9. CURRENT MANAGEMENT FRAMEWORK

The current management framework is outlined here as it applies to people and habitat management.

9.1 First Nations Interests

Shared stewardship of B.C.’s shared fisheries resource and support of the food, social, and ceremonial needs of First Nations are critical to the recognition of established First Nation rights and entitlements. For WCT management, this means a need to consult on management issues that may affect First Nations culture. At all times, First Nations will be appropriately consulted following, at a minimum, province-wide (Province of British Columbia 2010), and Ministerial guidelines for consultation. Effective delivery of this management plan depends on relationship building and engaging First Nations in all activities, such as habitat restoration, as there is always the potential for information sharing and cost effective implementation. In addition, the collection of traditional knowledge, as begun in Prince (2001), should continue and could help clarify baseline data on distribution, for example.

9.2 Habitat Management

The following legislative tools may protect various aspects of fish habitat within WCT range:

Long Description for Table 9

Table 9 is titled “Legislative tools that may protect various aspects of fish habitat within WCT range.” The table is read horizontally from left to right, and consists of two columns and 13 rows. The top row contains the column headings: Legislation and Details. Horizontal headers titled “Federal” and “Provincial” further sub-divide the rows beneath it.

Table 9. Legislative tools that may protect various aspects of fish habitat within WCT range
LegislationDetails
Federal
Fisheries ActThe Fisheries Protection and Pollution Prevention provisions of the Fisheries Act provide protection to WCT.
Canada National Parks ActEnables the Governor in Council or the Minister responsible for the Parks Canada Agency to make regulations regarding management of parks including flora, fauna, and fisheries.
Species at Risk Act (SARA)One goal of SARA is to manage species of special concern to prevent them from becoming endangered or threatened. SARA requires the development and subsequent reporting on implementation of a management plan which includes measures for the conservation of the species. If a project is subject to an assessment under the Canadian Environmental Assessment Act 2012, measures must be taken to avoid or lessen any adverse effects of the project on the species.
Provincial
B.C. Wildlife ActWildlife Management Areas (not used for fish in general, but may provide indirect benefits.
Forest and Range Practices Act (FRPA)Identified Wildlife Management Strategy – WCT is on the schedule of species at risk that may be affected by forest and range practices and may require additional protection measures. An account for WCT lays out habitat needs and sensitivities, as well as appropriate measures for protection. Fisheries Sensitive Streams can also be designated under FRPA where fish values are high and sensitive to forest and range practices. To date, a single WCT stream, Palliser Creek, has been designated, indicating it requires special management to maintain key stream characteristics. Under FRPA, temperature-sensitive streams may also be designated to highlight the need to maintain water temperatures but to date no streams have been designated and no official procedure is in place to do so (L. Reese-Hansen, pers. comm., 2010). Wildlife Habitat Areas (only been used for Bull Trout so far) are another possibility.
Protected Areas relatedPark Act, Ecological Reserve Act, Reserve Act, Environment, Land Use Act – general intent is to maintain intact ecosystems
B.C. Fish Protection ActRiparian Areas Regulation – RAR only applies to local governments within the regional districts of Columbia/Shuswap and Thompson/Nicola. Both of these regions lie in the peripheral areas of the WCT range in B.C.
B.C. Water ActWater Act Modernization (in progress), the new proposed Water Sustainability Act and Living Water Smart program. Section 9 regarding “changes in and about a stream” – incorporating stream health and instream flow needs into water allocations.
B.C. Environmental Management ActCame into force in 2004 – especially Waste Discharge Regulation

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9.3 Fisheries Management

9.3.1 Regulatory Framework

Both federal and provincial legislation provides a framework for managing WCT fisheries:

  • Federal Fisheries Act – B.C. Sport Fishing Regulations (aggregate daily quota of 6 for CT) – regulates provincial quotas for all sport species
  • Provincial Wildlife Act – responsible for regulation of sport fish licenses for freshwater sport species
  • Canada National Parks Act and National Parks of Canada Fishing Regulations

9.3.2 Regional WCT Regulations

Increasingly conservative regulations have been put in place to improve angling quality in East Kootenay streams since the 1980s, in response to complaints over declines in abundance and fish size. In particular, these regulations have been geared to restoring a balanced age structure in WCT and reducing harvest (Oliver 2009). To this end, management has been effective in achieving these goals at least in the heavily angled waters of the Elk and St. Mary’s rivers. Seasonal angler catch has increased by 30-fold, WCT now make up 95% of the total catch, CPUEs have increased significantly (up to 3.5 times), and large fish (> 30 cm) are much more common (Oliver 2009). In addition, guided angling has increased significantly.

Furthermore, the East Kootenay Angling Management Plan (EKAMP) was completed in 2006 (B.C. Ministry of Environment 2006) as a response to overcrowding issues on what were considered premier WCT streams. Implicit in the EKAMP is that conservation needs have already been met.

The current angling regulations include (from 2009 to 2011 Freshwater Fishing Regulations Synopsis):

  • designation of Classified Waters (Class II) – Seven watersheds (including tributaries) have been classified including the Wigwam, Elk, Bull, St. Mary, and White rivers; Skookumchuck Creek; and Kootenay River upstream of White River confluence. All require purchase of a supplemental Classified Waters License.
  • single barbless hook on all East Kootenay waters
  • catch and release only on all streams from Nov. 1 to March 31; may apply year round to some WCT rivers such as catch and release only zones on several sections of the Elk River
  • no fishing on any streams from April 1 to June 14
  • daily catch quota is 5, but only 2 from streams and no more than 1 > 50 cm; may be more restrictive on some rivers (or some zones within rivers) where catch is reduced to one or zero fish
  • bait ban on many WCT rivers

9.3.3 Quality Waters Strategy

As previously discussed, the EKAMP lays out specific angler day quotas and guide number caps for each of seven Quality Waters streams. While these Quality Waters include all species, wild WCT is generally the targeted species by guided and non-guided anglers alike, although Bull Trout may also be targeted in the Wigwam River, and is a close “second” target in some other rivers (J. Burrows, pers. comm., 2011). The implementation of the River Guardians Program as part of the Quality Waters Strategy occurred to monitor status of the WCT fishing quality.

9.3.4 Fisheries Enhancement

Enhancement for recreational opportunities associated with WCT is currently limited to stocking of diploid F1 hatchery fish, fish originating from Connor Lakes broodstock. WCT stocking is now limited to mainly lakes, all within the native range of WCT. It remains unclear as to whether stocking occurs in systems with wild populations of WCT. Egg collections from wild broodstock in Connor Lake occur every 2 years. The Columbia Basin Fish and Wildlife Compensation Program may be initiating enhancement on some streams in the next 5 years.

9.3.5 Safeguarding/Refugia

No framework or policy is in place regarding the identification or creation of refuge populations of pure WCT but some have been considered recently including fishing closures, designation of headwater populations above barriers (COSEWIC 2006), and translocations to isolated areas above barrier locations. For example, a transplant from Cupola Creek to previously fishless Ventigo Creek has been initiated as part of an IPP project to provide an insurance population. While refugia can contribute to conservation goals, a full evaluation of effectiveness and potential impacts on other species needs to be considered in advance, in consideration of emerging policy and new biological/genetic information.

9.3.6 Provincial Parks

The Fish Stocking in Provincial Protected Areas Guideline is available for Protected Areas in B.C. However, Whiteswan Lake in Whiteswan Provincial Park represents a particularly challenging situation. The park was designated as a Class A park in 1978 (D. Biffard, pers. comm., 2011). The lake supports a regionally significant sport fishery and has been stocked regularly with Rainbow Trout from various strains from 1964 to 2009 (most recently Gerrard). Historically, stocking may have occurred as early as 1931 to 1957 but the lake was treated with toxaphene at this time to eliminate native non-sport species (J. Burrows, pers. comm., 2011). Diploid fish (1.5 million Rainbow Trout from various strains) were stocked up to 2003. A naturalized Rainbow Trout population became established in the lake and efforts were shifted to encourage natural spawning; such efforts included beaver control to maintain stream access. Most recently, native species control and enhancement of an invasive species were determined to be inconsistent with the Conservation Program Policy under the Park Act but permissible if expressly approved by the Regional Manager of Parks and Protected Areas. Currently, the Regional Manager approves a strategy to discontinue beaver control, monitor angler use, and stock to maintain the fishery with sterile Rainbow Trout (D. Biffard, pers. comm., 2011), but enhancement of spawning habitats has been discontinued since 2009. However, the situation remains challenging as rainbow are continuing to migrate out of the lake despite attempted containment with a barrier fences (Heidt 2007, 2009), and other preventative measures. Spawning rainbow are regularly found downstream of the lake and falls (Bell and Chirico (2007), as have numerous WCT hybrids (Rubidge and Taylor 2004, 2005).

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9.3.7 National Parks

Angling in the mountain national parks is managed through the Canada National Parks Act and the National Parks of Canada Fishing Regulations. In addition to the act and fishing regulations, Superintendent’s Orders at each park can be used for short-term management or to bridge the times between regulatory amendments. WCT have zero possession limits in Yoho and Kootenay. Streams and rivers are closed to angling in Mount Revelstoke and Glacier. Beyond this there is little information available for fisheries. They support very few anglers, waters tend to be fairly unproductive, and no enhancement or fertilization has been conducted since the 1970s. Regardless, the Eastern Brook Trout originally stocked throughout much of Kootenay and Yoho National Parks have now become the dominant species (S. Humphries, pers. comm., 2011).

9.4 Recommended Management Actions and Priorities

Recommended management actions for WCT in B.C. ensure that the Management Objectives (see Section 6) can be met, are intended to be consistent with the B.C. Freshwater Fisheries Program Plan goals (B.C. Ministry of Environment 2007), and return the species’ conservation status to not at risk. As evidence is unclear or lacking in many cases, actions are included as necessary to address key gaps in information, to address priority threats, and to directly address targets and objectives.

The full list of recommended actions is summarized in Table 10. Actions were prioritized according to immediacy of need. Actions that should be initiated immediately are noted as Essential. Most of these actions consist of inventory and monitoring, or habitat restoration and protection focused activities. This focus emphasizes the current lack of information available to describe population structure and distribution, as well as highlights the need for some immediate policy and planning to improve protection of WCT populations.

Recommendations for management on a provincial scale that can be used by government, partners, and interest groups to aid in determining resource priorities and to develop appropriate policy statements are summarized in the following sections.

Long Description for Table 10

Table 10 is titled “Summary of recommended actions considered critical in implementing the WCT management plan.” The table is read horizontally from left to right, and consists of three columns and 46 rows. The top row contains the column headings: Recommended Actions, Objective and Concern Addressed, and Priority. Horizontal headers titled “Population Conservation,” and “Habitat Protection/Restoration” further sub-divide the rows beneath it. Footnotes on the column headers “Objective and Concern Addressed” and “Priority,” and the table caption offer further explanation.

Table 10. Summary of recommended actions22 considered critical in implementing the WCT management plan.
Recommended ActionsObjectives and Concern AddressedPriorityt
Population Conservation

Define populations using predictive model:

  • Confirm status in unknown areas including peripheral areas
  • Consider data on range of movement, barrier data, hydrological units, genetics, threats, stocking records
  • Ground-truth species composition, logical hydrological units, genetics, demography, barrier surveys, habitat disturbances using standardized approaches
1; Knowledge GapEssential
Describe genetic structure of B.C. WCT populations.1; Knowledge GapBeneficial

Establish status of introgression in WCT populations:

  • Complete a genetic inventory update and gap analysis
  • Where hybridization is occurring, determine direction and rate of change
1; Knowledge GapEssential
Identify naturalized Rainbow Trout spawning locations focusing on locations where they are likely to concentrate (e.g., in lower elevation creeks), prioritize areas where there is potential cross-breeding with WCT.1; Threat: IntrogressionEssential
Identify naturalized Eastern Brook Trout populations.1; Threats: Altered Community DynamicsNecessary
Monitor upstream movement of U.S. hybrids within Flathead Population Group.1; Threats: IntrogressionNecessary
Determine if kokanee enhancement in Kookanusa could be a detriment to WCT production.1; Threats: Altered community dynamicsBeneficial
Define “pure WCT population” and establish thresholds to trigger appropriate management responses.1; Threats: IntrogressionNecessary
Prioritize WCT populations for restoration action based on genetic purity.1; Threats: AllNecessary
Gather aboriginal traditional knowledge, and other historic accounts of occurrence and unique characteristics to help clarify historical distribution, relative abundance, and fish community structure1, 2; Knowledge GapNecessary

Develop policy and regulations for protection and restoration of wild WCT populations including consideration of:

  • Regulations: opportunistic removal in areas of high hybridization and naturalize Rainbow Trout populations (listed in Appendix 4)
  • Policies: refugium/transplantation; barrier use; nutrient supplementation; and hatchery supplementation. Note that B.C. currently does not use hatchery supplementation to restore salmonid populations thus it would first have to be considered in an experimental/evaluation context (Province of British Columbia 2005).
  • “Habitat banking” – explore as a compensation option and determine if/when using this might be appropriate.
1; Threats: Introgression; Fish passage; large-scale habitat modificationsEssential

Review recreational stocking programs for WCT, Rainbow Trout, and Eastern Brook Trout to ensure risks to WCT are minimized:

  • WCT stocking in Connor Lake – review stocking plan to ensure no stocking into wild WCT waters
  • Eastern Brook Trout stocking – confirm plan meets current stocking policy
  • Rainbow Trout stocking – confirm all current stocking in WCT range is in isolated lakes and uses sterile fish; reduce Rainbow Trout stocking in key WCT range and consider stocking with native species as an alternative
1; Threat: IntrogressionNecessary

Support stewardship initiatives by local governments, angling groups, and stream stewardship groups, by helping prepare the following for a wider distribution than the regulations synopsis:

  • species identification tools;
  • education material to reduce hooking injury mortality;
  • education materials for schools/angling clubs on biology, threats (especially invasive species and introgression), such as brochures, Powerpoint presentations, and relevant signage; and
  • promote stewardship agreements/conservation covenants.
1-4; allBeneficial
Develop Whiteswan Lake management plan for WCT due to confirmed hybrid status (WCT x RBT) in watershed. Plan should include stocking recommendations, naturalized Rainbow Trout population management, barrier use, etc.1, 2; Threats: IntrogressionEssential
For wild, unexploited WCT populations, use threat analysis to identify at risk populations and assess carrying capacity of a random subset of these populations.1, 2; Knowledge GapBeneficial

Identify wild, exploited stream and lake WCT populations (include subgroups if necessary) for individual stock assessment including Classified Waters and non-Classified Waters:

  • Classified Waters: Bull, Wigwam, Elk, St. Mary, Skookumchuck, White, and Upper Kootenay rivers
  • Non-Classified Waters: Flathead, Akolkolex, Goat, Findlay, and Lussier rivers
  • Other small populations
2; Knowledge GapEssential

Develop a measure of carrying capacity for each exploited WCT population using:

  • the empirical approach (preferred) on as many populations as possible to measure total abundance and harvest rate; or
  • the modeling approach (as needed) which requires considerable demographic information.
2; Knowledge GapNecessary

Develop and implement standard protocols to determine WCT total abundance.

  • Consider the following methods:
    • Snorkeling – adult count of entire river
    • Mark recapture – watershed or reach scale
    • Catch per unit effort (could be hyper-stable, needs investigation before use)
    • Genetic analysis (needs investigation to determine if plausible).
  • Determine fry/parr densities (e.g., night-time snorkeling).
  • Determine if the different methods produce equivalent results.
  • Document, test, and prioritize each protocol.
  • Develop long-term sampling strategy to obtain data for carrying capacity.
2; Knowledge GapEssential
Establish a periodic schedule of WCT stock re-assessments that is prioritized around relative threat risk and availability of occurrences.2; Knowledge GapNecessary
Determine if a single Nequilibrium value for large, productive systems and its associated WCT Objective 2 target is appropriate given variability in productivity observed even among Classified Waters rivers.2; Knowledge GapNecessary
Based on application of abundance-related reference points, develop a summary of WCT manage actions for each management zone (as adapted from Johnston et al. 2002).2; Knowledge GapNecessary
For wild, unexploited WCT populations manage threats to keep populations above the Limit Reference Point (0.2 equilibrium or higher in very small populations).2; Threats: AllBeneficial
Determine if the “persistence” goal for wild, unexploited (headwater) WCT populations of 0.2·Nequilibrium (Limit Reference Point) needs adjusting (may not be high enough). Adjust as needed.2; Knowledge GapNecessary
Determine how to assess angling mortality, and obtain direct measures of catch and release mortality for each fishery (e.g., fly fishing only in catch and release zone, gear in catch and release zone, fly fishing in kill zone, gear in kill zone).2; Knowledge Gap;
Threat: Direct mortality
Necessary
Evaluate physiological impacts of catch and release: condition factor, age at size, post-release mortality (24- to 48-hr mortality standard).2; Knowledge Gap; Threat: Direct mortalityNecessary
Habitat Protection/Restoration
Identify key habitats for migratory and resident WCT populations.3; Knowledge GapNecessary
Review fish barrier information and further investigate to confirm significance of threat (e.g., reduction in carrying capacity) to WCT.3; Threats: Fish passage; Small-scale habitat modificationsEssential

Support Water Act modernization including:

  • establishing fish flow needs for WCT and identify priority watersheds with persistent deficiencies,
  • strengthen provisions regarding release of damaging substances to high risk streams, and
  • support/develop water management plans in priority streams.
3; Knowledge Gap; Threat: Altered flow regimeBeneficial
Explore the possibility of extending Riparian Area Regulations in Kootenays beyond Revelstoke, toward the goal of identify opportunities for regulating minimum riparian protection widths in areas of the province where they do not currently exist.3; Threats: Small/large-scale habitat modificationsBeneficial
Complete stream restoration activities in streams with identified habitat deficiencies, impacts, or high fishing pressures1-4; all; Threats: riparian alteration, altered flow regimes, instream habitat modificationsEssential
Sustainable And Diverse Recreational Opportunities
Obtain use information for priority non-Classified Waters: Goat, Lussier, Findlay, and Wildhorse rivers.4; Knowledge GapBeneficial
Determine linkage between catch per unit effort and fish abundance.2, 4; Knowledge GapNecessary
Determine advantage of a catch per unit effort target for Classified Waters.4; Knowledge GapBeneficial
Determine if commercial activities are adequately regulated on non-Classified Waters.4; Knowledge GapNecessary
Determine benefits of small lakes recreation associated with WCT and consider ways to optimize sustainable recreation including stocking, lake enrichment, etc.4; Knowledge GapBeneficial
Determine information needed to better understand and define WCT harvest opportunities. Develop a plan to explore potential harvest opportunities.4; Knowledge GapBeneficial
Expand the River Guardian program to priority non-Classified Waters, including data gathering on compliance monitoring (including small streams), and harvest rate determination.4; Threats: severalBeneficial
Consider Skeena approach (Dolan 2008) to deal with oversubscription issues for Wigwam River and Elk River.4; Threat: Direct mortalityNecessary
Advertise WCT status via appropriate bulletin/poster program to educate public on its conservation status and required management.1, 2, 3, 4;
Threats: several
Beneficial

s Objectives are described in Section 6.

t Essential (urgent and important, needs to start immediately); Necessary (important but not urgent, action can start in 2–5 years); or Beneficial (action is beneficial and could start at any time that was feasible).

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9.4.1 Population Conservation (Objectives 1 and 2)

Population protection and recovery for WCT are the top priorities for this management plan; conservation is also the foundation upon which a sustainable recreational fishery can be maintained. To date, the conservation of wild WCT populations has been mainly ad hoc and reactive, in response to declining angling quality, with a few one-off initiatives such as translocations associated with water and land use. Angling regulations have become increasingly restrictive resulting in a positive response in terms of more, larger fish observed in the few rivers tracked. Introgression and altered communities associated with past stocking initiatives have only been recently considered in stocking changes; specifically limiting stocking to sterile Rainbow Trout (3N RBT) in the East Kootenays and sterile (all female) Eastern Brook Trout (AF3N EBT) province wide (see FFSBC 2003 for a detailed description of stocked fishes). The extent to which hybridization exists and is ongoing remains unknown but potential for impact appears greatest in Upper Kootenay and Elk Population Groups. Furthermore, reference points for population abundance have not been determined and it is unclear if angling-related mortality is a significant issue in any of the fisheries (e.g., Classified Waters, non- Classified Waters summer, non- Classified Waters winter).

9.4.2 Habitat Protection/Restoration (Objective 3)

Habitat protection and restoration are fundamental components of conservation. Few landscape-level assessments have considered habitat availability and quality specifically for WCT in B.C., although several location-specific assessments have been conducted. Forestry-related concerns are thought to be mainly residual (i.e., from pre-Forest Practices Code days) although some concerns exist under the current results-based framework and require increased compliance monitoring on behalf of government and industry. Agricultural and urban development, mainly related to riparian issues and water diversions, need to ensure WCT needs are met. Furthermore, the extent that stream crossings represent a significant barrier to upstream habitats needs to be determined. Finally, water quality concerns related to coal mining are significant in the Elk Population Group and need to be monitored.

9.4.3 Sustainable and Diverse Recreational Opportunities (Objective 4)

Assuming conservation needs are met, the provision of recreational opportunities is fundamental to the Fisheries Program. Fisheries for WCT in B.C. have become increasingly conservative since the 1980s. At least in Quality Waters, the response is generally positive with quality of angling experience considered very good to high. However, overcrowding is becoming a greater issue on some streams, and compliance is a concern for both Classified and Non-classified Waters. The extent to which harvest can be maintained is not known. Similarly, there may be additional opportunities on small lakes of which we are currently unaware. Actions to be taken include exploring additional potential recreational fishing opportunities and working within the AMP process for Quality Waters to ensure that high quality opportunities are maintained. The WCT Management Plan defines WCT usable surplus; this surplus (i.e., harvest opportunities) will be addressed via an independent regulation setting process.

9.4.4 Recommended Approach

A number of initiatives and projects were recommended to provide protective measures and address key knowledge gaps for WCT (Table 10). One of the highest priority items involves defining populations and prioritizing them for conservation. It is recommended that this be undertaken at the population level as watershed-level evaluation is considered to be too coarse a filter. To do this, discrete populations will need to be identified and their abundance level and associated management approach determined (see Appendix 2). It will take significant resources to undertake a predictive modeling exercise to spatially define all populations across the landscape. However, exploited populations are readily identified, and status can be in part assessed using stock assessment tools to evaluate abundance. Angling activity will need to be taken into account as angling pressures are increasing (along with improved harvest and compliance monitoring and fishing regulation assessments). Once populations have been assessed, a methodology to prioritize conservation efforts will need to be identified and applied.

Thus, in terms of activities that can be undertaken immediately, two high priority activity areas are apparent. First, a comprehensive stock assessment plan that establishes standardized methodologies to evaluate abundance in exploited systems should be initiated as soon as possible. This approach will not only evaluate existing and new methodologies available to estimate abundance and track trends, but will also identify priority populations for trend assessment. Such a plan will enable limited resources to be appropriately allocated. Second, in terms of protective and restoration measures to address hybridization, few additional resources are required to develop two policy-related pieces: a broader piece regarding barriers- and the Swan Lake Management Plan. As well, the development of a regulatory strategy to address Rainbow Trout presence where they co-occur with WCT should be initiated.

9.5 Management Plan Updates and Implementation Monitoring

The long time span required to document population recovery and ongoing management required for exploited populations necessitates a management plan that evolves over time. There are continuing advances in our understanding of the biology of native WCT (e.g., life history determination, population biology and genetics), stock assessment methodology and results, in addition to changes in the interest and concerns of anglers, First Nations and the general public. The landscape also changes, with rapidly developing anthropogenic changes altering the threats to the species, and the structure, jurisdictions, and capacity of management agencies are in a period of uncertainty and great flux. An effective management plan must be informed by these changes and the management objectives and priorities evolve to reflect them. To be current and effective this plan should be evaluated every 5 years and updated as necessary (a SARA requirement). The goal is to provide at least one up-to-date version to inform each COSEWIC reassessment, which currently occurs approximately every 10 years (next 2016).

The Essential activities prioritized in Table 10 should be completed over the next 5–10 years, and can serve as benchmarks and performance measures to evaluate progress towards meeting the Plan objectives. These activities directly relate to the COSEWIC reasons for designation (i.e., hybridization and competition with introduced species, development, agricultural, and resource-based industries), and provide the stock assessment information necessary to evaluate progress toward conservation and recreation objectives.

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10. Effects on Other Species

Implementation of actions consistent with the objectives in this plan is intended to prevent WCT from becoming further at-risk and return the species’ conservation status to “not at risk,” and meet our global responsibility for the species’ conservation. Additional outcomes of actions to maintain or improve the capacity of natural habitats and ecosystem function will benefit many other fish, mammal, and bird species. Several potentially affected SARA-listed aquatic species include Umatilla Dace (Rhinichthys umatilla), Shorthead (Cottus confuses) and Columbia (Cottus hubbsi) sculpins, Painted Turtle (Chrysemys picta), Rocky Mountain Tailed Frog (Ascaphus montanus), White Sturgeon (Acipenser transmontanus), and Bull Trout. The potential for the plan to inadvertently lead to effects on other species was considered. This plan will clearly benefit the environment and will not entail any significant adverse effects.

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Personal Communications

  • Doug Biffard. Aquatic Ecologist, Parks and Protected Areas, B.C. Ministry of Environment, Victoria, BC. January 2011.
  • Jeff Burrows. Senior Fish Biologist, B.C. Ministry of Forests, Lands and Natural Resource Operations, Nelson, BC. January 2011.
  • Peter Corbett. Mirkwood Ecological Consultants Ltd, Winlaw, BC. December 2010.
  • Kevin Heidt. Fisheries Technician. B.C. Ministry of Forests, Lands and Natural Resource Operations, Cranbrook, BC. December 2011.
  • Shelley Humphries. Parks Canada Aquatics Specialist, Lake Louise, Yoho and Kootenay National Parks. December 2010.
  • Cory Legebokow. Ecosystems Specialist. B.C. Ministry of Environment, Revelstoke, BC. December 2010.
  • Doug Martin. Senior Ecosystem Specialist, B.C. Ministry of Environment, Cranbrook, BC. Email correspondence. January 2011.
  • Craig Mount. Aquatic Habitat Geomorphologist, B.C. Ministry of Environment, Victoria, BC. January 2011.
  • Ron Ptolemy. Instream Flow Specialist, B.C. Ministry of Environment, Victoria, BC. December 2010.
  • Lars Reese-Hansen. Ecosystem Planning Biologist, B.C. Ministry of Natural Resource Operations, Victoria, BC. January 2010.
  • Mike Robinson. Independent Consultant, Cranbrook, BC. December 2010.
  • Dr. Eric Taylor. Professor, Department of Zoology, University of British Columbia, Vancouver, BC. November 2010.
  • Byron Woods. GIS Coordinator, B.C. Ministry of Environment, Victoria, BC. Ongoing.

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APPENDIX 1. HABITAT USE IN THE ELK RIVER

The following summary describes more specifically habitat use by WCT in the Elk River; this information is useful in understanding the need for intact migration routes, as well as the extent to which WCT use different habitats at different times. This recent radio-tagging study on the Elk River conducted in 2001–2002 identified important habitats for WCT (Westslope Fisheries Ltd. 2003).

Overwintering habitat was characterized by deeper river sections with glides and pools, in both iced over and open sections of river. Fish tended to aggregate in these sections starting in October, where they remained until the following April. Most notably, the fish in the upper sections migrated twice the distance that fish in the lower sections of the Elk River did to access overwintering sites, namely the Elk Lakes. Once there, the fish remained fairly sedentary. Elk Lakes are undoubtedly one of the few areas in the headwater section of the watershed with adequate depth to support adult WCT during the winter. In the lower river sections, fish tended to move frequently throughout the winter, possibly to avoid ice movement. Fish moved both upstream and downstream to access overwintering habitat in this lower section. The longest distance traveled between spawning and overwintering habitats during the study was 60 km.

Spawning habitat was documented in both tributaries and mainstem areas where gravels have been freshly deposited post-freshet. Tributary spawners in the lower Elk River exhibited the longest migrations to spawning grounds of up to 20 km. Although macro-habitats selected for spawning varied from main channel margins to side channels and perennial creeks, the specific characteristics were fairly similar among them. Redds tended to be clumped, and found in areas with an abundance of large woody debris and undercut banks. The dominant substrate used was gravel (1.8–3.3 cm diameter). Spawning occurred in late May and June when temperatures reached 7–11oC, but specific timing depended on elevation and snow pack runoff.

Conclusions from this study indicate for WCT in the Elk River:

  1. A range of overwintering and spawning migrations (extensive vs. short distances) is observed, reflecting different life histories and habitat availability.
  2. Spawning habitats include a range of locations (mainstem margin, offchannel, ephemeral, and perennial tributaries). While most fish spawned in the mainstem, some spawned in Morrissey, Lizard, Hartley, Michel, and Fording creeks, as well as the outlet of lower Elk Lake.
  3. Spawn time appeared to be linked to key stream conditions including temperature and flow (downward limb of hydrograph after fresh gravels are deposited).
  4. Microhabitat selection appears to be fairly invariable, regardless of location.

APPENDIX 2. DETAILED DESCRIPTION OF FRAMEWORK AND DERIVATION OF ABUNDANCE TARGETS (TO MEET OBJECTIVE 2)

Objective 2. Maintain wild populations at abundance levels that prevent at-risk status assessment so that the populations can provide sustainable societal benefits

Management framework
The three abundance thresholds are illustrated in Figure A2.1. The framework assumes that managers can alter either mortality rates or stock productivity through management actions. For populations that support recreational fisheries, the management actions will often be changes in fishing mortality rates.

Figure A2.1. The elements of an abundance-based precautionary management framework. Three abundance thresholds (the limit reference point, LRP; the conservation concern threshold, CCT; and the target reference point, TRP) force mandatory changes in management actions that are intended to maintain a population within the routine management zone, where sustainable societal benefits are optimized. Within the conservation concern and extreme conservation concern zones of abundance, management actions are increasingly directed towards promoting population recovery (e.g., by reducing harvest rates from HTR to HLR), and potential societal benefits are correspondingly reduced. Population abundance is measured relative to the asymptotic maximum abundance (see below).

Long Description for Figure A2.1

Figure A2.1 is titled “The elements of an abundance-based precautionary management framework. Three abundance thresholds (the limit reference point, LRP; the conservation concern threshold, CCT; and the target reference point, TRP) force mandatory changes in management actions that are intended to maintain a population within the routine management zone, where sustainable societal benefits are optimized. Within the conservation concern and extreme conservation concern zones of abundance, management actions are increasingly directed towards promoting population recovery (e.g., by reducing harvest rates from HTR to HLR), and potential societal benefits are correspondingly reduced. Population abundance is measured relative to the asymptotic maximum abundance (see below).” The x-axis is labelled as “Relative abundance” and ranges from 0.0 to 0.5. The y-axis is labelled as “Management action” and ranges from 0.0 to 0.6. The graph is divided by three vertical dashed lines: the limit reference point (LRP, at 0.15 on the x-axis), the conservation concern threshold (CCT, at 0.3 on the x-axis), and the target reference point (TRP, at 0.45 on the x-axis). These define the boundaries of three zones: to the left of the LRP is the extreme conservation concern zone; in-between the LRP and CCT is the conservation concern zone; and, to the right of the CCT is the routine management zone. On the bottom right corner of the graph (0.5, 0.0), the Harvest Limit Reference is labelled as HLR. A dashed line on the graph begins at coordinates (0.15, 0.0), extending with a positive linear slope to coordinates (0.3, 0.4) at which point the line extends horizontally to (0.5, 0.4); this point is labelled as HTR, the Harvest Target Reference.

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The key abundance threshold is the “conservation concern threshold” (CCT on Figure A2.1). The CCT identifies an abundance level below which the ability of the population to provide sustainable benefits is reduced and the likelihood of long-term decline is increased. The conservation concern threshold is used as a precautionary threshold to force mandatory management actions (such as reductions in harvest rates or other anthropogenic sources of mortality) that are intended to arrest population declines and return populations to desired abundance levels quickly under average environmental conditions. The intensity of management actions increases as the difference between current abundance and the conservation concern threshold increases. For example, permitted fishing mortality rates would be decreased at lower population abundance (Figure A2.1). A population whose abundance is below the conservation concern threshold may still be capable of providing sustainable societal benefits such as fish harvest, but at a reduced level. Operationally, we define the conservation concern threshold to be the adult abundance at maximum sustainable yield, NMSY, below which a population is considered to be overfished. This usage conforms to the FAO Code of Conduct for Responsible Fisheries, which considers a minimum management objective to be to “maintain or restore stocks at levels capable of producing maximum sustainable yield.”

The limit reference point (LRP on Figure 1) marks an abundance level below which the risk of non-recovery to the routine management zone within a predetermined time under average environmental conditions is deemed to be unacceptable. As abundance declines below the LRP, the long-term viability of the population and its ability to provide desired societal benefits in the future are increasingly threatened. For small populations, the risk of extinction will increase greatly at abundances below the LRP. The LRP is intended to force management actions to restore a depressed population before population viability is imperiled. Management actions could include extraordinary measures such as the elimination of all anthropogenic sources of mortality, the reduction of controllable sources of natural mortality, and measures to increase stock productivity. Operationally, we define the LRP for moderately productive salmonid populations such as WCT to be the abundance from which a population is expected to recover to the conservation concern threshold within 1–2 generations under average environmental conditions. Simulations of the dynamics of a well-studied steelhead population indicate that this definition will usually avoid extirpation for small stocks when combined with mortality reductions (Johnston et al. 2000). Because the rate of recovery of a depressed population depends on stock productivity, which is usually known imprecisely, it is desirable to define the LRP such that it remains effective despite this uncertainty.

Abundance levels above the conservation concern threshold define a “routine management zone” (Figure A2.1) where the risk of an irreversible decline in abundance is low and the population can be managed to optimize societal benefits. The target reference point (TRP in Figure A2.1) is the abundance level at which the chosen measure of societal benefit is maximized. The location of the TRP will vary with the management objectives for the stock and with the factors that are included in the metric of societal benefit that is to be maximized. Stakeholder consultations may help define the factors to be considered. For harvest fisheries, the TRP may be close to NMSY to maximize yields, whereas for catch and release fisheries the TRP may be close to the unfished equilibrium abundance to maximize expected catch rates. Specific analyses to determine the TRP may be required if economic criteria or other non-fishery measures of societal benefit are to be considered, but in no circumstances will the TRP be permitted to be below the conservation concern threshold.

Abundance thresholds and benchmarks for WCT
Defining management reference points for WCT and other species that may exist as numerous small, discrete populations is difficult because normally there is little or no quantitative abundance information available for a given population. In particular, there are few data on stock productivity, which determines the rate of recovery at low abundance. Even where reliable data exist, estimates of the parameters that are needed to establish reference points can be very imprecise. Establishing effective limit reference points is particularly important, however, because the small size of many populations increases their vulnerability to extirpation. Because of the data limitations, effective reference points that do not require stock productivity information are desirable. Our approach is to use a simple analytical method to determine limit reference points and conservation concern thresholds. The method is appropriate for demographically independent populations of territorial, stream-rearing salmonids whose stock-recruit relationships often approximate a Beverton-Holt model (Figure A2.2). Although there are other alternatives, this model is reasonable and gives thresholds that can be estimated from limited abundance data for unexploited populations. For a Beverton-Holt stock-recruit relationship, the CCT (defined to be NMSY) is:

CCT = NMSY = B · a-0.5 – B · a-1

(Johnston et al. 2002).

Figure A2.2. A Beverton-Holt stock-recruitment relationship (blue line): Recruits = a·Spawners / ( 1 + a·Spawners / B), where a is the stock productivity and B is the asymptotic maximum abundance. Stock productivity is the rate of population increase at very low abundance (diagonal dashed line, labelled “a”). The asymptotic maximum abundance, B, is the expected recruitment at very high spawner abundance; it is estimated from a time-series of spawner-recruit data. An unfished population will fluctuate about the equilibrium population size, Nequilibrium, which is always less than B for a Beverton-Holt model. The solid black line is the 1:1 line where recruits equal spawners. The difference between the 1:1 line and the stock-recruit relationship is the (potentially) harvestable surplus. NMSY is the spawner abundance which produces the largest harvestable surplus. In this example, a = 5, spawners and recruits are both given in units of B, NMSY = 0.247·B and Neq = 0.80·B.

Long Description for Figure A2.2

Figure A2.2 is titled “A Beverton-Holt stock-recruitment relationship (blue line): Recruits = a·Spawners / (1 + a·Spawners / B), where a is the stock productivity and B is the asymptotic maximum abundance. Stock productivity is the rate of population increase at very low abundance (diagonal dashed line, labelled “a”). The asymptotic maximum abundance, B, is the expected recruitment at very high spawner abundance; it is estimated from a time-series of spawner-recruit data. An unfished population will fluctuate about the equilibrium population size, Nequilibrium, which is always less than B for a Beverton-Holt model. The solid black line is the 1:1 line where recruits equal spawners. The difference between the 1:1 line and the stock-recruit relationship is the (potentially) harvestable surplus. NMSY is the spawner abundance which produces the largest harvestable surplus. In this example, a = 5, spawners and recruits are both given in units of B, NMSY = 0.247·B and Neq = 0.80·B.” The formula R = a·S / ( 1 + a·S / B ) is centered on top of the graph. The x axis is labelled as “Spawners” and ranges from 0.0 to 1.2. The y axis is labelled as “Recruiters” and ranges from 0.0 to 1.2. At 1.0 on the y-axis, a straight black dashed line labelled as “B” crosses the graph horizontally. Another black dashed line labelled as “a” begins at (0.0, 0.0) and extends with a positive linear slope to approximately (0.15, 0.75). A solid black diagonal line crosses the graph diagonally from (0.0, 0.0) to (1.2, 1.2). A solid blue line originating at (0.0, 0.0) curves upwards, crosses the solid diagonal black line at approximately (0.8, 0.75) (this blue point is labelled as Neq), and ends at approximately (1.2, 0.85). On the x-axis, a red point labelled NMSY is situated at approximately (0.25, 0.0). A vertical solid red line aligned with 0.25 on the y-axis connects the solid black diagonal line to the curved blue line.

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Although the conservation concern threshold depends on stock productivity, it is a slowly varying function of stock productivity within the range typically seen for salmonids, and has an upper bound of 0.25·B (Figure A2.3). While we lack estimates of stock productivity for most populations of WCT, we can nevertheless define the conservation concern threshold as 0.25·B (we will later modify this value slightly to account for environmental variability). This value will be a very good approximation to the exact value over the range of stock productivity that is likely for small populations of salmonids (Figure A2.3, left panel) and it will provide significant protection to populations with very low stock productivity, which is a desirable outcome for small populations that are especially vulnerable to extirpation. If the conservation concern threshold is defined as a constant proportion of the asymptotic maximum abundance, the limit reference point for one-generation return can easily be determined. The LRP is:
LRP = B · CCT / a · (B – CCT).

The limit reference point depends strongly on stock productivity but is bounded by 0.13·B for recovery to NMSY within one generation (Figure A2.3, left panel). Recovery to 0.25·B requires a slightly higher limit reference point at very low stock productivity (Figure A2.3, left panel).

Figure A2.3. Abundance-based management thresholds may vary with stock productivity. The spawner abundance at maximum sustainable yield (NMSY, solid green line) for a Beverton-Holt type stock-recruitment relationship (left panel) is a slowly-varying function of stock productivity that approximates (and is bounded by) 0.25·B (CCT, dashed black line) where B is the asymptotic maximum recruitment. The spawner abundances from which a stock can recover to NMSY (solid red line) or to 0.25·B (dashed red line) within one generation define possible limit reference points (LRP). For a Ricker-type stock-recruitment relationship, NMSY varies more strongly with stock productivity and is a greater proportion of the asymptotic maximum abundance than NMSY for a Beverton-Holt SRR with the same stock productivity. Nequilibrium (blue line) is the equilibrium abundance about which an unfished population will fluctuate.

Long Description for Figure A2.3

Figure A2.3 is titled “Abundance-based management thresholds may vary with stock productivity. The spawner abundance at maximum sustainable yield (NMSY, solid green line) for a Beverton-Holt type stock-recruitment relationship (left panel) is a slowly-varying function of stock productivity that approximates (and is bounded by) 0.25·B (CCT, dashed black line) where B is the asymptotic maximum recruitment. The spawner abundances from which a stock can recover to NMSY (solid red line) or to 0.25·B (dashed red line) within one generation define possible limit reference points (LRP). For a Ricker-type stock-recruitment relationship, NMSY varies more strongly with stock productivity and is a greater proportion of the asymptotic maximum abundance than NMSY for a Beverton-Holt SRR with the same stock productivity. Nequilibrium (blue line) is the equilibrium abundance about which an unfished population will fluctuate.” Two graphs are depicted. The x axis of both graphs is titled “Stock productivity (recruits spawner-1),” and spans from 1 to 10. The y axis of both graphs is titled “Spawner abundance (B-1),” and spans from 0.0 to 0.6. On both graphs, at approximately 0.25 on the y-axis, a black dashed line labelled as CCT crosses the graph horizontally. The graph on the left is titled “Beverton-Holt SRR.” A solid red line labelled as LRPNMSY begins at approximately (1.0, 0.02) on this graph, curves upwards, then descends, ending at approximately (10, 0.02). A red dashed line labelled as LRP0.25 B begins at approximately (1.0, 0.32), curves downwards, and ends at approximately (10.0, 0.02). A solid blue line, labelled as Nequil begins at approximately (1.0, 0.03) and curves steeply upwards, ending at approximately (2.4, 0.58). A solid green line labelled as NMSY begins at approximately (1.0, 0.03), touches the conservation concern threshold, and then curves downward, ending at approximately (10.0, 0.03). The graph on the right is titled “Ricker SSR.” A solid red line labelled as LRPNMSY begins at approximately (1.0, 0.06) on this graph, curves upward, and ends at approximately (10.0, 0.02). A red dashed line labelled as LRP0.25 B begins at approximately (1.2, 0.56), curves downward, and ends at approximately (10.0, 0.05). A solid blue line, labelled as Nequil begins at approximately (1.0, 0.13), extends steeply upward, and ends at approximately (1.3, 0.55). A solid green line labelled as NMSY begins at approximately (1.0, 0.13), curves upward, and then curves downward, ending at approximately (10.0, 0.21).

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In the absence of population-specific stock productivity information, defining management thresholds as fixed proportions of the asymptotic maximum abundance (e.g., LRP ≈ 0.13·B and CCT ≈ 0.25·B) is a justifiable approximation that will be operationally effective in many cases. There are two potential pitfalls inherent in this approach, however. The first is uncertainty about the “true” structural form of the stock-recruitment relationship. The management thresholds suggested for a Beverton-Holt type stock-recruitment relationship are apparently less effective for a Ricker model (Figure A2.3, right panel) or for a hockey-stick model (Johnston et al. 2002). The second pitfall is the fact that the asymptotic maximum abundance is not directly observable for a Beverton-Holt model; it is estimated from stock-recruitment analyses. Unexploited populations will fluctuate about their equilibrium abundances, which are considerably lower that the asymptotic maxima (Figure A2.2).

The potential management thresholds can be re-expressed as proportions of the observable equilibrium abundance (Figure A2.4). It is apparent that management thresholds for unproductive stocks must be large fractions of their equilibrium population sizes, e.g., CCT ≈ 0.4·Nequilibrium to 0.5·Nequilibrium and LRP ≈ 0.3·Nequilibrium to 0.4·Nequilibrium independent of the form of the stock-recruitment relationship. For moderately productive stocks, say a ≥ 3 recruits·spawner-1, CCT values should be roughly 0.35·Nequilibrium to 0.4·Nequilibrium and LRP ≈ 0.1·Nequilibrium to 0.2·Nequilibrium. In general, the effect of parameter uncertainty and environmental variability is to increase the required management thresholds, although this depends on the variance of the stochastic process error and the nature of the control rules applied between the conservation concern threshold and the limit reference point (Johnston et al. 2000); an example of the effectiveness of various LRP definitions in altering the risk of “extinction” is given in Figure A2.5. Unfortunately, we currently lack the demographic information to perform similar analyses for WCT. In the absence of stock productivity information, we propose that the conservation concern threshold should be assumed to be 0.4·Nequil and the limit reference point to be 0.2·Nequilibrium.

The equilibrium abundance from which population-specific management abundance thresholds can be established can be approximated as the average density measured for unexploited populations in undisturbed habitat or estimated from habitat capacity models. For a salmonid species whose life-history can be separated into a juvenile stage with density-dependent mortality and an older stage with density-independent mortality, the appropriate density for setting management thresholds must occur after the density-dependent stage, which is often the smolt stage. For WCT, the best current estimates of habitat capacity are likely the densities of catchable fish (i.e., those fish > 30 cm fork length) estimated from snorkel surveys on lightly fished populations (e.g., Oliver 1990) or on classified waters with mandatory catch and release regulations where fishing mortality may be low (e.g., Hagen and Baxter 2009). Data for the lower St. Mary River, a large and productive system, suggest an equilibrium abundance near 75 fish > 30 cm fork length per river km (Oliver 1990). Densities on other Classified Waters currently range from about 15 to 45 fish·km-1 (Hagen and Baxter 2009); however, it is not clear whether these values can be considered as estimates of the equilibrium densities of the various populations.

Figure A2.4. Management thresholds expressed in terms of the equilibrium abundance, Nequilibrium, for Beverton-Holt (left panel) and Ricker (right panel) stock-recruitment relationships. NMSY is the spawner abundance at maximum sustainable yield, CCT0.25B is 0.25 of the asymptotic maximum abundance, LRPNmsy is the abundance from which a population can recover to NMSY within one generation under average conditions, and LRP0.25B is the abundance from which a population can recover to 0.25 of the asymptotic maximum abundance within one generation under average conditions.

Long Description for Figure A2.4

Figure A2.4 is titled “Management thresholds expressed in terms of the equilibrium abundance, Nequilibrium, for Beverton-Holt (left panel) and Ricker (right panel) stock-recruitment relationships. NMSY is the spawner abundance at maximum sustainable yield, CCT0.25B is 0.25 of the asymptotic maximum abundance, LRPNMSY is the abundance from which a population can recover to NMSY within one generation under average conditions, and LRP0.25B is the abundance from which a population can recover to 0.25 of the asymptotic maximum abundance within one generation under average conditions.”Two graphs are depicted. The x-axis on both graphs is titled “Stock productivity (recruits spawner-1),” and spans from 1 to 10. The y-axis on both graphs is titled “Spawner abundance (N equil-1),” and spans from 0.0 to 0.6. . On both graphs, at 0.4 on the y-axis, a black dashed line crosses the graph horizontally. The graph on the left is titled “Beverton-Holt SRR.” A solid red line labelled LRPNMSY begins at approximately (1.0, 0.5) and curves downward, ending at approximately (10.0, 0.03). A red dashed line labelled as LRP0.25 B begins at approximately (1.6, 0.56) and curves downward, ending at approximately (10.0, 0.03). A green solid line labelled as CCT0.25B begins at approximately (1.8, 0.57) and curves downward, ending at approximately (10.0, 0.28). A blue solid line labelled NMSY begins at approximately (1.0, 0.5) and curves downward, ending at approximately (10.0, 0.24). The graph on the right is titled “Ricker SRR.” A solid red line labelled LRPNMSY begins at approximately (1.0, 0.5) on this graph and curves downward, ending at approximately (10.0, 0.03). A red dashed line labelled as LRP0.25 B begins at approximately (1.2, 0.56) and curves downward, ending at approximately (10.0, 0.03). A green solid line labelled as CCT0.25B begins at approximately (1.2, 0.46), curves downward, and then upward, ending at approximately (10.0, 0.4). A blue solid line labelled as NMSY begins at approximately (1.0, 0.5) and curves downward, ending at approximately (10.0, 0.34).

graph

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Figure A2.5. The probability of quasi-extinction (N < 10 adults averaged over a generation) of low-productivity stocks under an abundance-based management framework with a constant exploitation rate of 0.1 in the routine management zone that declines linearly to zero between a conservation concern threshold at 0.4·Nequilibrium and a limit reference point as indicated. The simulation incorporates realistic levels of temporally autocorrelated process error and implementation error. The example is for populations with an equilibrium abundance of 1000 adult fish and is based on the demographics of the Keogh River steelhead stock; see Johnston et al. (2000) for details. The simulations suggests that small, very unproductive stocks in variable environments with runs of good and poor survival have a high risk of extinction but that limit reference points in the range of 0.1·Nequilibrium to 0.2·Nequilibrium give results that approach that of an unexploited population. Moderately productive populations (stock productivity > 2.5 recruits per spawner) have a low extinction risk under any management framework that enforces a conservation concern threshold and a limit reference point, although at a cost in terms of access to the fishery. The simulation results allow policy comparisons but the estimated extinction risks should not be considered to be accurate.

Long Description for Figure A2.5

Figure A2.5 is titled “The probability of quasi-extinction (N < 10 adults averaged over a generation) of low-productivity stocks under an abundance-based management framework with a constant exploitation rate of 0.1 in the routine management zone that declines linearly to zero between a conservation concern threshold at 0.4·Nequilibrium and a limit reference point as indicated. The simulation incorporates realistic levels of temporally autocorrelated process error and implementation error. The example is for populations with an equilibrium abundance of 1000 adult fish and is based on the demographics of the Keogh River steelhead stock; see Johnston et al. (2000) for details. The simulations suggests that small, very unproductive stocks in variable environments with runs of good and poor survival have a high risk of extinction but that limit reference points in the range of 0.1·Nequilibrium to 0.2·Nequilibrium give results that approach that of an unexploited population. Moderately productive populations (stock productivity > 2.5 recruits per spawner) have a low extinction risk under any management framework that enforces a conservation concern threshold and a limit reference point, although at a cost in terms of access to the fishery. The simulation results allow policy comparisons but the estimated extinction risks should not be considered to be accurate.” The graph is titled “Beverton-Holt SSR.”The x-axis is titled “Stock productivity (recruits·spawner-1),” and ranges from 1 to 4. The y-axis is titled “Extinction probability” and ranges from 0.0 to 1.0. Seven different scenarios are graphed: Unfished (solid black line), no LRP (solid red line), LRP = 0.10 Nequil (blue dashed line), LRP = 0.15 Nequil (solid green line), LRP = 0.20 Nequil (purple dashed line), LRP = 0.25 Nequil (solid purple line), and LRP = CCT (red dashed line). All lines generally begin at the top left corner of the graph (between ~0.5 and 0.75 on the y-axis) and curve downward to the bottom of the graph (between ~2.4 and 3.0 on the x-axis).

graph

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APPENDIX 3. DEFINING POPULATION GROUPS

The U.S. Endangered Species Act provides for the very formally described Evolutionarily Significant Units, whereas COSEWIC, designated under SARA to assess wildlife conservation status, defines Designatable Units (DUs). Two WCT DUs were defined, coinciding with the two provincial jurisdictions in which the species occurs in Canada, namely Alberta and B.C.

Steelhead Trout (Oncorhyncus mykiss) in B.C. are managed as discrete, reproductively-isolated populations (or stocks) at the scale of third-order or larger watersheds (Johnston et al. 2002; Parkinson et al. 2005). Populations at this spatial scale appear to be sufficiently isolated, based on genetic data and related assumptions, to have independent population dynamics. Johnston et al. (2002) propose the watershed-scale level as the appropriate one to describe “stocks” or “stock aggregates” to which operational objectives for management should be applied. Furthermore, they support finer-scale management where appropriate to conserve specific ecotypes. They recognize however, that this may prove not practical because of the lack of information and resources available to manage individual stocks.

Rationale

This section describes the rationale for using genetic structure and drainages to define Population Groups:

1. Genetic structure (summarized from Costello 2008)

Molecular genetic data are widely accepted as one descriptor of within-species diversity; namely, this data provides an estimate as to what degree reproductive isolation occurs. The more isolated populations are, the greater the likelihood for locally adaptive traits to evolve independently from other populations.

Taylor et al. (2003) noted that an unusually high degree of genetic variance based on microsatellite analysis was attributed to differences among populations (32%), emphasizing the need to consider “management units” at fairly small geographic scales (compare with anadromous salmonid populations where this variation is typically < 10%). This degree of differentiation suggests significant contemporary population structure with fairly limited gene flow even at localized levels. Limited gene flow means that populations cannot rely on regular immigration for recolonization or to bolster numbers. Furthermore, many isolated populations have very little genetic variation reflecting small population sizes and no gene flow with other populations (e.g., Taylor et al. 2003). For example, B.C. populations above migratory barriers tend to have significantly fewer alleles per microsatellite locus compared to those below barriers (Taylor et al. 2003). Low variation within populations does not necessarily suggest inbreeding; however, it does emphasize the need to maintain many populations to ensure adequate conservation of genetic diversity across the species. Furthermore, these isolated populations frequently express high frequencies of alleles rare or non-existent elsewhere again emphasizing to need to maintain as many populations as possible across the landscape (Taylor et al. 2003). Overall, these results indicate that populations tend to cluster geographically and are associated with watersheds, with outliers being highly isolated headwater populations. Significant divergence among populations even where genetic exchange is possible suggests strong demographic independence and a need to manage at a local population level, despite extensive movements often observed (Taylor et al. 2003).

Three main population clusters were apparent from these genetic analyses: (1) mainstem and tributary populations in the upper Kootenay River; (2) mainstem and tributary populations in the Elk River; (3) mainstem and tributary populations from upper Fording River (above the barrier). In addition, a heterogeneous set of above barrier headwater populations from locations west of the confluence of Kootenay and Columbia rivers did not cluster with any of the other groups suggesting much greater isolation and higher potential for divergence associated with these isolated habitats. However, significant variation among populations lacking any obvious barriers suggests significant isolation even among adjacent populations (Taylor et al. 2003).

2. Major drainages

Hierarchical structure as reflected by drainage organization is considered an appropriate way to classify freshwater systems according to key spatial and temporal processes (see Ciruna et al. 2007 and references therein). B.C. has adopted such a freshwater classification framework to describe systems at three spatial scales; Freshwater Ecoregions (of which there are 5), Ecological Drainage Units (EDUs, of which there are 36) and finally at the most detailed level River and Lake Ecosystem Types. We roughly followed the second tier of this classification framework to identify major drainages within the native range for WCT. These EDUs are intended to capture both historic (i.e., zoogeography) and contemporary (i.e., physiographic and hydrologic) processes influencing species distribution (Ciruna et al. 2007). The original EDUs include Upper Columbia, Columbia-Arrow Lakes, Upper Kootenay, Lower Kootenay, Kettle, Flathead and Thompson; all of which reflect different zoogeographic, physiographic and hydrologic traits (Ciruna et al. 2007). Parkinson et al. (2005) also considered major drainages in considering hierarchical organization of diversity for steelhead, rationalizing that populations evolving in a similar geographic regions likely share adaptive traits.

Six major drainage basins fall within WCT native range in B.C. including the Upper Kootenay (above the original location of Kootenai Falls below Kookanusa Reservoir), Elk (including tributaries above Elko Dam), West Kootenay (Kootenay Lake and downstream), Columbia (including Arrow Lakes, Pend d’Oreille), Kettle and South Thompson.

Population Groups

In combining the identified six watershed units and three genetic groupings, seven Population Groups were defined (Table A3.1). Given that Upper Fording genetic group occurred above a natural barrier, it will be treated as other “headwater” isolated populations but it is included in the Elk Population Group. Headwater populations will be treated as “special cases” within their Population Group, given their highly isolated, vulnerable nature.

Long Description for Table A3.1

Table A3.1 is titled “Defined Population Groups based on genetic data and delineated major drainages within native WCT range.” The table is read horizontally from left to right, and consists of four columns and nine rows. The top row contains the column headings: Drainages, Additional genetic groups within drainages, Population Group, and Range status.

Table A3.1. Defined Population Groups based on genetic data and delineated major drainages within native WCT range
DrainagesAdditional genetic groups within drainagesPopulation GroupRange status
ElkElk River and tributariesElkCore
ElkUpper Fording River and associated tributaries (above barrier)ElkCore
FlatheadN/A (not well represented)FlatheadCore
Upper KootenayMainstem Upper Kootenay and tributariesUpper KootenayCore
West KootenayN/A (not well represented)West KootenayCore/Peripheral
ColumbiaN/A (not well represented)ColumbiaPeripheral
KettleAbove barrier setKettlePeripheral
South ThompsonAbove barrier setSouth ThompsonPeripheral

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APPENDIX 4. INTROGRESSION

Hybridization with non-native trout species leading to introgression and hybrid swarms is persistently identified as one of the greatest threats to WCT throughout its North American range. In fact, it is estimated that non-hybridized populations of WCT now persist in less than 10% of their historic range, and those are frequently restricted to isolated headwater systems highly vulnerable to extinction associated with stochastic events (Trotter 2008).

A total of 114 sites (some including lower, upper, and in some cases middle sections of the same river) representing 88 waterbodies (both streams and lakes) were assessed for hybrid presence (see Table A4.2). As it is very difficult to differentiate between very low levels of hybridization and polymorphisms within the species (i.e., < 1% admixture) (Allendorf et al. 2001), any populations with WCT genotypes representing 99% or more of the population are considered pure WCT.

Several studies considered patterns of hybridization spread and potential mechanisms that facilitate or limit spread in B.C. WCT populations (Hitt et al. 2003; Rubidge and Taylor 2005; Boyer et al. 2008; Bennett and Kershner 2009). Key conclusions from these studies include:

  1. Backcrosses (i.e., beyond F1 hybrids) are the most common form of hybrid in the B.C. populations studied, indicating an ongoing ability to interbreed among the various hybrid and pure forms.
  2. Some populations are approaching hybrid swarm status where no pure WCT genotypes remain.
  3. Admixture with Rainbow Trout decreases with upstream distance from Rainbow Trout source or hybrid swarm.
  4. Populations above migration barriers contain fewer hybrids than below barriers.
  5. The role of environmental factors in limiting the spread of hybridization may not be as important as demographic factors.
  6. Hybrids appear to facilitate further spread of Rainbow Trout genes to neighbouring populations via increased straying rates compared to pure WCT.
  7. Much of the core B.C. range is not the stronghold for remaining pure WCT populations we had thought it to be.
  8. Although all B.C. stocking of Rainbow Trout into native WCT range is now conducted using sterile fish which will prevent further hybridization at new locations, introgressed populations can persist indefinitely (although can be diluted through time), making the protection of non-introgressed populations the highest priority.

In summary, these studies indicate that two main Population Groups are seriously compromised by non-native Rainbow Trout introgression. Some pure WCT populations still exist in these groups but these populations tend to be located in upstream portions of tributaries. The Flathead River appears to be the only group with no hybridization present, at least in the Canadian portion of the river. Survey work has been too limited to draw conclusions about the status of peripheral Population Groups. WCT appear to be naturally limited to tributaries while native Rainbow Trout tend to dominate downstream mainstems in these areas suggesting natural reproductive isolation has prevented extensive introgression here.

Long Description for Table A4.2

Table A4.2 is titled “Percent of populations considered to be pure WCT based on genotypic data by Population Group. Note that in some cases, the approximate location within the stream was reported by researchers (L = lower, M = Mid, U = upper), otherwise location was reported as “unknown.” (WCT = Westslope Cutthrout Trout, RBT=Rainbow Trout).” The table is read horizontally from left to right, and consists of seven columns and 24 rows. The top row contains the column headings: Population Group, Location in stream, >98% WCT, 95-98% WCT, <95% WCT, Pure RBT, and % Pure WCT populations. A grey sub-total row is located beneath each population group, and a grand total row is found at the very bottom.

Table A4.2. Percent of populations considered to be pure WCT based on genotypic data by Population Group. Note that in some cases, the approximate location within the stream was reported by researchers (L = lower, M = Mid, U = upper), otherwise location was reported as “unknown.” (WCT = Westslope Cutthrout Trout, RBT=Rainbow Trout)
Population GroupLocation in stream>98% WCT95 –98% WCT<95% WCTPure RBT% Pure WCT populations
ElkL125012.5
 M101050.0
 U302060.0
 unknown2000100.0
Elk Total (11 waterbodies) 728041.2
FlatheadL1000100.0
 U2000100.0
 unknown11000100.0
Flathead Total (8 waterbodies) 14000100.0
Upper KootenayL3113017.7
 M304042.9
 U512062.5
 unknown1242066.7
Upper Kootenay Total
(45 waterbodies)
 23621048.0
West Kootenay Total
(3 waterbodies)
 3000100.0
ColumbiaL2000100.0
 M1000100.0
 U2000100.0
 unknown1612372.7
Columbia Total (18 waterbodies) 2112377.8
Kettle Total (2 waterbodies) 101050.0
South Thompson Total
(1 waterbody)
 1000100.0
Grand total (88 waterbodies) 70932261.4

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APPENDIX 5. ABUNDANCE

Information on population abundance is extremely limited for WCT in B.C. Some short-term monitoring has been undertaken in the East Kootenays to estimate abundance in some high priority streams.

Snorkel surveys have been conducted at a number of index sites for several popular WCT streams to estimate abundance and densities. Snorkel surveys appear to be fairly efficient (i.e., snorkelers are able to observe most fish) for adult and sub adult WCT (reviewed in Hagen and Baxter 2009). Table A5.1 summarizes abundance estimates and trends for WCT rivers for which surveys have been conducted.

Long Description for Table A5.1

Table A5.1 is titled “Summary of abundance and density estimates for WCT in a small set of streams from the Elk and Upper Kootenay Population Groups.” The table is read horizontally from left to right, and consists of three columns and 12 rows. The top row contains the column headings: System, Abundance (sub-divided into: Year, Estimate, and Fish/km), and Conclusion. Footnotes found throughout the table further explanation with respect to references cited.

Table A5.1. Summary of abundance and density estimates for WCT in a small set of streams from the Elk and Upper Kootenay Population Groups.
SystemAbundanceConclusion
YearEstimateFish/km
Wigwam Rivera, b - between Desolation and Lodgepole creeks - 42.1 km length2008> 300 mm = 701
> 400 mm = 189
12–24
4–6
Shift in densities upstream over time, but overall abundance appears to be fairly stable, 2008 estimate for large fish was higher than for 2001 or 2002 upstream of Bighorn Creek; 2008 estimate for large fish was lower than for 2001 or 2002 downstream of Bighorn Creek
2002> 300 mm = 341
> 400 mm = 95
5–32
2–9
2001> 300 mm = 295
> 400 mm = 64
10–33
2–7
Michel Creeka - three sections surveyed (upper, middle, and lower) - total length is 36.7 km2008> 300 mm = 1704
> 400 mm = 611
46
17
A highly productive population with a large proportion of very large fish
Lower St. Mary Rivera - 54.1 km2008> 300 mm = 236044Recovery from low abundance in late 1980s/early 1990s evident but highest density was in 1982 suggesting carrying capacity is greater than what is currently observed. Note also a clear reduction in fork length from a mean of 342 mm in 1981 to 271 mm in 1989 was observedc
1994> 300 mm = 173132
1990> 300 mm = 92017
1989> 300 mm = 108220
1984> 300 mm = 243545
1982> 300 mm = 416677
Upper St. Mary Rivere
3.9 km (Mud Hole Rd. to Meachen Bridge)
2010> 300 mm = 49317 
Upper St. Mary Rivera, e - 2.8 (km 43.5 to Pyramid Cr.)2010
2008
> 300 mm = 493
> 300 mm = 49
> 400 mm = 10
21
14
3
Fairly limited in extent of coverage
Elk Rivera - 4.9 km2008> 300 mm = 192*
> 400 mm = 108*
39*
22*
Feasibility study only but observed 192 trout > 300 mm, over half of which were > 40 mm; *note that these are unadjusted counts
Upper Bull River - between Van Creek and Aberfeldie headpondc – 11 km2006> 300 mm = 538
> 400 mm = ?
33
4
WCT are widely distributed except for first km up stream/s of headpond, with densities similar to those viewed elsewhere in river
Upper Bull Riverd - between Sulphur Creek and Van Creek - 17.5 kmYear?> 300 mm = 860
> 400 mm = ?
39
3
Included both a catch and release section and an adjacent harvest section;
White River (N. Fork)e
Goat Camp to Colin Cr. - 2.7 km
2010> 300 mm = 26010.2 
White River (N. Fork)e - Nilksuka upstream - 2.3 km2010See above6.5 

From aHagen and Baxter 2009, bBaxter and Hagen 2003, cBaxter 2006, dBaxter 2004, eK. Heidt, pers. comm., 2011.

Densities vary with stream with the upper St. Mary and Wigwam rivers clearly less productive than Michel Creek and lower St. Mary River. Wigwam’s unexpanded estimate suggests densities that are even higher than the other streams surveyed (Hagen and Baxter 2009).

Catch per unit effort data (CPUE) can also provide an index of fish abundance. A recent radio-tagging study in the lower Elk River indicated that CPUE values for fish 350 mm long or greater were considerably larger in the lower Elk River (Elko Dam to Sparwood, catch and release and harvest sections combined = 2.36 fish per hour) compared to the upper Elk River (Sparwood to lower Elk Lake, catch and release and harvest sections combined = 0.97 fish per hour) (Westslope Fisheries Ltd. 2003).

With respect to headwater fluvial populations, a modeling exercise considered population responses to carrying capacity of habitat in terms of likelihood of extinction (Hilderbrand 2003). Results indicated that likelihood of extinction declined significantly as carrying capacity increased, even if these increases were very modest. This reflects a general negative relationship between extinction rate and population size. The conclusion was that we should maintain as large a population size as possible for small isolated populations and maintain supporting habitat. Big gains can be made through habitat length increase (and removing non-native species) and habitat quality. Furthermore, this study noted that immigration to small isolated systems can reduce extinction risk without risk to source population. Thus we should maintain natural connectivity between core populations as peripheral populations. However, this benefit decreases as population dynamics between large migratory and small isolated populations become increasingly synchronized.

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APPENDIX 6. ANGLING MORTALITY

During snorkel survey studies in 2008 (Hagen and Baxter 2009) hooking injury was documented. Only Wigwam and Michel systems could be adequately assessed due to visibility limitations in other systems. In both systems, the proportion of fish with injuries increased significantly with size as follows: 0–54% for fish < 200 mm long, 5–76% for fish 200–300 mm long, 15–92% for fish 300–400 mm long to 26–94% for fish > 400 mm long. Michel Creek in general had higher frequencies of injuries for all size groups, likely owing to its small stream size and vulnerability of fish.

Given that hooking mortality is typically 3–5%, cumulative hooking mortality over an entire season may be significantly more. This is a particular concern for a species like WCT, which may be caught multiple times in one season.

A radio-tagging study that tracked adults for 2 years in the Elk River estimated rates of mortality associated with various sources as follows: 12.5% (spawning), 5% (avian), and (17.5%) angler harvest (Westslope Fisheries Ltd. 2003).

APPENDIX 7. RIPARIAN HABITAT BUFFERS

Forestry-related Issues

Oliver (2009) considered the impact of forestry-related activities to WCT habitat and found that in an evaluation of 50 watersheds within the Upper Kootenay and Columbia Population Groups, only 5 exceeded sensitivity guidelines and greatest sensitivities were in smaller basins. Higher hazard ratings for surface erosion and mass wasting were consistent for basins with equivalent clearcut area greater than 10%. It is uncertain how representative this small portion of streams is for WCT in B.C. Forestry practices have generally improved dramatically over the past 30 years, and current practices under the B.C. Forest and Range Practices Act (FRPA, implemented in 2004) are intended to provide adequate riparian habitat buffer zones for fish-containing streams. Palliser Creek is currently the only stream within the range of WCT identified as a Fisheries-Sensitive Stream under FRPA to which more stringent management guidelines are applied to protect fisheries values. Section 7.3.4, Habitat Access (also see Appendix 10) discusses road crossings more specifically.

Agriculture-related Issues

Of the 52 Crown range units identified in the Southern Rocky Mountain Trench and Elk Valley, 22 are considered active and 8 may be of particular concern to WCT due to cattle access to streams (Oliver 2009). Sensitivity is greatest where streams are small.

Mining-related Issues

There are a few examples within the range of WCT of where rock drains have permanently eliminated fish habitat and passage (e.g., Line and Kilmarnock creeks), and temporary diversions may also affect fish passage (Oliver 2009). Numerous off-channel areas and wetlands have been compromised or eliminated in the Elk Valley by tailings and settling ponds (Oliver 2009). The extent to which this has compromised riparian habitat within WCT range has not been calculated; impacts are likely only significant for a limited number of streams.

Urban Development Issues

Impacts to riparian habitats have probably best been described for Cranbrook where the WCT stream, Joseph Creek, flows through the city. Altered surface run-off patterns associated with paved surfaces and storm sewer inputs have resulted in elevated sediment loads entering the stream at certain high water times (Oliver 2009). This issue is undoubtedly repeated in all communities within the WCT range (i.e., Kimberley, Fairmont, Golden, Revelstoke, Castelgar, Invermere, and Trail) but is probably greatest where receiving waters involve relatively small streams rather than large mainstems (like the Columbia and Elk rivers) were impacts are diluted (Oliver 2009).

Roads and Transportation Line Issues

Probably the greatest concern is related to the number of highway and railway crossings on smaller WCT streams, affecting passage to other habitats (Oliver 2009). The actual impact associated with riparian habitat is probably very localized and associated more with construction.

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APPENDIX 8. NATURAL FLOW CONDITIONS

Almost all of the native WCT range in B.C. falls within the Southern Interior Mountains Ecoprovince, a region characterized by two distinct climate regimes: one occurs in the mountainous areas and the other in the Southern Rocky Mountain Trench. The Trench is naturally flow-sensitive, and a recent analysis indicated that unit run-off was generally low in all ecosections within the ecoprovince but very low (i.e., dry) within the East Kootenay Trench, as well as the McGillivary Range (Ptolemy 2010). These two ecosections contain two tributaries with known fish-flow conflicts, Wolfe and Joseph creeks. In particular, it is estimated that adult trout upstream passage and spawning flows of near 124% mad (mean annual discharge) are required for days to weeks during May-June on small streams such as Joseph Creek (Ptolemy 2010). Spring flows in 1977 averaged 136 L•s-1 or 8.5% mad with resultant spawning failures. Failures also likely occurred in 1992 and 2001 (Oliver 2003).

APPENDIX 9. SITE FIDELITY

WCT in the Elk River demonstrate site fidelity to both summer feeding areas and spawning locations, not only at the population level (i.e., using genetic data) but also at the individual fish level as demonstrated by a 2-year radio-tagging study (Westslope Fisheries Ltd. 2003). In fact, 25% of the tagged adults migrated to the same site in 2 consecutive years. The average length of stream used by WCT in this study to winter and spawn was 11.2 km, and ranged from 1.8 to 35.9 km. Furthermore, fish in the upper portion of the Elk River used twice as much river habitat over the course of a year than those in the lower river, undoubtedly reflecting availability of suitable habitat particularly ice-free habitats for overwintering (Westslope Fisheries Ltd. 2003).

This fidelity is clearly expressed in the significant genetic population structure evident among B.C. populations where a considerable amount of genetic variation is attributed to differences among populations (i.e., 32% of total variation; Taylor et al. 2003). Although WCT may range considerably throughout a year using various habitats to feed, rear, spawn, and overwinter; local population structure indicates that homing in this species is very strong. From a conservation perspective, these results indicate that a breadth of habitats and migratory corridors must be maintained for this species.

APPENDIX 10. STREAM CROSSINGS

Table A10.1. The estimated number of crossings associated with forestry roads in seven WCT Management Group areas that have been assessed as being a problem for fish passage.

A total of 69,131 crossings associated with forestry roads in seven WCT Management Group areas were estimated based on a modeling exercise, of which about two-thirds (42,483) of these are modelled to be on fish habitat (C. Mount, pers. comm., 2011). A total of 2017 (< 5%) of these crossings have been assessed for fish passage problems. Of that subset, roughly half are Closed Bottom Structures (CBS). Data provided by C. Mount. Assessed systems are all assumed to be fish habitat.

Long Description for Table A10.1

Table A10.1 is titled “The estimated number of crossings associated with forestry roads in seven WCT Management Group areas that have been assessed as being a problem for fish passage.” The table is read horizontally from left to right, and consists of three columns and 46 rows. The top row contains the column headings: WCT Population Group, Crossing Type, Crossing Subtype, Assessed (sub-divided into: n Total, n Barrier, n Potential Barrier, Pct Barrier, Pct Barrier or Potential Barrier), and Modelled (sub-divided into: n Crossings (Fish Habitat), and n Crossings (non Fish Habitat). A grey sub-total row is located beneath each population group, and two yellow grand total rows are found at the very bottom. A footnote at the bottom of the table offers further explanation with respect to acronyms used.

 

Table A10.1. The estimated number of crossings associated with forestry roads in seven WCT Management Group areas that have been assessed as being a problem for fish passage.
   AssessedModelled
WCT Management GroupCrossing TypeCrossing Subtypen Totaln Barriern Potential BarrierPct BarrierPct Barrier or Potential Barriern Crossings (Fish Habitat)n Crossings (non Fish Habitat)
ColumbiaCBSOVAL CULVERT22-100%100%--
ColumbiaCBSROUND CULVERT2331081146%51%--
ColumbiaNCS-57--0%0%--
ColumbiaNCSFORD7--0%0%--
ColumbiaOBS-8--0%0%--
ColumbiaOBSBRIDGE82--0%0%--
ColumbiaOBSPIPE ARCH31-33%33%--
ColumbiaOBSWOOD BOX CULVERT24--0%0%--
ColumbiaOTHER-6--0%0%--
Columbia Sub Total (all)allall4221111126%29%12,41610,243
Columbia Sub Total (CBS only)CBSall CBS2351101147%51%--
KettleCBSOTHER21-50%50%--
KettleCBSROUND CULVERT174623236%54%--
KettleNCS-34--0%0%--
KettleNCSFORD11--0%0%--
KettleOBSBRIDGE4--0%0%--
KettleOBSPIPE ARCH73-43%43%--
KettleOBSWOOD BOX CULVERT5--0%0%--
Kettle Sub Total (all)allall237663228%41%9,0182,126
Kettle Sub Total (CBS only)CBSall CBS176633236%54%--
South ThompsonCBSROUND CULVERT3441472343%49%--
South ThompsonNCS-105--0%0%--
South ThompsonNCSFORD2--0%0%--
South ThompsonOBSBRIDGE105--0%0%--
South ThompsonOBSPIPE ARCH4--0%0%--
South ThompsonOBSWOOD BOX CULVERT1--0%0%--
South ThompsonOTHER-115--0%0%--
South Thompson Sub Total (all)allall6761472322%25%4,4472,636
South Thompson (CBS only)CBSall CBS3441472343%49%--
Upper KootenayCBSROUND CULVERT101711170%81%--
Upper KootenayNCS-85--0%0%--
Upper KootenayNCSFORD62--0%0%--
Upper KootenayOBSBRIDGE7--0%0%--
Upper KootenayOBSWOOD BOX CULVERT82225%50%--
Upper KootenayOTHER-71114%29%--
Upper Kootenay Sub Total (all)allall270741427%33%9,3504,295
Upper Kootenay Sub Total (CBS only)CBSall CBS101741173%84%--
West KootenayCBSROUND CULVERT15196664%68%--
West KootenayNCS-124--0%0%--
West KootenayNCSFORD9--0%0%--
West KootenayOBSBRIDGE97--0%0%--
West KootenayOBSPIPE ARCH1--0%0%--
West KootenayOBSWOOD BOX CULVERT22--0%0%--
West KootenayOTHER-81-13%13%--
West Kootenay Sub Total (all)allall41297624%25%4,0835,499
West Kootenay Sub Total (CBS only)CBSall CBS15196664%68%--
----------
Elk Sub Total (all)allall0----22511536
Elk Sub Total (CBS only)CBSall CBS0------
----------
Flathead Sub Total (all)allall0----918313
Flathead Sub Total (CBS only)CBSall CBS0------
----------
TOTAL (all assesments)allall20174958625%29%42,48326,648
TOTAL (CBS only)CBSall CBS10074908349%57%--

Crossing Type: CBS = closed bottom structure; NCS = no crossing structure (a ford crossing); OBS = open bottom structure

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APPENDIX 11. FISHING QUALITY

Table A11.1 summarizes the status of angler use on the seven Classified Waters and comes directly from Tepper (2008a). It summarizes data collected from River Guardians Program from Elk in 2002, St. Mary in 2003, and all seven rivers in 2004–2008.

Long Description for Table A11.1

Table 11.1 is titled “Catch per unit effort (CPUE) and fishing quality comments for several Quality Waters systems.” The table is read horizontally from left to right, and consists of three columns and nine rows. The top row contains the column headings: River, CPUE, and Comment on quality.

Table A11.1. Catch per unit effort (CPUE) and fishing quality comments for several Quality Waters systems
RiverCPUEComment on quality
Upper KootenayN/AHigh – based on limited information
White1.0 (2007)
0.8 (2008)
Good to excellent but based on low interview numbers, light angler use but may be increasing
Skookumchuck0.9–1.9 (2004–2008), no trendQuality improving, slightly crowded, assuming guides reporting properly, non-guided non-resident anglers over target allocation of 180 angler days by 27%
St. Mary0.8–1.8 (2003–2007), lower recentlyQuality improved to 2006, dropped slightly in 2007 and 2008, but still considered high to excellent; CPUE lower in 2007 and 2008 compared to previous years; non-resident (guided and non-guided) considered well below target allocation of 2750 angler days, considered not crowded
Bull0.9–1.5 (2004–2008), no trendQuality improving and considered high, crowding may be increasing, non-resident (guided and non-guided) considered well below target allocation of 1100 angler days
Elk0.9–1.5 (2002–2008), no trendQuality improved until 2007 and 2008 when a slight drop was noted, possibly due to more crowding but still considered high to excellent, non-resident and non-resident, non-guided anglers over target allocation of 3540 angler days by 57%
Michel (tributary of Elk not separately classified)1.2–2.0 (2004–2008), no trendQuality improved and considered high to excellent, crowding may be increasing (particularly as perceived by local resident anglers)
Wigwam0.8–1.4 (2004–2008), trending downwardQuality was improving until 2007 and 2008 but still considered high to excellent; CPUE lower in 2007 and 2008 compared to previous years, non-resident non-guided angler days exceeded target allocation of 180 angler days by 444% in 2006, crowding may be increasing with “very crowded” considered by local residents, guides, and non-residents

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APPENDIX 12. FISH STOCKING

Threat Associated with Fish Stocking

Several observed or potential impacts to WCT are associated with the long history of fish stocking in B.C. The three greatest impacts are:

  1. Hybridization leading to introgression - WCT interbreed with non-native closely related trout species like Rainbow Trout, resulting in fertile hybrids that continue to back cross with WCT, Rainbow Trout, or other hybrids. WCT are particularly susceptible to this where they have evolved in isolation of other closely related species and have not therefore evolved reproductive isolation mechanisms (i.e., upstream of Kootenai Falls). The result if allowed to continue is a hybrid swarm where neither parental genotype remains within the population. Hybrids and backcrossed individuals may be intermediate in phenotype and adaptive abilities. They have also been shown to stray more. The result from an ecological perspective is a loss of local population structure and local adaptive traits. These traits may be precisely why WCT have continued to persist for thousands of years in conditions considered too harsh for many other freshwater fish species. Clearly this is a major threat to populations in the core native range in B.C., and has also been identified as one of the leading causes for the precipitous declines in pure WCT populations in Montana and Alberta.
  2. Competition and displacement - Species like Rainbow Trout and Eastern Brook Trout are more productive (i.e., reproduce at an earlier age, produce more offspring) than native WCT, and tend to be more resilient to fishing pressure. Furthermore, these salmonids may fare better in degraded conditions (increased water temperatures, increased siltation) to which WCT are more sensitive, and may have a competitive advantage as they emerge earlier as fry (summarized in Costello 2008). This combination of factors may explain the predominance of Eastern Brook Trout in Joseph Creek (Oliver 2009).
  3. Outbreeding depression - Although this threat has not been evaluated for WCT in B.C. or elsewhere, it is worth considering. Hatchery-origin WCT have been released in watersheds of southeastern B.C. for decades. Since the early 1970s, all fish have originated from a single-source population in Connor Lakes. This source has been genetically confirmed to be pure WCT but all releases continue to be diploid. Given the significant localized substructuring apparent in wild populations, there is some risk associated with releasing a non-local (i.e., not same watershed) fish capable of reproducing.

Stocking History in B.C.

The stocking of non-native trout species into waters containing native WCT has been one of the greatest threats to the persistence of the species throughout much of its original range.

To attempt a more focused consideration of WCT waterbodies, Table A12.1 considers only stocked waterbodies in which WCT have also been observed based on the provincial FISS database records. Predictive modelling to identify those waterbodies likely to support WCT will enable a more thorough analysis of hatchery practices throughout the native WCT range in B.C.

In the central groups, over 50% of the lakes in which WCT have been observed are also stocked with WCT. Most of the recent stocking initiatives are limited to lake stocking within these areas but some WCT stocking appears to be continuing in riverine situations. While this may not affect genetic integrity at the species level, it may act to genetically homogenize populations where the non-local hatchery stock interbreeds with local wild populations, particularly given the unclear origins of the Connor Lakes hatchery fish.

With respect to Rainbow Trout stocking within the core range of WCT outside of native Rainbow Trout range, the Upper Kootenay Population Group has seen most introductions. Only one lake and one stream received Rainbow Trout in the Flathead. Only 8 waterbodies in the Elk River reported to contain WCT received Rainbow Trout. Note that Summit Lake (in Elk group), Joseph Creek, and Bull River (both in Upper Kootenay group), which all contain native WCT populations, also directly received hatchery Rainbow Trout 10 or more times.

Long Description for Table A12.1

Table A12.1 is titled “Number of streams and lakes (as defined by unique “blueline number” up until 2008; B. Woods, pers. comm. Ongoing) where WCT has been observed at least once for which at least one stocking event has also occurred for CS (Cutthroat x Rainbow Trout cross), CT (Cutthroat Trout, probably coastal), EBT (Eastern Brook Trout), RBT (Rainbow Trout), and WCT. Total WCT = the total number of streams and lakes were WCT have been observed.” The table is read horizontally from left to right, and consists of nine columns and ten rows. The top row contains the column headings: Population Group, Waterbody type, Total WCT, CS, CT, EBT, RBT, WCT, and Total Stocked. The rows all the column headings to the right of Population group are further sub-divided into Stream and Lake. A total row is found at the very bottom of the table.

Table A12.1. Number of streams and lakes (as defined by unique “blueline number” up until 2008; B. Woods, pers. comm. Ongoing) where WCT has been observed at least once for which at least one stocking event has also occurred for CS (Cutthroat x Rainbow Trout cross), CT (Cutthroat Trout, probably coastal), EBT (Eastern Brook Trout), RBT (Rainbow Trout), and WCT. Total WCT = the total number of streams and lakes were WCT have been observed.
Population GroupWaterbody typeTotal WCTCSCTEBTRBTWCTTotal stocked
ElkStream13400432229
Lake3600052025
FlatheadStream85000167
Lake1700011213
Upper KootenayStream406035154366
Lake114017215382
West KootenayStream246124213058
lake81002164765
ColumbiaStream11700291930
Lake54010112941
KettleStream12000033
Lake7000077
South ThompsonStream6000156
Lake4000314
TotalStream1006151540128189
 Lake31302954169234

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APPENDIX 13. THREATS ASSESSMENT

While the moderate to high rated threats identified for each Population Group are discussed in detail in the main body of the document, lower ranking threats, which may include wide-ranging threats and threats with significant data gaps, may play an important role in exacerbating other factors already threatening WCT. For example, it is suspected that invasive species (COSEWIC 2007) such as spiny-rayed fishes, and zebra and quagga mussels, may play a role in competition for shared resources. However, due to knowledge gaps, we cannot be certain how strong of a role they play. Although fishing pressure was not listed as a high ranking threat for at-risk populations, it is widespread across WCT’s entire range, and population reductions have the potential to enhance vulnerability to stochastic events (e.g., epizootics; COSEWIC 2007). Mayhood (2009) highlights that WCT are most vulnerable to overharvest in small-stream populations in part due to their vulnerability to increased road access to these areas. Finally, although not identified as a single threat, habitat degradation is a recurring theme across most threats to WCT. For example, forest harvest, mining, linear projects, agriculture, development, and water use all potentially affect WCT habitat quality and quantity. In particular, carrying capacity is diminished significantly by habitat degradation via fine sedimentation, barrier creation, and climate warming in Albertan populations of WCT (Mayhood 2009); details on equivalent effects in B.C. are lacking. Trends suggest significant amounts of habitat degradation over the last 100 years, in part due to recent increases in access to waterbodies, and with formal protection measures only recently coming into force (COSEWIC 2006). Consideration of the influence of invasive species, fishing pressure, and habitat degradation is thus important when interpreting results of the threat assessment tool.

The following table contains the entire ranked list of threat mechanisms and associated sources.23 Refer to Hatfield and Long (2010) for more information on the threat assessment process used.

Long Description for Table A13.1

Table A13.1 is titled “Output from threats assessment tool with all threats considered. Threats sorted by Population Group, then by threat mechanisms.” The table is read horizontally from left to right, and consists of eight columns and 438 rows. The top row contains the column headings: Population Group, Threat meachanism 1st Level, Threat mechanism 2nd Level, Threat Source, Scope, Severity, and Timing. Footnotes on the column headers Population Group, Scope, Severity, Timing and Threat Impact offer further explanation.

Table A13.1. Output from threats assessment tool with all threats considered. Threats sorted by Population Group, then by threat mechanisms.
Population Group uThreat mechanism
1st Level
Threat mechanism
2nd Level
Threat sourceScope vSeverity wTiming xThreat Impact y
ColumbiaHabitatAltered community dynamicsInvasive SpeciesUnknownUnknownunknownUnknown
ColumbiaHabitatAltered community dynamicsClimate Change & Severe WeatherUnknownUnknownFuture onlyUnknown
ColumbiaHabitatAltered community dynamicsWater Use – permanent withdrawal – consumptiveRestrictedModerateOngoing, stableLow
ColumbiaHabitatAltered community dynamicsWater Use - temporary diversions/dams, non-consumptiveSmallSlightOngoing, stableLow
ColumbiaHabitatAltered community dynamicsIndustrial and Municipal DischargesSmallSlightOngoing, stableLow
ColumbiaHabitatAltered community dynamicsResidential, Recreational and Commercial DevelopmentSmallSlightOngoing, stableLow
ColumbiaHabitatAltered flow regimeClimate Change & Severe WeatherLargeUnknownOngoing, increasingUnknown
ColumbiaHabitatAltered flow regimeWater Use – permanent withdrawal – consumptiveRestrictedSeriousOngoing, increasingMedium
ColumbiaHabitatAltered flow regimeWater Use - temporary diversions/dams, non-consumptiveLargeModerateOngoing, increasingMedium
ColumbiaHabitatAltered flow regimeAgricultureRestrictedSlightOngoing, stableLow
ColumbiaHabitatAltered flow regimeForest HarvestRestrictedModerateOngoing, stableLow
ColumbiaHabitatAltered flow regimeIndustrial and Municipal DischargesSmallSlightOngoing, stableLow
ColumbiaHabitatAltered flow regimeMiningSmallSlightOngoing, stableLow
ColumbiaHabitatAltered flow regimeResidential, Recreational and Commercial DevelopmentSmallSlightOngoing, stableLow
ColumbiaHabitatAltered flow regimeOil and GasNegligibleNegligible0Negligible
ColumbiaHabitatAltered flow regimeLinear ProjectsNegligibleNegligible0Negligible
ColumbiaHabitatFish passageForest HarvestLargeUnknownOngoing, diminishingUnknown
ColumbiaHabitatFish passageClimate Change & Severe WeatherUnknownUnknownOngoing, stableUnknown
ColumbiaHabitatFish passageWater Use – permanent withdrawal – consumptiveRestrictedSeriousOngoing, stableMedium
ColumbiaHabitatFish passageLinear ProjectsLargeModerateOngoing, stableMedium
ColumbiaHabitatFish passageWater Use - temporary diversions/dams, non-consumptiveLargeSlightOngoing, stableLow
ColumbiaHabitatFish passageMiningSmallSlightOngoing, stableLow
ColumbiaHabitatFish passageResidential, Recreational and Commercial DevelopmentSmallSlight0Low
ColumbiaHabitatFish passageOil and GasNegligibleNegligible0Negligible
ColumbiaHabitatInstream mechanical disturbanceAgricultureSmallSlightOngoing, stableLow
ColumbiaHabitatInstream mechanical disturbanceWater Use - temporary diversions/dams, non-consumptiveSmallSlightOngoing, stableLow
ColumbiaHabitatInstream mechanical disturbanceWater Use – permanent withdrawal – consumptiveRestrictedSlightOngoing, increasingLow
ColumbiaHabitatInstream mechanical disturbanceResidential, Recreational and Commercial DevelopmentSmallSlight0Low
ColumbiaHabitatInstream mechanical disturbanceLinear ProjectsLargeModerateOngoing, stableMedium
ColumbiaHabitatInstream mechanical disturbanceForest HarvestNegligibleNegligibleOngoing, diminishingNegligible
ColumbiaHabitatInstream mechanical disturbanceMiningNegligibleNegligible0Negligible
ColumbiaHabitatLarge scale habitat modificationsWater Use - temporary diversions/dams, non-consumptiveLargeUnknownOngoing, stableUnknown
ColumbiaHabitatLarge scale habitat modificationsAgricultureSmallSlightResidual onlyLow
ColumbiaHabitatLarge scale habitat modificationsMiningSmallSlightOngoing, stableLow
ColumbiaHabitatLarge scale habitat modificationsResidential, Recreational and Commercial DevelopmentSmallSlightOngoing, increasingLow
ColumbiaHabitatLarge scale habitat modificationsWater Use – permanent withdrawal – consumptiveRestrictedNegligibleOngoing, stableNegligible
ColumbiaHabitatLarge scale habitat modificationsInvasive SpeciesNegligibleNegligible0Negligible
ColumbiaHabitatLarge scale habitat modificationsOil and GasNegligibleNegligible0Negligible
ColumbiaHabitatRiparian clearing and alterationForest HarvestLargeModerateOngoing, stableMedium
ColumbiaHabitatRiparian clearing and alterationMiningSmallSlightOngoing, stableLow
ColumbiaHabitatRiparian clearing and alterationAgricultureRestrictedSlightOngoing, stableLow
ColumbiaHabitatRiparian clearing and alterationWater Use – permanent withdrawal – consumptiveSmallSlightOngoing, stableLow
ColumbiaHabitatRiparian clearing and alterationResidential, Recreational and Commercial DevelopmentSmallSlightOngoing, increasingLow
ColumbiaHabitatRiparian clearing and alterationLinear ProjectsSmallSlightOngoing, stableLow
ColumbiaHabitatRiparian clearing and alterationWater Use - temporary diversions/dams, non-consumptiveSmallNegligibleOngoing, stableNegligible
ColumbiaHabitatRiparian clearing and alterationOil and GasNegligibleNegligible0Negligible
ColumbiaHabitatSmall scale habitat modificationsInvasive SpeciesUnknownUnknownFuture onlyUnknown
ColumbiaHabitatSmall scale habitat modificationsAgricultureSmallSlightOngoing, stableLow
ColumbiaHabitatSmall scale habitat modificationsWater Use – permanent withdrawal – consumptiveRestrictedSlightOngoing, stableLow
ColumbiaHabitatSmall scale habitat modificationsMiningSmallSlightOngoing, stableLow
ColumbiaHabitatSmall scale habitat modificationsResidential, Recreational and Commercial DevelopmentSmallSlight0Low
ColumbiaHabitatSmall scale habitat modificationsLinear ProjectsSmallSlightResidual onlyLow
ColumbiaHabitatSmall scale habitat modificationsWater Use - temporary diversions/dams, non-consumptiveSmallNegligibleOngoing, stableNegligible
ColumbiaHabitatSmall scale habitat modificationsOil and GasNegligibleNegligible0Negligible
ColumbiaHabitatWater qualityInvasive SpeciesUnknownUnknownFuture onlyUnknown
ColumbiaHabitatWater qualityForest HarvestLargeModerateOngoing, increasingMedium
ColumbiaHabitatWater qualityMiningSmallSlightResidual onlyLow
ColumbiaHabitatWater qualityAgricultureSmallSlightOngoing, stableLow
ColumbiaHabitatWater qualityWater Use - temporary diversions/dams, non-consumptiveSmallSlightOngoing, stableLow
ColumbiaHabitatWater qualityWater Use – permanent withdrawal – consumptiveSmallSlightOngoing, stableLow
ColumbiaHabitatWater qualityResidential, Recreational and Commercial DevelopmentSmallSlightOngoing, stableLow
ColumbiaHabitatWater qualityLinear ProjectsSmallSlightOngoing, stableLow
ColumbiaHabitatWater qualityClimate Change & Severe WeatherRestrictedSlightOngoing, increasingLow
ColumbiaHabitatWater qualityOil and GasNegligibleNegligible0Negligible
ColumbiaNon-HabitatAltered community dynamicsInvasive SpeciesSmallUnknownOngoing, stableUnknown
ColumbiaNon-HabitatAltered community dynamicsClimate Change & Severe WeatherUnknownUnknownFuture onlyUnknown
ColumbiaNon-HabitatAltered community dynamicsWater Use – permanent withdrawal – consumptiveRestrictedModerateOngoing, stableLow
ColumbiaNon-HabitatAltered community dynamicsWater Use - temporary diversions/dams, non-consumptivePervasiveSlightOngoing, increasingLow
ColumbiaNon-HabitatAltered community dynamicsResidential, Recreational and Commercial DevelopmentSmallSlightOngoing, stableLow
ColumbiaNon-HabitatAltered community dynamicsIndustrial and Municipal DischargesSmallSlightOngoing, stableLow
ColumbiaNon-HabitatAltered community dynamicsAquaculture, Hatcheries and StockingSmallExtremeOngoing, stableLow
ColumbiaNon-HabitatAltered community dynamicsFishingSmallNegligibleOngoing, stableNegligible
ColumbiaNon-HabitatAltered community dynamicsLinear ProjectsNegligibleNegligible0Negligible
ColumbiaNon-HabitatDirect mortalityResidential, Recreational and Commercial DevelopmentUnknownUnknown0Unknown
ColumbiaNon-HabitatDirect mortalityAquaculture, Hatcheries and StockingRestrictedUnknownOngoing, stableUnknown
ColumbiaNon-HabitatDirect mortalityLinear ProjectsUnknownUnknown0Unknown
ColumbiaNon-HabitatDirect mortalityFishingSmallNegligibleOngoing, stableNegligible
ColumbiaNon-HabitatDiseaseInvasive SpeciesUnknownUnknown0Unknown
ColumbiaNon-HabitatDiseaseIndustrial and Municipal DischargesUnknownUnknown0Unknown
ColumbiaNon-HabitatDiseaseAquaculture, Hatcheries and StockingUnknownUnknown0Unknown
ColumbiaNon-HabitatDiseaseClimate Change & Severe WeatherUnknownUnknownFuture onlyUnknown
ColumbiaNon-HabitatEntrainmentResidential, Recreational and Commercial DevelopmentUnknownUnknown0Unknown
ColumbiaNon-HabitatEntrainmentWater Use - temporary diversions/dams, non-consumptiveNegligibleNegligibleResidual onlyNegligible
ColumbiaNon-HabitatEntrainmentWater Use – permanent withdrawal – consumptiveNegligibleNegligibleOngoing, stableNegligible
ColumbiaNon-HabitatIntrogressionInvasive SpeciesUnknownUnknown0Unknown
ColumbiaNon-HabitatIntrogressionAquaculture, Hatcheries and StockingSmallExtremeOngoing, stableLow
ElkHabitatAltered community dynamicsWater Use - temporary diversions/dams, non-consumptiveSmallUnknownOngoing, increasingUnknown
ElkHabitatAltered community dynamicsClimate Change & Severe WeatherUnknownUnknownFuture onlyUnknown
ElkHabitatAltered community dynamicsWater Use – permanent withdrawal – consumptiveSmallSeriousOngoing, stableLow
ElkHabitatAltered community dynamicsIndustrial and Municipal DischargesSmallSlightOngoing, stableLow
ElkHabitatAltered community dynamicsResidential, Recreational and Commercial DevelopmentSmallSlightOngoing, stableLow
ElkHabitatAltered flow regimeClimate Change & Severe WeatherLargeUnknownOngoing, increasingUnknown
ElkHabitatAltered flow regimeWater Use – permanent withdrawal – consumptiveRestrictedSeriousOngoing, increasingMedium
ElkHabitatAltered flow regimeAgricultureRestrictedModerateOngoing, stableLow
ElkHabitatAltered flow regimeWater Use - temporary diversions/dams, non-consumptiveSmallModerateOngoing, increasingLow
ElkHabitatAltered flow regimeForest HarvestRestrictedModerateOngoing, diminishingLow
ElkHabitatAltered flow regimeIndustrial and Municipal DischargesSmallSlightOngoing, stableLow
ElkHabitatAltered flow regimeMiningSmallSlightOngoing, stableLow
ElkHabitatAltered flow regimeResidential, Recreational and Commercial DevelopmentSmallSlightOngoing, stableLow
ElkHabitatAltered flow regimeOil and GasNegligibleNegligible0Negligible
ElkHabitatAltered flow regimeLinear ProjectsNegligibleNegligible0Negligible
ElkHabitatFish passageForest HarvestRestrictedUnknownOngoing, diminishingUnknown
ElkHabitatFish passageClimate Change & Severe WeatherUnknownUnknownOngoing, stableUnknown
ElkHabitatFish passageWater Use – permanent withdrawal – consumptiveRestrictedSeriousOngoing, increasingMedium
ElkHabitatFish passageLinear ProjectsLargeModerateOngoing, stableMedium
ElkHabitatFish passageWater Use - temporary diversions/dams, non-consumptiveSmallSlightOngoing, increasingLow
ElkHabitatFish passageMiningSmallSlightOngoing, stableLow
ElkHabitatFish passageResidential, Recreational and Commercial DevelopmentSmallSlight0Low
ElkHabitatFish passageOil and GasNegligibleNegligible0Negligible
ElkHabitatInstream mechanical disturbanceAgricultureSmallSeriousOngoing, stableLow
ElkHabitatInstream mechanical disturbanceWater Use – permanent withdrawal – consumptiveRestrictedSlightOngoing, increasingLow
ElkHabitatInstream mechanical disturbanceResidential, Recreational and Commercial DevelopmentSmallSlight0Low
ElkHabitatInstream mechanical disturbanceLinear ProjectsSmallSlightOngoing, stableLow
ElkHabitatInstream mechanical disturbanceWater Use - temporary diversions/dams, non-consumptiveNegligibleSlightOngoing, stableNegligible
ElkHabitatInstream mechanical disturbanceForest HarvestNegligibleNegligibleOngoing, diminishingNegligible
ElkHabitatInstream mechanical disturbanceMiningNegligibleNegligible0Negligible
ElkHabitatLarge scale habitat modificationsAgricultureSmallSlightResidual onlyLow
ElkHabitatLarge scale habitat modificationsMiningSmallSeriousOngoing, stableLow
ElkHabitatLarge scale habitat modificationsResidential, Recreational and Commercial DevelopmentSmallSlightOngoing, increasingLow
ElkHabitatLarge scale habitat modificationsWater Use - temporary diversions/dams, non-consumptiveNegligibleNegligibleOngoing, stableNegligible
ElkHabitatLarge scale habitat modificationsWater Use – permanent withdrawal – consumptiveRestrictedNegligibleOngoing, stableNegligible
ElkHabitatLarge scale habitat modificationsInvasive SpeciesNegligibleNegligible0Negligible
ElkHabitatLarge scale habitat modificationsOil and GasNegligibleNegligible0Negligible
ElkHabitatRiparian clearing and alterationForest HarvestLargeModerateOngoing, stableMedium
ElkHabitatRiparian clearing and alterationMiningRestrictedSeriousOngoing, stableMedium
ElkHabitatRiparian clearing and alterationAgricultureRestrictedSlightOngoing, stableLow
ElkHabitatRiparian clearing and alterationWater Use – permanent withdrawal – consumptiveSmallSlightOngoing, stableLow
ElkHabitatRiparian clearing and alterationResidential, Recreational and Commercial DevelopmentSmallSlightOngoing, increasingLow
ElkHabitatRiparian clearing and alterationLinear ProjectsSmallSlightOngoing, stableLow
ElkHabitatRiparian clearing and alterationWater Use - temporary diversions/dams, non-consumptiveSmallNegligibleOngoing, stableNegligible
ElkHabitatRiparian clearing and alterationOil and GasNegligibleNegligible0Negligible
ElkHabitatSmall scale habitat modificationsInvasive SpeciesRestrictedUnknownFuture onlyUnknown
ElkHabitatSmall scale habitat modificationsAgricultureSmallSlightOngoing, stableLow
ElkHabitatSmall scale habitat modificationsWater Use – permanent withdrawal – consumptiveRestrictedSlightOngoing, stableLow
ElkHabitatSmall scale habitat modificationsMiningSmallModerateOngoing, stableLow
ElkHabitatSmall scale habitat modificationsResidential, Recreational and Commercial DevelopmentSmallSlight0Low
ElkHabitatSmall scale habitat modificationsLinear ProjectsSmallSlightResidual onlyLow
ElkHabitatSmall scale habitat modificationsWater Use - temporary diversions/dams, non-consumptiveSmallNegligibleOngoing, stableNegligible
ElkHabitatSmall scale habitat modificationsOil and GasNegligibleNegligible0Negligible
ElkHabitatWater qualityInvasive SpeciesRestrictedUnknownFuture onlyUnknown
ElkHabitatWater qualityForest HarvestLargeModerateOngoing, increasingMedium
ElkHabitatWater qualityMiningRestrictedSeriousResidual onlyMedium
ElkHabitatWater qualityAgricultureSmallSlightOngoing, stableLow
ElkHabitatWater qualityWater Use - temporary diversions/dams, non-consumptiveSmallSlightOngoing, stableLow
ElkHabitatWater qualityWater Use – permanent withdrawal – consumptiveSmallSlightOngoing, stableLow
ElkHabitatWater qualityResidential, Recreational and Commercial DevelopmentSmallSlightOngoing, stableLow
ElkHabitatWater qualityLinear ProjectsSmallSlightOngoing, stableLow
ElkHabitatWater qualityClimate Change & Severe WeatherRestrictedSlightOngoing, increasingLow
ElkHabitatWater qualityOil and GasNegligibleNegligible0Negligible
ElkNon-HabitatAltered community dynamicsInvasive SpeciesSmallUnknownOngoing, stableUnknown
ElkNon-HabitatAltered community dynamicsClimate Change & Severe WeatherUnknownUnknownFuture onlyUnknown
ElkNon-HabitatAltered community dynamicsWater Use – permanent withdrawal – consumptiveRestrictedModerateOngoing, increasingLow
ElkNon-HabitatAltered community dynamicsAquaculture, Hatcheries and StockingRestrictedSeriousOngoing, stableMedium
ElkNon-HabitatAltered community dynamicsWater Use - temporary diversions/dams, non-consumptiveSmallSlightOngoing, increasingLow
ElkNon-HabitatAltered community dynamicsResidential, Recreational and Commercial DevelopmentSmallSlightOngoing, stableLow
ElkNon-HabitatAltered community dynamicsIndustrial and Municipal DischargesSmallSlightOngoing, stableLow
ElkNon-HabitatAltered community dynamicsFishingLargeNegligibleOngoing, stableNegligible
ElkNon-HabitatAltered community dynamicsLinear ProjectsNegligibleNegligible0Negligible
ElkNon-HabitatDirect mortalityResidential, Recreational and Commercial DevelopmentUnknownUnknown0Unknown
ElkNon-HabitatDirect mortalityAquaculture, Hatcheries and StockingRestrictedUnknownOngoing, stableUnknown
ElkNon-HabitatDirect mortalityLinear ProjectsUnknownUnknown0Unknown
ElkNon-HabitatDirect mortalityFishingLargeSlightOngoing, stableLow
ElkNon-HabitatDiseaseInvasive SpeciesUnknownUnknown0Unknown
ElkNon-HabitatDiseaseIndustrial and Municipal DischargesUnknownUnknown0Unknown
ElkNon-HabitatDiseaseAquaculture, Hatcheries and StockingUnknownUnknown0Unknown
ElkNon-HabitatDiseaseClimate Change & Severe WeatherUnknownUnknownFuture onlyUnknown
ElkNon-HabitatEntrainmentResidential, Recreational and Commercial DevelopmentUnknownUnknown0Unknown
ElkNon-HabitatEntrainmentWater Use - temporary diversions/dams, non-consumptiveNegligibleNegligibleResidual onlyNegligible
ElkNon-HabitatEntrainmentWater Use – permanent withdrawal – consumptiveNegligibleNegligibleOngoing, stableNegligible
ElkNon-HabitatIntrogressionInvasive SpeciesUnknownUnknown0Unknown
ElkNon-HabitatIntrogressionAquaculture, Hatcheries and StockingLargeExtremeOngoing, increasingHigh
FlatheadHabitatAltered community dynamicsClimate Change & Severe WeatherSmallSlightOngoing, increasingLow
FlatheadHabitatAltered community dynamicsWater Use – permanent withdrawal – consumptiveNegligibleNegligible0Negligible
FlatheadHabitatAltered community dynamicsWater Use - temporary diversions/dams, non-consumptiveNegligibleNegligible0Negligible
FlatheadHabitatAltered community dynamicsInvasive SpeciesNegligibleNegligible0Negligible
FlatheadHabitatAltered community dynamicsIndustrial and Municipal DischargesNegligibleNegligible0Negligible
FlatheadHabitatAltered community dynamicsResidential, Recreational and Commercial DevelopmentNegligibleNegligible0Negligible
FlatheadHabitatAltered flow regimeForest HarvestRestrictedModerateOngoing, diminishingLow
FlatheadHabitatAltered flow regimeClimate Change & Severe WeatherRestrictedSlightOngoing, stableLow
FlatheadHabitatAltered flow regimeWater Use – permanent withdrawal – consumptiveNegligibleNegligible0Negligible
FlatheadHabitatAltered flow regimeAgricultureNegligibleNegligible0Negligible
FlatheadHabitatAltered flow regimeWater Use - temporary diversions/dams, non-consumptiveNegligibleNegligible0Negligible
FlatheadHabitatAltered flow regimeIndustrial and Municipal DischargesNegligibleNegligible0Negligible
FlatheadHabitatAltered flow regimeMiningNegligibleNegligible0Negligible
FlatheadHabitatAltered flow regimeOil and GasNegligibleNegligible0Negligible
FlatheadHabitatAltered flow regimeResidential, Recreational and Commercial DevelopmentNegligibleNegligible0Negligible
FlatheadHabitatAltered flow regimeLinear ProjectsNegligibleNegligible0Negligible
FlatheadHabitatFish passageLinear ProjectsUnknownUnknown0Unknown
FlatheadHabitatFish passageForest HarvestRestrictedModerateOngoing, stableLow
FlatheadHabitatFish passageClimate Change & Severe WeatherSmallSlightOngoing, stableLow
FlatheadHabitatFish passageWater Use - temporary diversions/dams, non-consumptiveNegligibleNegligible0Negligible
FlatheadHabitatFish passageWater Use – permanent withdrawal – consumptiveNegligibleNegligible0Negligible
FlatheadHabitatFish passageMiningNegligibleNegligible0Negligible
FlatheadHabitatFish passageOil and GasNegligibleNegligible0Negligible
FlatheadHabitatFish passageResidential, Recreational and Commercial DevelopmentNegligibleNegligible0Negligible
FlatheadHabitatInstream mechanical disturbanceLinear ProjectsRestrictedModerateResidual onlyLow
FlatheadHabitatInstream mechanical disturbanceAgricultureNegligibleNegligibleOngoing, stableNegligible
FlatheadHabitatInstream mechanical disturbanceWater Use - temporary diversions/dams, non-consumptiveNegligibleNegligible0Negligible
FlatheadHabitatInstream mechanical disturbanceWater Use – permanent withdrawal – consumptiveNegligibleNegligible0Negligible
FlatheadHabitatInstream mechanical disturbanceForest HarvestNegligibleNegligibleResidual onlyNegligible
FlatheadHabitatInstream mechanical disturbanceMiningNegligibleNegligible0Negligible
FlatheadHabitatInstream mechanical disturbanceResidential, Recreational and Commercial DevelopmentNegligibleNegligible0Negligible
FlatheadHabitatLarge scale habitat modificationsAgricultureNegligibleNegligible0Negligible
FlatheadHabitatLarge scale habitat modificationsWater Use - temporary diversions/dams, non-consumptiveNegligibleNegligibleOngoing, increasingNegligible
FlatheadHabitatLarge scale habitat modificationsWater Use – permanent withdrawal – consumptiveNegligibleNegligible0Negligible
FlatheadHabitatLarge scale habitat modificationsInvasive SpeciesNegligibleNegligible0Negligible
FlatheadHabitatLarge scale habitat modificationsMiningNegligibleNegligible0Negligible
FlatheadHabitatLarge scale habitat modificationsOil and GasNegligibleNegligible0Negligible
FlatheadHabitatLarge scale habitat modificationsResidential, Recreational and Commercial DevelopmentNegligibleNegligible0Negligible
FlatheadHabitatRiparian clearing and alterationAgricultureSmallSlightOngoing, stableLow
FlatheadHabitatRiparian clearing and alterationForest HarvestRestrictedModerateResidual onlyLow
FlatheadHabitatRiparian clearing and alterationLinear ProjectsRestrictedSlightOngoing, stableLow
FlatheadHabitatRiparian clearing and alterationWater Use - temporary diversions/dams, non-consumptiveNegligibleNegligible0Negligible
FlatheadHabitatRiparian clearing and alterationWater Use – permanent withdrawal – consumptiveNegligibleNegligible0Negligible
FlatheadHabitatRiparian clearing and alterationMiningNegligibleNegligible0Negligible
FlatheadHabitatRiparian clearing and alterationOil and GasNegligibleNegligible0Negligible
FlatheadHabitatRiparian clearing and alterationResidential, Recreational and Commercial DevelopmentNegligibleNegligible0Negligible
FlatheadHabitatSmall scale habitat modificationsInvasive SpeciesUnknownUnknown0Unknown
FlatheadHabitatSmall scale habitat modificationsOil and GasSmallSlightResidual onlyLow
FlatheadHabitatSmall scale habitat modificationsLinear ProjectsSmallSlightOngoing, stableLow
FlatheadHabitatSmall scale habitat modificationsAgricultureNegligibleNegligible0Negligible
FlatheadHabitatSmall scale habitat modificationsWater Use - temporary diversions/dams, non-consumptiveNegligibleNegligible0Negligible
FlatheadHabitatSmall scale habitat modificationsWater Use – permanent withdrawal – consumptiveNegligibleNegligible0Negligible
FlatheadHabitatSmall scale habitat modificationsMiningNegligibleNegligible0Negligible
FlatheadHabitatSmall scale habitat modificationsResidential, Recreational and Commercial DevelopmentNegligibleNegligible0Negligible
FlatheadHabitatWater qualityInvasive SpeciesUnknownUnknown0Unknown
FlatheadHabitatWater qualityAgricultureSmallSlightOngoing, stableLow
FlatheadHabitatWater qualityForest HarvestRestrictedModerateOngoing, diminishingLow
FlatheadHabitatWater qualityOil and GasSmallSlightResidual onlyLow
FlatheadHabitatWater qualityLinear ProjectsRestrictedSlightOngoing, stableLow
FlatheadHabitatWater qualityClimate Change & Severe WeatherSmallSlightOngoing, stableLow
FlatheadHabitatWater qualityWater Use - temporary diversions/dams, non-consumptiveNegligibleNegligible0Negligible
FlatheadHabitatWater qualityWater Use – permanent withdrawal – consumptiveNegligibleNegligible0Negligible
FlatheadHabitatWater qualityMiningNegligibleNegligible0Negligible
FlatheadHabitatWater qualityResidential, Recreational and Commercial DevelopmentNegligibleNegligible0Negligible
FlatheadNon-HabitatAltered community dynamicsLinear ProjectsUnknownUnknown0Unknown
FlatheadNon-HabitatAltered community dynamicsInvasive SpeciesSmallSlightOngoing, stableLow
FlatheadNon-HabitatAltered community dynamicsAquaculture, Hatcheries and StockingRestrictedSlightOngoing, stableLow
FlatheadNon-HabitatAltered community dynamicsClimate Change & Severe WeatherSmallSlightOngoing, stableLow
FlatheadNon-HabitatAltered community dynamicsWater Use – permanent withdrawal – consumptiveNegligibleNegligible0Negligible
FlatheadNon-HabitatAltered community dynamicsWater Use - temporary diversions/dams, non-consumptiveNegligibleNegligible0Negligible
FlatheadNon-HabitatAltered community dynamicsResidential, Recreational and Commercial DevelopmentNegligibleNegligible0Negligible
FlatheadNon-HabitatAltered community dynamicsIndustrial and Municipal DischargesNegligibleNegligible0Negligible
FlatheadNon-HabitatAltered community dynamicsFishingNegligibleNegligible0Negligible
FlatheadNon-HabitatDirect mortalityLinear ProjectsUnknownUnknown0Unknown
FlatheadNon-HabitatDirect mortalityResidential, Recreational and Commercial DevelopmentNegligibleNegligible0Negligible
FlatheadNon-HabitatDirect mortalityFishingSmallNegligibleOngoing, stableNegligible
FlatheadNon-HabitatDirect mortalityAquaculture, Hatcheries and StockingNegligibleNegligibleOngoing, stableNegligible
FlatheadNon-HabitatDiseaseInvasive SpeciesUnknownUnknown0Unknown
FlatheadNon-HabitatDiseaseAquaculture, Hatcheries and StockingUnknownUnknown0Unknown
FlatheadNon-HabitatDiseaseClimate Change & Severe WeatherUnknownUnknown0Unknown
FlatheadNon-HabitatDiseaseIndustrial and Municipal DischargesNegligibleNegligible0Negligible
FlatheadNon-HabitatEntrainmentWater Use - temporary diversions/dams, non-consumptiveNegligibleNegligible0Negligible
FlatheadNon-HabitatEntrainmentWater Use – permanent withdrawal – consumptiveNegligibleNegligible0Negligible
FlatheadNon-HabitatEntrainmentResidential, Recreational and Commercial DevelopmentNegligibleNegligible0Negligible
FlatheadNon-HabitatIntrogressionAquaculture, Hatcheries and StockingUnknownUnknownFuture onlyUnknown
FlatheadNon-HabitatIntrogressionInvasive SpeciesUnknownUnknown0Unknown
Upper KootenayHabitatAltered community dynamicsWater Use - temporary diversions/dams, non-consumptiveSmallUnknownOngoing, increasingUnknown
Upper KootenayHabitatAltered community dynamicsClimate Change & Severe WeatherUnknownUnknownFuture onlyUnknown
Upper KootenayHabitatAltered community dynamicsWater Use – permanent withdrawal – consumptiveSmallSeriousOngoing, stableLow
Upper KootenayHabitatAltered community dynamicsIndustrial and Municipal DischargesSmallSlightOngoing, stableLow
Upper KootenayHabitatAltered community dynamicsResidential, Recreational and Commercial DevelopmentSmallSlightOngoing, stableLow
Upper KootenayHabitatAltered flow regimeClimate Change & Severe WeatherLargeUnknownOngoing, increasingUnknown
Upper KootenayHabitatAltered flow regimeWater Use – permanent withdrawal – consumptiveRestrictedSeriousOngoing, increasingMedium
Upper KootenayHabitatAltered flow regimeAgricultureSmallSlightOngoing, increasingLow
Upper KootenayHabitatAltered flow regimeWater Use - temporary diversions/dams, non-consumptiveSmallModerateOngoing, increasingLow
Upper KootenayHabitatAltered flow regimeForest HarvestRestrictedModerateOngoing, diminishingLow
Upper KootenayHabitatAltered flow regimeIndustrial and Municipal DischargesSmallSlightOngoing, stableLow
Upper KootenayHabitatAltered flow regimeMiningSmallSlightResidual onlyLow
Upper KootenayHabitatAltered flow regimeResidential, Recreational and Commercial DevelopmentSmallSlightOngoing, stableLow
Upper KootenayHabitatAltered flow regimeOil and GasNegligibleNegligible0Negligible
Upper KootenayHabitatAltered flow regimeLinear ProjectsNegligibleNegligible0Negligible
Upper KootenayHabitatFish passageForest HarvestRestrictedUnknownOngoing, diminishingUnknown
Upper KootenayHabitatFish passageClimate Change & Severe WeatherUnknownUnknownOngoing, stableUnknown
Upper KootenayHabitatFish passageWater Use – permanent withdrawal – consumptiveRestrictedSeriousOngoing, increasingMedium
Upper KootenayHabitatFish passageLinear ProjectsLargeModerateOngoing, stableMedium
Upper KootenayHabitatFish passageWater Use - temporary diversions/dams, non-consumptiveSmallSlightOngoing, increasingLow
Upper KootenayHabitatFish passageMiningSmallSlightResidual onlyLow
Upper KootenayHabitatFish passageResidential, Recreational and Commercial DevelopmentSmallSlight0Low
Upper KootenayHabitatFish passageOil and GasNegligibleNegligible0Negligible
Upper KootenayHabitatInstream mechanical disturbanceAgricultureSmallSeriousOngoing, stableLow
Upper KootenayHabitatInstream mechanical disturbanceWater Use – permanent withdrawal – consumptiveRestrictedSlightOngoing, increasingLow
Upper KootenayHabitatInstream mechanical disturbanceResidential, Recreational and Commercial DevelopmentSmallSlight0Low
Upper KootenayHabitatInstream mechanical disturbanceLinear ProjectsSmallSlightOngoing, stableLow
Upper KootenayHabitatInstream mechanical disturbanceWater Use - temporary diversions/dams, non-consumptiveNegligibleSlightOngoing, stableNegligible
Upper KootenayHabitatInstream mechanical disturbanceForest HarvestNegligibleNegligibleOngoing, diminishingNegligible
Upper KootenayHabitatInstream mechanical disturbanceMiningNegligibleNegligible0Negligible
Upper KootenayHabitatLarge scale habitat modificationsAgricultureSmallSlightResidual onlyLow
Upper KootenayHabitatLarge scale habitat modificationsMiningSmallSlightOngoing, stableLow
Upper KootenayHabitatLarge scale habitat modificationsResidential, Recreational and Commercial DevelopmentSmallSlightOngoing, increasingLow
Upper KootenayHabitatLarge scale habitat modificationsWater Use - temporary diversions/dams, non-consumptiveNegligibleNegligibleOngoing, stableNegligible
Upper KootenayHabitatLarge scale habitat modificationsWater Use – permanent withdrawal – consumptiveRestrictedNegligibleOngoing, stableNegligible
Upper KootenayHabitatLarge scale habitat modificationsInvasive SpeciesNegligibleNegligible0Negligible
Upper KootenayHabitatLarge scale habitat modificationsOil and GasNegligibleNegligible0Negligible
Upper KootenayHabitatRiparian clearing and alterationForest HarvestLargeModerateOngoing, stableMedium
Upper KootenayHabitatRiparian clearing and alterationAgricultureRestrictedSlightOngoing, stableLow
Upper KootenayHabitatRiparian clearing and alterationWater Use – permanent withdrawal – consumptiveSmallSlightOngoing, stableLow
Upper KootenayHabitatRiparian clearing and alterationMiningSmallSlightOngoing, stableLow
Upper KootenayHabitatRiparian clearing and alterationResidential, Recreational and Commercial DevelopmentSmallModerateOngoing, increasingLow
Upper KootenayHabitatRiparian clearing and alterationLinear ProjectsSmallSlightOngoing, stableLow
Upper KootenayHabitatRiparian clearing and alterationWater Use - temporary diversions/dams, non-consumptiveSmallNegligibleOngoing, stableNegligible
Upper KootenayHabitatRiparian clearing and alterationOil and GasNegligibleNegligible0Negligible
Upper KootenayHabitatSmall scale habitat modificationsInvasive SpeciesRestrictedUnknownFuture onlyUnknown
Upper KootenayHabitatSmall scale habitat modificationsAgricultureSmallSlightOngoing, stableLow
Upper KootenayHabitatSmall scale habitat modificationsWater Use – permanent withdrawal – consumptiveRestrictedSlightOngoing, stableLow
Upper KootenayHabitatSmall scale habitat modificationsMiningSmallSlightOngoing, stableLow
Upper KootenayHabitatSmall scale habitat modificationsResidential, Recreational and Commercial DevelopmentSmallSlight0Low
Upper KootenayHabitatSmall scale habitat modificationsLinear ProjectsSmallSeriousOngoing, stableLow
Upper KootenayHabitatSmall scale habitat modificationsWater Use - temporary diversions/dams, non-consumptiveSmallNegligibleOngoing, stableNegligible
Upper KootenayHabitatSmall scale habitat modificationsOil and GasNegligibleNegligible0Negligible
Upper KootenayHabitatWater qualityInvasive SpeciesRestrictedUnknownFuture onlyUnknown
Upper KootenayHabitatWater qualityForest HarvestLargeModerateOngoing, stableMedium
Upper KootenayHabitatWater qualityAgricultureSmallSlightOngoing, stableLow
Upper KootenayHabitatWater qualityWater Use - temporary diversions/dams, non-consumptiveSmallSlightOngoing, stableLow
Upper KootenayHabitatWater qualityWater Use – permanent withdrawal – consumptiveSmallSlightOngoing, stableLow
Upper KootenayHabitatWater qualityMiningSmallSlightResidual onlyLow
Upper KootenayHabitatWater qualityResidential, Recreational and Commercial DevelopmentSmallSlightOngoing, stableLow
Upper KootenayHabitatWater qualityLinear ProjectsSmallSlightOngoing, stableLow
Upper KootenayHabitatWater qualityClimate Change & Severe WeatherRestrictedSlightOngoing, increasingLow
Upper KootenayHabitatWater qualityOil and GasNegligibleNegligible0Negligible
Upper KootenayNon-HabitatAltered community dynamicsInvasive SpeciesSmallUnknownOngoing, stableUnknown
Upper KootenayNon-HabitatAltered community dynamicsClimate Change & Severe WeatherUnknownUnknownFuture onlyUnknown
Upper KootenayNon-HabitatAltered community dynamicsAquaculture, Hatcheries and StockingRestrictedExtremeOngoing, stableMedium
Upper KootenayNon-HabitatAltered community dynamicsWater Use – permanent withdrawal – consumptiveRestrictedModerateOngoing, increasingLow
Upper KootenayNon-HabitatAltered community dynamicsWater Use - temporary diversions/dams, non-consumptiveSmallSlightOngoing, increasingLow
Upper KootenayNon-HabitatAltered community dynamicsResidential, Recreational and Commercial DevelopmentSmallSlightOngoing, stableLow
Upper KootenayNon-HabitatAltered community dynamicsIndustrial and Municipal DischargesSmallSlightOngoing, stableLow
Upper KootenayNon-HabitatAltered community dynamicsFishingLargeNegligibleOngoing, stableNegligible
Upper KootenayNon-HabitatAltered community dynamicsLinear ProjectsNegligibleNegligible0Negligible
Upper KootenayNon-HabitatDirect mortalityResidential, Recreational and Commercial DevelopmentUnknownUnknown0Unknown
Upper KootenayNon-HabitatDirect mortalityAquaculture, Hatcheries and StockingRestrictedUnknownOngoing, stableUnknown
Upper KootenayNon-HabitatDirect mortalityLinear ProjectsUnknownUnknown0Unknown
Upper KootenayNon-HabitatDirect mortalityFishingLargeSlightOngoing, stableLow
Upper KootenayNon-HabitatDiseaseInvasive SpeciesUnknownUnknown0Unknown
Upper KootenayNon-HabitatDiseaseIndustrial and Municipal DischargesUnknownUnknown0Unknown
Upper KootenayNon-HabitatDiseaseAquaculture, Hatcheries and StockingUnknownUnknown0Unknown
Upper KootenayNon-HabitatDiseaseClimate Change & Severe WeatherUnknownUnknownFuture onlyUnknown
Upper KootenayNon-HabitatEntrainmentResidential, Recreational and Commercial DevelopmentUnknownUnknown0Unknown
Upper KootenayNon-HabitatEntrainmentWater Use - temporary diversions/dams, non-consumptiveSmallNegligibleResidual onlyNegligible
Upper KootenayNon-HabitatEntrainmentWater Use – permanent withdrawal – consumptiveNegligibleNegligibleOngoing, stableNegligible
Upper KootenayNon-HabitatIntrogressionInvasive SpeciesUnknownUnknown0Unknown
Upper KootenayNon-HabitatIntrogressionAquaculture, Hatcheries and StockingLargeExtremeOngoing, increasingHigh
West KootenayHabitatAltered community dynamicsWater Use – permanent withdrawal – consumptiveLargeModerateOngoing, stableMedium
West KootenayHabitatAltered community dynamicsWater Use - temporary diversions/dams, non-consumptiveRestrictedSlightOngoing, stableLow
West KootenayHabitatAltered community dynamicsInvasive SpeciesRestrictedSlightOngoing, stableLow
West KootenayHabitatAltered community dynamicsIndustrial and Municipal DischargesRestrictedSlightOngoing, stableLow
West KootenayHabitatAltered community dynamicsResidential, Recreational and Commercial DevelopmentRestrictedSlightOngoing, stableLow
West KootenayHabitatAltered community dynamicsClimate Change & Severe WeatherSmallSlightOngoing, increasingLow
West KootenayHabitatAltered flow regimeWater Use – permanent withdrawal – consumptiveLargeModerateOngoing, stableMedium
West KootenayHabitatAltered flow regimeForest HarvestLargeModerateOngoing, diminishingMedium
West KootenayHabitatAltered flow regimeAgricultureSmallModerateOngoing, stableLow
West KootenayHabitatAltered flow regimeWater Use - temporary diversions/dams, non-consumptiveRestrictedModerateOngoing, increasingLow
West KootenayHabitatAltered flow regimeIndustrial and Municipal DischargesSmallSlightOngoing, stableLow
West KootenayHabitatAltered flow regimeMiningRestrictedSlightOngoing, diminishingLow
West KootenayHabitatAltered flow regimeResidential, Recreational and Commercial DevelopmentRestrictedSlightOngoing, stableLow
West KootenayHabitatAltered flow regimeClimate Change & Severe WeatherRestrictedSlightOngoing, stableLow
West KootenayHabitatAltered flow regimeOil and GasNegligibleNegligible0Negligible
West KootenayHabitatAltered flow regimeLinear ProjectsNegligibleNegligible0Negligible
West KootenayHabitatFish passageLinear ProjectsLargeUnknown0Unknown
West KootenayHabitatFish passageWater Use – permanent withdrawal – consumptiveLargeModerateOngoing, stableMedium
West KootenayHabitatFish passageForest HarvestLargeModerateOngoing, stableMedium
West KootenayHabitatFish passageWater Use - temporary diversions/dams, non-consumptiveRestrictedSlight0Low
West KootenayHabitatFish passageMiningRestrictedSlightResidual onlyLow
West KootenayHabitatFish passageResidential, Recreational and Commercial DevelopmentRestrictedSlightOngoing, stableLow
West KootenayHabitatFish passageClimate Change & Severe WeatherSmallSlightOngoing, stableLow
West KootenayHabitatFish passageOil and GasNegligibleNegligible0Negligible
West KootenayHabitatInstream mechanical disturbanceLinear ProjectsLargeModerateOngoing, stableMedium
West KootenayHabitatInstream mechanical disturbanceForest HarvestSmallSlightOngoing, stableLow
West KootenayHabitatInstream mechanical disturbanceAgricultureSmallSlightOngoing, stableLow
West KootenayHabitatInstream mechanical disturbanceWater Use – permanent withdrawal – consumptiveRestrictedSlightOngoing, stableLow
West KootenayHabitatInstream mechanical disturbanceResidential, Recreational and Commercial DevelopmentRestrictedSlightOngoing, stableLow
West KootenayHabitatInstream mechanical disturbanceWater Use - temporary diversions/dams, non-consumptiveSmallNegligibleOngoing, stableNegligible
West KootenayHabitatInstream mechanical disturbanceMiningNegligibleNegligible0Negligible
West KootenayHabitatLarge scale habitat modificationsAgricultureSmallSlightResidual onlyLow
West KootenayHabitatLarge scale habitat modificationsWater Use – permanent withdrawal – consumptiveRestrictedModerateOngoing, stableLow
West KootenayHabitatLarge scale habitat modificationsMiningSmallSlightOngoing, stableLow
West KootenayHabitatLarge scale habitat modificationsResidential, Recreational and Commercial DevelopmentRestrictedSlightOngoing, increasingLow
West KootenayHabitatLarge scale habitat modificationsWater Use - temporary diversions/dams, non-consumptiveRestrictedNegligibleOngoing, stableNegligible
West KootenayHabitatLarge scale habitat modificationsInvasive SpeciesNegligibleNegligible0Negligible
West KootenayHabitatLarge scale habitat modificationsOil and GasNegligibleNegligible0Negligible
West KootenayHabitatRiparian clearing and alterationForest HarvestLargeModerateResidual onlyMedium
West KootenayHabitatRiparian clearing and alterationAgricultureSmallSlightOngoing, stableLow
West KootenayHabitatRiparian clearing and alterationWater Use - temporary diversions/dams, non-consumptiveRestrictedSlightOngoing, stableLow
West KootenayHabitatRiparian clearing and alterationWater Use – permanent withdrawal – consumptiveRestrictedSlightOngoing, stableLow
West KootenayHabitatRiparian clearing and alterationMiningRestrictedSlightOngoing, stableLow
West KootenayHabitatRiparian clearing and alterationResidential, Recreational and Commercial DevelopmentRestrictedSlightOngoing, stableLow
West KootenayHabitatRiparian clearing and alterationLinear ProjectsRestrictedSlightOngoing, stableLow
West KootenayHabitatRiparian clearing and alterationOil and GasNegligibleNegligible0Negligible
West KootenayHabitatSmall scale habitat modificationsAgricultureSmallSlightOngoing, stableLow
West KootenayHabitatSmall scale habitat modificationsWater Use - temporary diversions/dams, non-consumptiveSmallSlightOngoing, stableLow
West KootenayHabitatSmall scale habitat modificationsWater Use – permanent withdrawal – consumptiveRestrictedSlightOngoing, stableLow
West KootenayHabitatSmall scale habitat modificationsMiningRestrictedSlightOngoing, stableLow
West KootenayHabitatSmall scale habitat modificationsResidential, Recreational and Commercial DevelopmentRestrictedSlightOngoing, stableLow
West KootenayHabitatSmall scale habitat modificationsLinear ProjectsRestrictedSlightResidual onlyLow
West KootenayHabitatSmall scale habitat modificationsInvasive SpeciesNegligibleNegligible0Negligible
West KootenayHabitatSmall scale habitat modificationsOil and GasNegligibleNegligible0Negligible
West KootenayHabitatWater qualityForest HarvestLargeModerateOngoing, diminishingMedium
West KootenayHabitatWater qualityAgricultureSmallSlightOngoing, stableLow
West KootenayHabitatWater qualityWater Use - temporary diversions/dams, non-consumptiveRestrictedSlightOngoing, stableLow
West KootenayHabitatWater qualityWater Use – permanent withdrawal – consumptiveRestrictedModerateOngoing, stableLow
West KootenayHabitatWater qualityMiningRestrictedSlightResidual onlyLow
West KootenayHabitatWater qualityResidential, Recreational and Commercial DevelopmentRestrictedSlightOngoing, stableLow
West KootenayHabitatWater qualityLinear ProjectsRestrictedSlightOngoing, stableLow
West KootenayHabitatWater qualityClimate Change & Severe WeatherRestrictedSlightOngoing, increasingLow
West KootenayHabitatWater qualityInvasive SpeciesNegligibleNegligible0Negligible
West KootenayHabitatWater qualityOil and GasNegligibleNegligible0Negligible
West KootenayNon-HabitatAltered community dynamicsWater Use – permanent withdrawal – consumptiveLargeModerateOngoing, stableMedium
West KootenayNon-HabitatAltered community dynamicsWater Use - temporary diversions/dams, non-consumptiveRestrictedSlightOngoing, increasingLow
West KootenayNon-HabitatAltered community dynamicsResidential, Recreational and Commercial DevelopmentRestrictedSlightOngoing, stableLow
West KootenayNon-HabitatAltered community dynamicsIndustrial and Municipal DischargesRestrictedSlightOngoing, stableLow
West KootenayNon-HabitatAltered community dynamicsInvasive SpeciesRestrictedSlightOngoing, stableLow
West KootenayNon-HabitatAltered community dynamicsAquaculture, Hatcheries and StockingRestrictedSlightOngoing, stableLow
West KootenayNon-HabitatAltered community dynamicsClimate Change & Severe WeatherSmallSlightOngoing, stableLow
West KootenayNon-HabitatAltered community dynamicsFishingNegligibleNegligible0Negligible
West KootenayNon-HabitatAltered community dynamicsLinear ProjectsNegligibleNegligible0Negligible
West KootenayNon-HabitatDirect mortalityResidential, Recreational and Commercial DevelopmentUnknownUnknown0Unknown
West KootenayNon-HabitatDirect mortalityLinear ProjectsUnknownUnknown0Unknown
West KootenayNon-HabitatDirect mortalityFishingSmallNegligibleOngoing, stableNegligible
West KootenayNon-HabitatDirect mortalityAquaculture, Hatcheries and StockingNegligibleNegligible0Negligible
West KootenayNon-HabitatDiseaseInvasive SpeciesUnknownUnknown0Unknown
West KootenayNon-HabitatDiseaseIndustrial and Municipal DischargesUnknownUnknown0Unknown
West KootenayNon-HabitatDiseaseAquaculture, Hatcheries and StockingUnknownUnknown0Unknown
West KootenayNon-HabitatDiseaseClimate Change & Severe WeatherUnknownUnknown0Unknown
West KootenayNon-HabitatEntrainmentWater Use - temporary diversions/dams, non-consumptiveNegligibleNegligible0Negligible
West KootenayNon-HabitatEntrainmentWater Use – permanent withdrawal – consumptiveNegligibleNegligible0Negligible
West KootenayNon-HabitatEntrainmentResidential, Recreational and Commercial DevelopmentNegligibleNegligible0Negligible
West KootenayNon-HabitatIntrogressionAquaculture, Hatcheries and StockingUnknownUnknown0Unknown
West KootenayNon-HabitatIntrogressionInvasive SpeciesUnknownUnknown0Unknown

u Population Group – As described inSection 4.2.2.

v Scope – Proportion of the species that can reasonably be expected to be affected by the threat within 10 years. Usually measured as a proportion of the species’ population in the area of interest. (Pervasive = 71–100%; Large = 31–70%; Restricted = 11–30%; Small = 1–10%; Negligible < 1%).

w Severity – the scope, the level of damage to the species from the threat that can reasonably be expected to be affected by the threat within a 10-year or three-generation timeframe. Usually measured as the degree of reduction of the species’ population. (Extreme = 71–100%; Serious = 31–70%; Moderate = 11–30%; Slight = 1–10%; Negligible < 1%).

x Timing – Residual only (i.e., threat is no longer occurring but residual effects continue); Ongoing but diminishing; Ongoing and stable; Ongoing but increasing; and Future only.

y Threat Impact – The degree to which a species is observed, inferred, or suspected to be directly or indirectly threatened in the area of interest (Master et al. 2009). This combined score is based on the interaction between assigned scope and severity values, and considers only present and future threats. Threat impact reflects a reduction of a species population or decline/degradation of the area of an ecosystem. (Very High; High; Medium; Low; Negligible; Unknown; Blank). “Unknown” means that data are not available to assess the threat. Blank means that the assessor cannot make an informed rating.

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22 Recommended management actions for WCT in B.C. were generated largely based on the output of a provincial workshop held in Cranbrook, BC., on December 8–9, 2010.

23 Outputs were generated based on preliminary responses from four local experts, as well as follow-up discussion at the December 2010 provincial workshop.


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