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Recovery Strategy for Paxton Lake, Enos Lake, and Vananda Creek Stickleback Species Pairs (Gasterosteus spp.) in Canada [Final]


Recovery

7. Recovery Goal

The goal of this recovery strategy is to secure the long-term persistence of all extant stickleback species pairs. It is likely that these species will always remain at some risk due to their extremely limited distributions.

8. Recovery Objectives

Short-term (over the next five years):

  1. Maintain self-sustaining populations of stickleback species pairs in Paxton Lake and the Vananda Creek watershed.
  2. Establish captive populations of the Enos Lake species pair.

Long-term (over the next 20 years):

  1. Maintain self-sustaining populations of stickleback species pairs in Paxton Lake and the Vananda Creek watershed.
  2. Establish or recover a viable population of the Enos Lake species pair, preferably in Enos Lake.
  3. Re-establish a stickleback species pair in Hadley Lake from an extant population by restoring Hadley Lake habitat and introducing a species pair from an extant population on Texada Island.

9. Strategies to Address Threats

Strategies identified by the Recovery Team to achieve recovery goals and objectives fall into three broad, complementary categories: stewardship, protection1, and research. These strategies are stated as follows.

  1. Foster awareness of stickleback species pairs (including their unique importance in evolutionary studies, which is recognized internationally), their conservation status and threats to their persistence through direct education and involvement of stakeholders in recovery implementation.
  2. Maintain, and where possible enhance, the ecological integrity of species pair lakes, in particular the habitat features that permit persistence as species pairs.
  3. Increase scientific understanding of stickleback species pairs, the threats to their persistence, and the mechanisms involved in specific threats.

The general approach recommended for undertaking these strategies includes:

  • establishing and supporting stewardship initiatives,
  • undertaking specific research activities to clarify threats,
  • delineation and protection of key habitats,
  • participation in the development and implementation of an exotic species management plan,
  • minimizing impacts from land and water use, and
  • designing and implementing sound monitoring programs.

A description of the recommended approaches and actions is presented in Table 3.

Table 3. Prioritized strategies and recommended actions for the recovery of stickleback species pairs.
Priority2StrategyActionsPerformance
Measure 3
NecessaryEstablish and support Recovery Implementation Groups (RIGs) or alternative working groups for Texada Island and Enos Lake.
  1. Invite stakeholders and interested parties to participate in one or more RIGs. (Due to the geographic separation of species pair lakes it will likely be necessary to establish more than one stewardship group.)
  2. Encourage local governments (e.g., regional districts) to have membership or representation on RIGs to facilitate Recovery Action Plan communication and implementation.
  3. Establish the RIG leadership (chair, facilitator, etc.), develop terms of reference, and obtain necessary funding to support RIG activities.
  4. Develop and implement a Recovery Action Plan, which is to be guided by the Recovery Strategy.
Has a RIG been established for each stickleback species pair?
Are the RIGs adequately supported with funding and technical expertise?
Ha san Action Plan been developed?
Are the RIGs achieving the goals outlined in the Recovery Strategy?
NecessaryEstablish and support a "Research Action Group" to undertake specific research activities and provide detailed technical advice.Invite relevant researchers to participate in a Research Action Group, set terms of reference, and obtain necessary funding.Has a Research Action Group been established?
Is it supported with adequate funding and technical expertise?
Is it meeting the research needs identified in the Recovery Strategy?
NecessaryDevelop and implement an ongoing long-term monitoring program.

RIGs and Research Action Group to develop a monitoring program to assess population response to management activities or threats. Monitoring may include:

  • trends in abundance of each species,
  • trends in habitat quantity and quality,
  • trends in hybridization rates within species pairs' lakes,
  • exotic species distribution and range expansion,
  • water quality,
  • land use, and
  • water use.

RIGs will need to secure long term funding to ensure implementation of an effective monitoring program.
Monitoring priorities will need to be set within the constraints of available budget.

Have monitoring programs been implemented?
How long has a monitoring program been in place?
Is it effective?
Is funding secure for the long term?
NecessarySupport development and implementation of an exotic species management plan with direct links to stewardship groups.

RIGs to work with government agencies to:

  1. develop and implement a comprehensive exotic species management plan.
  2. develop an emergency action plan to implement in case an exotic species is introduced into a species pair lake.
Has an effective exotic species management plan been developed and implemented?
Has an emergency action plan been developed and approved?
Are there resources available to carry it out?
NecessaryDetermine the feasibility of restoring habitat in Enos and Hadley Lakes and introduction species pairs.

Conduct a feasibility study to assess the social and technical issues regarding re-establishing species pairs in Hadley and Enos Lakes. Feasibility may be determined by assessing the following issues:

  1. Determine whether introduced crayfish are responsible for hybridization of stickleback species pairs in Enos Lake.
  2. Investigate the available methods for extirpating exotic species in Enos and Hadley Lakes.
  3. Investigate the ecological requirements for species pairs re-introductions.
  4. Assess social and economic benefits and costs of different scenarios for re-establishing species pairs.
  5. Introduction of sticklebacks to Enos Lake would preferably come from the captive breeding program for the Enos species pair (see additional strategies and approaches below).  Introduction of sticklebacks to Hadley Lake would preferably come from one of the extant pairs on Texada Island.
Has a defensible decision been reached to re-establish a species pair in Enos Lake and/or Hadley Lake?
Has the role of crayfish in hybridization been unambiguously determined?
Is extirpation of exotics feasible and desirable?
Have factors permitting reintroduction of species pairs been unambiguously identified?
PrimaryConduct studies to identify critical habitat for the stickleback species pairs.Undertake necessary research to define critical habitat and to delineate it in the wild. See Section 6.3 for a list of necessary research activities.Has critical habitat been defined for stickleback species pairs?
PrimaryEstablish water quality objectives for all species pair lakes.
  1. Current provincial water quality standards for the protection of aquatic life are appropriate guidelines for basic parameters of water quality in lakes with stickleback species pairs (see http://srmwww.gov.bc.ca/risc/pubs/aquatic/interp/index.htm).
  2. Species-specific water quality objectives may need to be established, particularly with respect to light transmission and nutrient status.
  3. Communicate objectives to appropriate authorities and stakeholders.
Have water quality objectives been established and communicated to relevant regulators and stakeholders?
PrimaryDevelop a comprehensive water management plan for each basin.

RIGs will reduce risk to species pairs by working with Water Stewardship Division (Ministry of Environment) and water licence holders to:

  1. review existing licences
  2. review existing water uses
  3. secure unallocated water for conservation purposes
  4. use a planning process involving stakeholders to establish objectives for present and future water management (e.g., criteria for acceptable levels of water drawdown)
Has a water management plan been completed and implemented?
PrimaryIf re-introduction is feasible, establish a captive breeding program for the Enos Lake species pair.
  1. Capture relic non-hybrid broodstock from Enos Lake, and establish captive populations of both species at UBC.
  2. Invite Research Action Group to review protocols for breeding design (e.g., to prevent loss of genetic variance and minimize adaptation to artificial environments), and obtain necessary funding to support research and population maintenance.
Have captive populations been established for the Enos Lake species pair?
Is the captive population thriving?
Have genetic goals been established for the breeding program and are they being achieved?
Primary

Develop and implement an information and education plan that includes the following elements:

  1. public education material regarding the threat of exotic species
  2. presentation materials for public schools
  3. educational signage for appropriate placement

RIGs to work with government agencies and educators to develop

  1. educational material (e.g., an educational brochure) to explain potential ecological impacts of introducing organisms to new environments.
  2. educational material for use in public schools, particularly schools in the vicinity of the species pairs' lakes. For example, a "Wild BC" module could be prepared and may be widely used.
  3. educational signage for placement at specific locations (e.g., Powell River - Texada Island ferry terminals, at the lakeside of specific lakes, etc.). Obtain funding for sign construction and maintenance.
Have educational materials been produced? Has public perception and awareness been affected?
How many classes have received educational presentations? Has public perception and awareness been affected?
How many educational signs have been erected? Has public perception and awareness been affected?
SecondaryDetermine the potential impacts of recreational fishing in species pair lakes and develop mitigation measures as required.

Work with provincial agencies and the Freshwater Fisheries Society to develop guidelines or regulatory proposals including:

  • no enhancement of recreational fishing through stocking.
  • no fishing on lakes where sport species are not indigenous.
  • no bait where sport fisheries are allowed.

 
Consult on the rationale for the approach with stakeholders and consider additional measures that either limit impacts or support existing fisheries.

Are the minimal regulatory changes implemented?
SecondaryInvestigate potential water quality implications from use of explosives for mining activities within species pairs' watersheds.Review and summarize current or planned mining activities and reassess this threat. If relevant, RIGs to review relevant literature and conduct water quality testing. RIGs to work with Research Action Group as necessary on technical issues. Communicate results for consideration during future review of the Recovery Strategy. Obtain necessary funding to support review, sampling and analysis.Has a literature review been conducted and communicated to the Recovery Team?
Have water quality samples been taken of runoff from mining sites?
Have the samples been analyzed and results effectively communicated?
SecondaryDetermine potential impacts of gas operated motor boats on water quality in the species pair lakes and develop mitigation measures as required, and discourage impacts from lakeshore development and recreational use.RIGs to work with local government and stakeholders to establish designations of no motor or electric motor only on species pair lakes. Note: Canadian Coast Guard is the regulator.Are gas powered boat motors allowed on species pairs' lakes?
SecondaryJointly develop land management strategies for crown and private lands.

Develop criteria for assessing effects of land developments (including forest harvest) on stickleback, develop guidelines for good stewardship, establish Wildlife Habitat Areas (WHAs) where appropriate, and establish species pair watersheds as Special Development Areas.

  1. For crown lands, establish one or more Wildlife Habitat Areas to minimize cumulative long-term habitat impacts.
  2. For private lands, work with land owners to encourage good stewardship.
Have forest harvest and land management criteria been developed?
Have WHAs been established?
Is forest harvest and land development meeting the criteria?
SecondaryDevelop sound protocols for scientific investigations (e.g., limit use of hybrids in in situ experiments, limit number of fish collected each year, etc.)Research Action Group to work with government agencies to set boundaries for experimental work in species pair lakes. Note: SARA permits may be required to legally collect and undertake research on a listed wildlife species.Have scientific investigation protocols been set and communicated?
Have they been implemented?

10. Anticipated Conflicts or Challenges

Stickleback species pairs are currently of little or no economic value, and this is unlikely to change. By contrast there are other public, private and commercial interests in watersheds in which the species pairs reside. These interests include mining, forestry, water extraction for industrial and residential use, roads, pipelines, residential property development, and low-level (at present) recreational use for fishing, boating, and swimming. It is important to understand that many of the threats to species pairs can be reduced but not eliminated.

11. Recovery Feasibility

As part of the SARA process, the competent minister must determine the feasibility of recovery for species at risk. To help standardize these determinations, current draft policy (Government of Canada 2005) poses four questions, which are to be addressed in each recovery strategy. These questions are posed and answered here.

  • Are individuals capable of reproduction currently available to improve the population growth rate or population abundance?
    Yes. Stickleback species pairs naturally have a very restricted distribution. The species pairs on Texada Island are self-supporting with healthy abundance levels and are not in apparent decline (but will continue to be at risk due to their limited geographic range). The Enos Lake species pair has collapsed to a hybrid swarm, but a self-supporting population of Enos Lake limnetics exists in Murdo-Fraser in North Vancouver, and efforts to establish a self-supporting population of Enos Lake benthics are underway and appear to be successful. The Hadley Lake species pair is extinct and recovery of these two species is therefore not feasible.

  • Is sufficient suitable habitat available to support the species or could it be made available through habitat management or restoration?
    Yes. Sufficient suitable habitat exists on Texada Island to support Paxton Lake and Vananda Creek species pairs in their natural habitats. Feasibility of restoring habitats in Hadley Lake is dependent on extirpation of brown bullhead and may require the removal of crayfish in Enos Lake, both of which were introduced to the lakes. Feasibility of habitat restoration and re-introduction of stickleback species pairs to these lakes is currently under study.

  • Can significant threats to the species or its habitat be avoided or mitigated through recovery actions?
    Yes. Controlling threats to the species pairs is feasible, but rests more on social than technical considerations. For example, the primary threat is from the introduction of exotic species. Exotic fish species are spread by unauthorized introductions, and would be best prevented by educating the public about the risks associated with intentionally spreading organisms. Such a program is expected to be beneficial, but its efficacy is nevertheless likely to be less than 100%. Most other threats, such as those from excessive water use, can be managed with existing regulations, but will require consultation with stakeholders.

  • Do the necessary recovery techniques exist and are they demonstrated to be effective?
    Yes. Special recovery techniques are not required for recovery of stickleback species pairs on Texada Island. What is required is effective management of current and future threats, which is believed to be entirely feasible. It should be noted however that stickleback species pairs will likely always be very restricted in their distribution even if they are successfully introduced to fishless lakes in the region. As a result, they are likely to remain at some risk. Recovery efforts for species pairs as a group are best concentrated on controlling threats, and if possible re-introducing the pairs to their original habitats (i.e., Hadley Lake and Enos Lake).

The feasibility of re-introducing the pairs to their original habitats depends on two main technical factors: removing exotic species, and introducing (or re-introducing) species to a lake with no stickleback. Both have significant technical challenges. Overcoming these challenges will require additional research, which is currently underway (see Section 13).

Based on the assessment above, recovery of the stickleback species pairs is determined to be both technically and biologically feasible.

12. Recommended Approach / Scale for Recovery

The recovery strategy for stickleback species pairs recommends the use of a modified single species approach (rather than an ecosystem approach) because the ecology of the species pairs is common across watersheds and the threats to each species pair are similar. Introduction of exotic species and effects of water management and land-based development are seen as the main threats to extant wild populations.

There are few apparent opportunities to combine recovery efforts for stickleback species pairs with existing management plans, actions, or policies. One of the greatest opportunities for conservation of stickleback species pairs would be to participate in the development and execution of a regional exotic species management plan.

13. Knowledge Gaps

We know a great deal about the evolution of the species pairs, but remarkably little about their basic ecology, particularly during early life stages. If the species pairs are to be re-introduced to Hadley and Enos Lakes (or introduced to other lakes) as part of the recovery process, there are good reasons to develop a greater understanding of the basic ecology of the species and their native lakes.

The following are a series of topics that highlight knowledge gaps affecting management of the species pairs. Additional topics will require work if critical habitat is to be well-defined (see Section 6.3).

Basic Biology

  • Define critical habitat for species pairs, and how it can be protected
  • Habitat use during early life stages
  • Age structure of populations
  • Abundance trends (among seasons and years) of limnetics and benthics within each lake
  • Habitat factors required to maintain species segregation
  • Hybridization trends within each lake
  • Hybridization rates in undisturbed conditions
  • Hybridization thresholds in relation to species pair collapse

Threat Clarification

  • Regional trends in the spread of exotic species
  • Relative severity of exotic species introductions (e.g., should some exotic species be targeted for special attention?)
  • Effects of changes in water quality on stickleback species pairs
  • Relationship between water use and risk to stickleback
  • Assess the types and extent of land use activities that can be safely permitted within these watersheds

Rebuilding Techniques

  • Exotic species (e.g., brown bullhead and crayfish) removal techniques
  • Understand the ecological preconditions for maintenance of the species pairs and why pairs collapsed in experimental ponds

Effectiveness of Stewardship

  • Understand the effectiveness of stewardship initiatives (e.g., education programs, signage, angler education)

14. Potential Management Impacts for Other Species

Management actions implemented to mitigate threats to species pairs are unlikely to negatively affect other indigenous species since other species that are known to co-exist with species pairs are widely distributed.

15. Actions Already Completed and/or Underway

A variety of recovery actions have been completed or initiated.

  1. A “Research Action Group” was established in 2003, made up primarily of researchers from UBC.
  2. A wide variety of scientific investigations have been completed or continue to occur:
    1. monitoring of the status of species pairs (this was done in an ad hoc manner in the past, but has recently become somewhat more formalized)
    2. laboratory husbandry techniques are now well worked out.
    3. translocation to experimental ponds (early experiments in experimental ponds have indicated some of the difficulties associated with translocation)
    4. genetics research (microsatellite work continues to be conducted)
    5. ecological and evolutionary research (feeding efficiency experiments, behaviour, mate choice, morphometrics)
    6. scientific documents and publications (there is a long list of primary research publications, primarily completed by researchers at UBC)
  3. Prior to the collapse of the Enos Lake stickleback species pair, a population of Enos Lake limnetics was established by adding wild fish in 1988 and 1999 (under permit from the Fisheries Branch of the British Columbia Ministry of Environment, Lands and Parks) to a pond in Murdo-Frazer Park in North Vancouver. A viable population was confirmed in spring 2002 (D. Schluter, unpublished data).
  4. A program was initiated in 2003 to establish brood stock for future recovery of the Enos Lake species, by capturing putative "pure" benthics and breeding them in the lab. Genetic and morphological testing is underway to confirm identity of individuals used as breeding stock.
  5. Public awareness and education (e.g., publication of a Stickleback Species Pair brochure in the Wildlife in British Columbia at Risk series; "Evolution in Action," a program for Knowledge Network)

16. Statement of when Action Plans will be Completed

Within two years of posting the final recovery strategy, one or more action plans will be developed. The plans will include descriptions of programs, plus a timeline of programs with estimated budgets, and will encompass a timeframe of at least five years.


1 Protection can be achieved through a variety of mechanisms including: voluntary stewardship agreements, conservation covenants, sale by willing vendors on private lands, land use designations, and protected areas.

2 Priority has been assigned based on professional judgement into one of three groups, from highest to lowest: necessary, primary, secondary.

3 Performance measures plot the progress toward meeting the stated objectives. The performance measures are presented here as questions, the answers to which can be plotted in time to monitor progress.