA, critical habitat must be legally protected from destruction within 180 days of being identified in a final recovery strategy or action plan and included in the Species at Risk Public Registry. For the Salish Sucker critical habitat identified in the 2016 recovery strategy (DFO 2016), legal protection was accomplished on August 7, 2019 through a SARA Critical Habitat Order made under subsections 58(4) and (5), which invoked the prohibition in subsection 58(1) against the destruction of the identified critical habitat. This amended recovery strategy includes updates to critical habitat identification.

The following examples of activities likely to result in the destruction^{Footnote 4} of critical habitat (table 9) are based on known human activities that are likely to occur in and around critical habitat and would result in the destruction of critical habitat if unmitigated. The list of activities is neither exhaustive nor exclusive and has been guided by the threats described in section 5. The absence of a specific human activity from this table does not preclude or restrict the Department’s ability to regulate that activity under SARA. Furthermore, the inclusion of an activity does not result in its automatic prohibition, and does not mean the activity will inevitably result in destruction of critical habitat. Every proposed activity must be assessed on a case-by-case basis and site-specific mitigation will be applied where it is available and reliable. Where information is available, thresholds and limits have been developed for critical habitat attributes to better inform management and regulatory decision making. However, in many cases knowledge of a species and its critical habitat’s thresholds of tolerance to disturbance from human activities are lacking and must be acquired.

9 Measuring progress

The performance indicators presented below provide a way to define and measure progress toward achieving the population and distribution objectives. A successful recovery program will achieve the overall aim of reaching or exceeding watershed specific abundance targets and restoring Salish Sucker presence to all critical habitat reaches. Progress towards meeting these objectives will be reported on in the Report on the Progress of Recovery Strategy Implementation.

9.1 Distribution performance indicators

Salish Sucker is present in:^{Footnote 5}

• all reaches that have been identified as critical habitat in each watershed, which indicates recovery of a watershed’s population distribution
• all reaches that have been identified as critical habitat across all eleven occupied watersheds in B.C., which indicates recovery of the Salish Sucker distribution in Canada

9.2 Population performance indicators

Salish Sucker is found at abundance levels corresponding with population targets, where:^{Footnote 6}

• the population target for each watershed is met or exceeded, which indicates recovery of that watershed’s population abundance
• the population targets across all eleven occupied watersheds in B.C. are met or exceeded, which indicates recovery of Salish Sucker in Canada

10 Statement on action plans

The federal government’s approach to recovery planning is a two-part approach. The first part is the recovery strategy and the second part is the action plan. An action plan contains specific recovery measures or activities required to meet the objectives outlined in the recovery strategy.

The Action Plan for the Nooksack Dace (Rhinichthys cataractae) and the Salish Sucker (Catostomus sp.) in Canada (DFO 2017) was posted on the Species at Risk Public Registry on April 26, 2017.

11 References

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Appendix A: effects on the environment and other species

In accordance with the Cabinet Directive on the Environmental Assessment of Policy, Plan and Program Proposals (2010), SARA recovery planning documents incorporate strategic environmental assessment (SEA) considerations throughout the document. The purpose of a SEA is to incorporate environmental considerations into the development of public policies, plans, and program proposals to support environmentally sound decision-making and to evaluate whether the outcomes of a recovery planning document could affect any component of the environment or achievement of any of the Federal Sustainable Development Strategy’s goals and targets.

Recovery planning is intended to benefit species at risk and biodiversity in general. However, it is recognized that strategies may also inadvertently lead to environmental effects beyond the intended benefits. The planning process based on national guidelines directly incorporates consideration of all environmental effects, with a particular focus on possible impacts upon non-target species or habitats. The results of the SEA are incorporated directly into the strategy itself, but are also summarized below in this statement.

While this recovery strategy will clearly benefit the environment by promoting the recovery of Salish Sucker, potential effects on other species were also considered. The strategy calls for the protection, creation, and enhancement of deep pool and marsh habitat, which could alter habitats required by species at risk such as Nooksack Dace, Western Painted Turtle (Chrysemys picta bellii), Oregon Spotted Frog (Rana pretiosa) and others, as well as other fish species, including Steelhead (Oncorhynchus mykiss), Cutthroat Trout (Oncorhynchus clarkia clarkii) and Coho Salmon (Oncorhynchus kisutch). The recovery strategy recommends cooperation with local stewardship groups and agency staff on habitat management. DFO addressed needs for recovery of Nooksack Dace and Salish Sucker together by coordinating recovery activities for both species in watersheds where they coexist through the development of a joint action plan (DFO 2017). The recovery strategy also calls for minimizing probability of predatory aquatic invasive species introductions, by documenting their occurrence and educating the public on their impacts, which could provide benefits to other species that could be affected by introduced predators. Taking these approaches into account, it was concluded that the benefits of this recovery strategy far outweigh any adverse effects that may result.

Appendix B: record of cooperation and consultation

Recovery strategies are to be prepared in cooperation and consultation with other jurisdictions, organizations, affected parties and others as outlined in SARA section 39. DFO prepared the 2016 recovery strategy (DFO 2016) in cooperation with the Province of B.C. DFO consulted extensively on the 2016 recovery strategy (details in appendix 1 of the 2016 recovery strategy).

Consultations on the 2016 recovery strategy occurred through posting the draft recovery strategy online for comments, workshops and community open houses. Letters containing the consultation weblink and offering the opportunity for bilateral meetings or participation in workshops were sent to 29 Indigenous Organizations. Four First Nations representatives participated in workshops but no other responses to letters were received. Invitations to four workshops held in January and February 2011 were distributed by email to representatives from municipalities, regional districts, provincial ministries, federal agencies, industry, agriculture, environmental non-governmental organizations and stewardship groups. Input from 88 workshop participants on the draft recovery strategy was collected.

Over 2400 letters containing the consultation weblink, information on community open houses and maps of proposed critical habitat areas were sent to private landowners whose properties contained or were adjacent to proposed critical habitat. Public notices advertising community meetings were also placed in five area newspapers in English and three area newspapers in French. Over 230 people attended community open houses held in Chilliwack, Harrison Hot Springs and Aldergrove. Comments were received at the open houses, and through online feedback forms, emails and letters submitted directly to DFO.

Key concerns raised by stakeholders were fears regarding the future impacts of the 2016 recovery strategy and proposed critical habitat on existing land use practices and private lands, drainage maintenance issues, questions around the value and importance of the Salish Sucker and comments on stakeholders’ relationships with DFO. Most comments related to issues beyond the scope of the 2016 recovery strategy, which was based on the best available scientific information as required under SARA.

The draft amended recovery strategy was circulated to Indigenous organizations, local, regional and provincial governments, academia, environmental non-government organizations, and industry for a 35-day external review in December 2017 and January 2018. Input from the Province of B.C., the B.C. Agriculture Council, and the City of Chilliwack was received during external review. Additional stakeholder, Indigenous Organizations and public input will be sought through the publication of the proposed document on the Species at Risk Public Registry for a 60-day public comment period from November 2019 to January 2020. No comments were received during this period.

Appendix C: threat assessment categories

Appendix D: population level threats analysis

Threats analyses for the 11 known populations of Salish Sucker in Canada are presented in the following tables. Analyses were done in accordance with the Guidance on Assessing Threats, Ecological Risk and Ecological Impacts for Species at Risk (DFO 2014). Rationale for ratings is presented in a separate document (Pearson 2017).

^q The specific assessment categories and associated rankings definitions are provided in Appendix C.

^r Likelihood of occurrence: probability of a specific threat occurring for a given population over 10 years or 3 generations, whichever is shorter.

^s Level of impact: the magnitude of the impact caused by a given threat, and the level to which it affects the survival or recovery of the population.

^t Causal certainty: the strength of evidence linking the threat to the survival and recovery of the population.

^u Population-level threat risk: the product of likelihood and level of impact as determined using a risk matrix approach

^v Population-level threat occurrence: the timing of occurrence of the threat and describes whether a threat is historical, current and/or anticipatory

^w Population-level threat frequency: the temporal extent of the threat over the next 10 years or 3 generations, whichever is shorter.

^x Population-level threat extent: the proportion of the population affected by the threat

Appendix E: critical habitat maps

Critical habitat maps for the 11 known populations of Salish Sucker in Canada are presented in the following figures. Critical habitat mapping is also available through DFO’s Aquatic species at risk map website and the Government of Canada’s Open Maps website.

Appendix F: geographic coordinates of critical habitat

_y Reach start point indicates the location of the beginning of the reach in question along the watercourse.

^z Reach end point indicates the location of the end of the reach in question along the watercourse.

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