Recovery Strategy for the Coastal Giant Salamander (Dicamptodon tenebrosus) in British Columbia [Proposed] - 2017

• Table of contents
• Document information
• Part 1
• Part 2

• Part 1 - Federal Addition to the Recovery Strategy for the Coastal Giant Salamander (Dicamptodon tenebrosus) in British Columbia
  • Table of contents
  • Preface
  • Acknowledgements
  • Additions and modifications to the adopted document
• 1 COSEWIC species assessment information
• 2 Species status information
• 3 Threats
  • 3.1 Threat assessment
  • 3.2 Description of threats
• 4 Population and distribution objectives
• 5 Broad strategies and general approaches to meet objectives
• 6 Critical habitat
  • 6.1 Identification of the species’ critical habitat
  • 6.2 Schedule of studies to identify critical habitat
  • 6.3 Activities likely to result in destruction of critical habitat
• 7 Measuring progress
• 8 Statement on action plans
• 9 Effects on the environment and other species
• 10 References

• Figure 1. Schematic of methodology used to derive the area(s) containing critical habitat for the Coastal Giant Salamander.
• Figure 2. Critical habitat for the Coastal Giant Salamander in the Chilliwack River area (west), B.C.
• Figure 3. Critical habitat for the Coastal Giant Salamander in the Chilliwack River area (northwest), B.C.
• Figure 4. Critical habitat for the Coastal Giant Salamander in the Chilliwack River area (southwest), B.C.
• Figure 5. Critical habitat for the Coastal Giant Salamander in the Chilliwack River area (north), B.C.
• Figure 6. Critical habitat for the Coastal Giant Salamander in the Chilliwack River area (northeast), B.C.
• Figure 7. Critical habitat for the Coastal Giant Salamander in the Chilliwack River area (southeast), B.C..
• Figure 8. Critical habitat for the Coastal Giant Salamander in the Chilliwack River area (east), B.C.

• Table 1. Conservation Status of the Coastal Giant Salamander (from NatureServe 2016 and B.C. Conservation Framework 2016).
• Table 2. IUCN-CMP threats classification for Coastal Giant Salamander in Canada.
• Table 3. Summary of essential functions, biophysical features, and general attributes of Coastal Giant Salamander core critical habitat.
• Table 4. Summary of essential functions, biophysical features, and general attributes of Coastal Giant Salamander connective critical habitat.
• Table 5. Schedule of Studies to Identify Critical Habitat for the Coastal Giant Salamander.
• Table 6. Activities likely to result in destruction of critical habitat for the Coastal Giant Salamander.

• Part 2 - Recovery Strategy for the Pacific Giant Salamander (Dicamptodon tenebrosus) in British Columbia prepared by the Pacific Giant Salamander Recovery Team for the British Columbia Ministry of Environment
  • Table of contents
    • Recovery team members
    • Responsible jurisdictions
    • Acknowledgements
    • Executive summary
  • Background
    • Species assessment information from COSEWIC
    • Description of the species
    • Populations and distribution
    • Needs of the pacific giant salamander
      • Habitat and biological needs
        • General habitat associates
        • Habitat requirements at different life stages
        • Reproductive stage
        • Aquatic larvae
        • Terrestrial phase
        • Neotenic phase
      • Movement and dispersal
      • Ecological role
      • Limiting factors
        • Limited dispersal ability
        • Complex life history and restricted habitat requirements
        • Low reproductive potential
        • Vulnerability of peripheral populations
    • Threats
      • Threat classification
      • Description of the threats
        • Forestry activities
        • Urban and rural development
        • Micro-hydro developments
        • Pollution
        • Climate change
        • Disease
        • Introduced fish
        • Recreational activities
    • Actions already completed or underway
    • Knowledge gaps
  • Recovery
    • Recovery feasibility
    • Recovery goal
    • Rationale for the recovery goal
    • Recovery objectives (2009-2013)
    • Approaches recommended to meet recovery objectives
      • Recovery planning table
      • Description of the recovery planning table
        • Habitat protection, management, and stewardship
        • Habitat mapping
        • Population inventories
        • Habitat restoration
        • Population and habitat monitoring
        • Threat clarification
        • Research on life history, population dynamics, and habitat use
        • Outreach and communication
    • Performance measures
    • Critical habitat
      • Identification of the species' critical habitat
        • Biophysical attributes of critical habitat
    • Recommended schedule of studies to identify critical habitat
    • Existing and recommended approaches to habitat protection
    • Effects on other species
    • Socioeconomic considerations
    • Recommended approach for recovery implementation
    • Statement on action plans
  • References

• Figure 1. Global distribution of the Pacific Giant Salamander, Dicamptodon tenebrosus. Prepared by H. Welsh for Field Guide to the Amphibians of Northwestern North America (Jones and Leonard [eds.] 2005).
• Figure 2. Distribution of the Pacific Giant Salamander, Dicamptodon tenebrosus, in British Columbia.
• Figure 3. Map of existing habitat protection for Pacific Giant Salamanders in B.C.

• Table 1. Conservation status of the Pacific Giant Salamander (B.C. Conservation Data Centre 2009; NatureServe 2009).
• Table 2. Threat classification table for the pacific giant salamander.
  • Table 2.1 Forestry activities affecting aquatic habitat
  • Table 2.2 Forestry activities affecting terrestrial habitat
  • Table 2.3 Urban and rural development
  • Table 2.4 Micro-hydro developments
  • Table 2.5 Pollution
  • Table 2.6 Climate change
  • Table 2.7 Disease
  • Table 2.8 Introduced fish
  • Table 2.9 Recreational activities
• Table 3. Recovery strategies for the Pacific Giant Salamander.
• Table 4. Schedule of studies for identifying critical habitat.

• Appendix 1. Acronyms and definitions of terms
• Appendix 2. Stream ordering system
• Appendix 3. Approved wildlife habitat areas (as of january 2010)
  • Area of each WHA for Pacific Giant Salamander
  • Total area (ha) of WHAs
  • Length of WHAs for Pacific Giant Salamander
• Appendix 4. Design and effectiveness of forested buffers and reserves

For copies of the recovery strategy, or for additional information on species at risk, including the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) Status Reports, residence descriptions, action plans, and other related recovery documents, please visit the Species at Risk (SAR) Public Registry.

Cover illustration: © Corel Corporation

Également disponible en français sous le titre

« Programme de rétablissement de la grande salamandre (Dicamptodon tenebrosus) au Canada [Proposition] »

Content (excluding the illustrations) may be used without permission, with appropriate credit to the source.

The federal recovery strategy for the Coastal Giant Salamander in Canada consists of two parts:

Part 1 - Federal addition to the Recovery Strategy for the Coastal Giant Salamander (Dicamptodon tenebrosus) in British Columbia, prepared by Environment and Climate Change Canada.

Part 2 - Recovery Strategy for the Pacific Giant Salamander (Dicamptodon tenebrosus) in British Columbia, prepared by the Pacific Giant Salamander Recovery Team for the British Columbia Ministry of Environment.

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

The Minister of Environment and Climate Change is the competent minister under SARA for the Coastal Giant Salamander and has prepared the federal component of this recovery strategy (Part 1), as per section 37 of SARA. To the extent possible, it has been prepared in cooperation with the Province of British Columbia as per section 39(1) of SARA. SARA section 44 allows the Minister to adopt all or part of an existing plan for the species if it meets the requirements under SARA for content (sub-sections 41(1) or (2)). The Province of British Columbia provided the attached recovery strategy for the Coastal Giant Salamander (Part 2) as science advice to the jurisdictions responsible for managing the species in British Columbia. It was prepared in cooperation with Environment and Climate Change Canada.

Success in the recovery of this species depends on the commitment and cooperation of many different constituencies that will be involved in implementing the directions set out in this strategy and will not be achieved by Environment and Climate Change Canada, or any other jurisdiction alone. All Canadians are invited to join in supporting and implementing this strategy for the benefit of the Coastal Giant Salamander and Canadian society as a whole.

This recovery strategy will be followed by one or more action plans that will provide information on recovery measures to be taken by Environment and Climate Change Canada and other jurisdictions and/or organizations involved in the conservation of the species. Implementation of this strategy is subject to appropriations, priorities, and budgetary constraints of the participating jurisdictions and organizations.

The recovery strategy sets the strategic direction to arrest or reverse the decline of the species, including identification of critical habitat to the extent possible. It provides all Canadians with information to help take action on species conservation. When critical habitat is identified, either in a recovery strategy or an action plan, SARA requires that critical habitat then be protected.

In the case of critical habitat identified for terrestrial species including migratory birds SARA requires that critical habitat identified in a federally protected area ^Footnote1 be described in the Canada Gazette within 90 days after the recovery strategy or action plan that identified the critical habitat is included in the public registry. A prohibition against destruction of critical habitat under ss. 58(1) will apply 90 days after the description of the critical habitat is published in the Canada Gazette .

For critical habitat located on other federal lands, the competent minister must either make a statement on existing legal protection or make an order so that the prohibition against destruction of critical habitat applies.

If the critical habitat for a migratory bird is not within a federal protected area and is not on federal land, within the exclusive economic zone or on the continental shelf of Canada, the prohibition against destruction can only apply to those portions of the critical habitat that are habitat to which the Migratory Birds Convention Act, 1994 applies as per SARA ss. 58(5.1) and ss. 58(5.2).

For any part of critical habitat located on non-federal lands, if the competent minister forms the opinion that any portion of critical habitat is not protected by provisions in or measures under SARA or other Acts of Parliament, or the laws of the province or territory, SARA requires that the Minister recommend that the Governor in Council make an order to prohibit destruction of critical habitat. The discretion to protect critical habitat on non-federal lands that is not otherwise protected rests with the Governor in Council.

Development of this recovery strategy was coordinated by Environment and Climate Change Canada, Canadian Wildlife Service (ECCC CWS) – Pacific Region staff: Matt Huntley, Kella Sadler, Lisa Rockwell, and Megan Harrison. Elke Wind (E.Wind Consulting) compiled information for the initial draft of this recovery strategy. Kym Welstead (B.C. Forests, Lands and Natural Resource Operations), Purnima Govindarajulu and Peter Fielder (B.C. Ministry of Environment), Dave Trotter (B.C. Ministry of Agriculture), and Véronique Brondex (ECCC CWS-National Capital Region) provided helpful editorial advice and comment. Kym Welstead also provided supporting data and background documents. Jeffrey Thomas and Danielle Yu (ECCC CWS-Pacific Region) provided additional assistance with mapping and figure preparation.

The following sections have been included to address specific requirements of the federal Species at Risk Act (SARA) that are not addressed in the Recovery Strategy for the Pacific Giant Salamander (Dicamptodon tenebrosus) in British Columbia (Part 2 of this document, referred to henceforth as “the provincial recovery strategy”), and/or to provide updated or additional information.

Under SARA, there are specific requirements and processes set out regarding the protection of critical habitat. Therefore, statements in the provincial recovery strategy referring to protection of survival/recovery habitat may not directly correspond to federal requirements. Recovery measures dealing with the protection of habitat are adopted; however, whether these measures will result in protection of critical habitat under SARA will be assessed following publication of the final federal recovery strategy.

The provincial recovery strategy contains a short statement on socio-economic considerations. As a socio-economic analysis is not required under Section 41(1) of SARA, the “Socio-economic Considerations” section of the provincial recovery strategy is not considered part of the federal Minister of Environment and Climate Change's recovery strategy for this species.

This section replaces the “Species Assessment Information from COSEWIC” section in the provincial recovery strategy to incorporate the most recent information from COSEWIC (2014).

ⁱ COSEWIC (Committee on the Status of Endangered Wildlife in Canada)

Legal Designation: SARA Schedule 1 (Threatened) (2003).

^a The conservation status of a species is designated by a number from 1 to 5, preceded by a letter reflecting the appropriate geographic scale of the assessment (G = Global, N = National, and S = Subnational). The numbers have the following meaning: 1 = critically imperiled, 2 = imperiled, 3 = vulnerable, 4 = apparently secure, 5 = secure. X = Presumed Extirpated, NR = Unranked.

^b The three goals of the B.C. Conservation Framework are: 1. Contribute to global efforts for species and ecosystem conservation; 2. Prevent species and ecosystems from becoming at risk; 3. Maintain the diversity of native species and ecosystems

It is estimated that the percent of the global range and population of this species in Canada is less than 1% (COSEWIC 2014).

Table 2 (below) replaces and updates Table 2 of the “Threats Classification” section in the provincial recovery strategy.

The updated threat classification table incorporates the most recent information from COSEWIC (2014) and is based on the IUCN-CMP (International Union for Conservation of Nature–Conservation Measures Partnership) unified threats classification system (CMP 2010). It is consistent with methods used by the B.C. Conservation Data Centre and the B.C. Conservation Framework.

Threats are defined as the proximate activities or processes that have caused, are causing, or may cause in the future the destruction, degradation, and/or impairment of the entity being assessed (population, species, community, or ecosystem) in the area of interest (global, national, or subnational). Limiting factors are not considered during this assessment process. For purposes of threat assessment, only present and future threats are considered. Historical threats, indirect or cumulative effects of the threats, or any other relevant information that would help understand the nature of the threats are presented in the Description of Threats section. Threats are characterized in terms of scope, severity, and timing. Threat "impact" is calculated from scope and severity.

^c Impact – The degree to which a species is observed, inferred, or suspected to be directly or indirectly threatened in the area of interest. The impact of each stress is based on Severity and Scope rating 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. The median rate of population reduction or area decline for each combination of scope and severity corresponds to the following classes of threat impact: very high (75% declines), high (40%), medium (15%), and low (3%). Unknown: used when the impact cannot be determined (e.g., if values for either scope or severity are unknown); Not Calculated: impact not calculated as threat is outside the assessment timeframe (e.g., timing is insignificant/negligible or low as threat is only considered to be in the past); Negligible: when scope or severity is negligible; Not a Threat: when severity is scored as neutral or potential benefit.

^d 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%).

^e Severity – Within 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%) .

^f Timing – High = continuing; Moderate = only in the future (could happen in the short term [< 10 years or 3 generations]) or now suspended (could come back in the short term); Low = only in the future (could happen in the long term) or now suspended (could come back in the long term); Insignificant/Negligible = only in the past and unlikely to return, or no direct effect but limiting.

The calculated overall threat impact ^Footnote2 to the Coastal Giant Salamander is High. Threat descriptions are consistent with those provided in the provincial recovery strategy (i.e., “Description of the threats” section), although content information has been reorganized owing the fact that the IUCN-CMP threats classification was not used in that document. Where appropriate, updated information on threat descriptions has been added or adapted from the COSEWIC status report (COSEWIC 2014). Currently the primary threats are logging and wood harvesting (Threat #5.3), and agricultural and forestry effluents (Threat #9.3). Secondary threats include: Housing and urban areas (Threat #1.1), Tourism and recreation areas (Threat #1.3), Mining and quarrying (Threat #3.2), Transportation and service corridors (Threat #4), Recreational activities (Threat #6.1), Dams and water management/use (Threat #7.2), Invasive non-native/alien species (Threat #8.1), Household sewage and urban waste water (Threat #9.1) and Climate change and severe weather (#11). All other threats are currently of negligible impact.

IUCN-CMP Threat #1: Residential & commercial development

1.1 Housing & urban areas (Low impact), 1.2 Commercial & industrial areas (Negligible impact) and 1.3 Tourism & recreation areas (Low impact)

A description of this threat is available in the adopted provincial recovery strategy (“Urban and rural development” subsection).

IUCN-CMP Threat #2: Agriculture & Aquaculture

2.1 Annual & perennial non-timber crops (Negligible impact) and 2.3 Livestock farming & ranching (Negligible impact)

Most agricultural development in lower elevation areas is historical and this threat largely applies to new potential greenhouse or plant nursery developments. While new

developments can lead to loss, fragmentation, or degradation of habitat, this threat is not likely to have substantial impacts as any new development is most likely to occur in areas less occupied by the Coastal Giant Salamander (i.e. lower elevation valley bottoms). Additionally, there are dairy farms which occur along the Chilliwack River, which may pose a habitat degradation threat to riparian areas should livestock-use intensify. Both of these threats are deemed negligible due to the limited scope within Coastal Giant Salamander habitat.

IUCN-CMP Threat #3: Energy Production & Mining

3.2 Mining & Quarrying (Low impact)

Current mining from the watershed is primarily for the extraction of sand and gravel resources. As of 2012, there were 7 active permits with sand and gravel operations either proposed or in progress in the Chilliwack Valley (COSEWIC 2014). Mining and quarrying operations can cause aquatic and riparian habitat loss and degradation.

IUCN-CMP Threat #4: Transportation & Service Corridors

4.1 Roads & Railroads (Low impact) and 4.2 Utility and Service Lines (Low impact)

Resource roads used by the forestry, mining, and renewable energy sectors are prevalent within the range of the Coastal Giant Salamander and are primarily associated with timber harvesting (COSEWIC 2014). The habitat degradation impacts are greatest during the construction of new roads which can involve vegetation clearing and soil disturbance leading to terrestrial habitat loss, and instream works for culvert and bridge installations leading to aquatic habitat loss from altering stream flows and increasing sedimentation of streams (see Threat # 9 Pollution below).

Additionally, roads and other linear developments can fragment forest habitats and interfere with movement and dispersal of adult and juvenile Coastal Giant Salamanders. Threat severity is expected to be slight as the majority of roads occur in upslope habitats which are less occupied by the Coastal Giant Salamander (i.e., not near and parallel to watercourses).

IUCN-CMP Threat # 5 Biological resource use

5.3 Logging & wood harvesting (Medium impact)

A description of this threat is available in the adopted provincial recovery strategy (“Forestry activities” subsection).

IUCN-CMP Threat # 6 Human intrusions & disturbance

6.1 Recreational activities (Low impact)

A description of this threat is available in the adopted provincial recovery strategy (“Recreational activities” subsection).

IUCN-CMP Threat # 7 Natural system modifications

7.2 Dams & water management/use (Low impact)

A description of this threat is available in the adopted provincial recovery strategy (“Micro-hydro developments” subsection).

IUCN-CMP Threat # 8 Invasive & other problematic species & genes

8.1 Invasive non-native/alien species (Low impact)

The introduction of predatory fish (i.e. stocking of sport fish) to historically unoccupied waterways is a threat to Coastal Giant Salamanders as salmonids are routinely stocked within the Chilliwack drainage (COSEWIC 2014). Predatory fish may prey upon smaller larvae (Rundio et al. 2003) which may also limit dispersal among sub-drainages connected by larger water bodies, increase competition for food resources in occupied streams, or increase the risk of introducing epidemic diseases which may be transmitted from fish to amphibians such as the water mold Saprolegnia ferax (Romansic et al. 2009) or various iridoviruses (Daszak et al. 1999; Mao et al. 1999).

Little is known about the vulnerability of Coastal Giant Salamanders to epidemic diseases, but increased access to headwater streams, through forestry roads and recreational trails, may result in the introduction or spread of infectious diseases to salamander populations. Of immediate concern is the pathogenic chytrid fungus Batrachochytrium dendrobatidis, which is already prevalent in B.C. (Govindarajulu et al. 2013), and has been implicated in amphibian declines in the western United States and globally (Daszak et al. 1999). A study of stream associated amphibians in mountainous areas of the U.S. by Hossack et al (2010) describe low detection rates (0.93%) for B.dendrobatidis from 452 tailed frogs and 304 stream salamanders. The authors suggest that temperate stream-dwelling amphibians may be less susceptible to chytridiomycosis caused by B.dendrobatidis due to extended seasonal periods of low water temperature which may inhibit the growth of the fungus, though early investigations do not entirely support this (Knapp et al. 2011).

An emerging potential threat, is the recently described chytrid fungus, Batrachochytrium salamandrivorans, that has caused recent salamander die-offs in parts of Europe (Martel et al. 2013). While B.salamandrivorans has not yet been reported from North America, it operates at lower temperatures than B.dendrobatidis and could therefore be a significant threat to the Coastal Giant Salamander, and other salamanders occupying cool stream habitats, should it be introduced to North America.

IUCN-CMP Threat # 9 Pollution

9.3 Agricultural & forestry effluents (Medium-Low impact) and 9.1 Household sewage & urban waste water (Low impact)

A description of this threat is inserted from COSEWIC (2014):

Roads and trails can be a source of pollutants from sediments and chemical use. Sediments may also enter the system via slope failures from forestry operations, clearcutting activities upstream, or development projects, such as run-of-river power projects. Numerous studies in the United States have found that stream sedimentation is detrimental to Coastal Giant Salamanders (Hall et al. 1978; Hawkins et al. 1983; Corn and Bury 1989; Welsh and Ollivier 1998; Ashton et al. 2006). Fine sediments fill in interstitial spaces among rocks with the stream substrate, so reducing or eliminating refuges that are critical for salamander larvae. In the Chilliwack Valley, preliminary results from data collected by BCIT students’ studies suggest that logging can result in sedimentation of stream stretches occupied by Coastal Salamanders, even where forested riparian buffers of 30 – 50 m are left within Wildlife Habitat Areas for the species (Welstead pers. comm. 2013). Anecdotally, fewer salamanders have been observed in streams and pools with relatively high silt content in the Chilliwack area (Knopp pers. comm. 2012).

Roads are also a source of chemical inputs into streams. For example, chemicals used to reduce road dust and to de-ice roads may impact Coastal Giant Salamanders. Impacts from chemical use depend on how much the chemicals are diluted within the system, for example through rain, and the extent of their use at any given time.

Herbicides used in housing developments, commercial areas, and in forestry may pose a threat to Coastal Giant Salamanders. Ninety percent of the herbicide used in the Chilliwack Valley is glyphosate (Vision®); Triclopyr (Release®) and 2-4-D are also used on a limited basis to control the growth of maple and alder (Stad pers. comm. 2000). In most years, these chemical treatments account for less than 1% of the total site-preparation activity in BC, and far less is used in southern versus northern parts of the province (Govindarajulu 2008). Little is known about the effects of herbicides on stream-dwelling salamanders. Studies conducted on anurans have found malformations and mortalities associated with exposure to herbicides (e.g., Dial and Bauer 1984; Ouellet et al. 1997). The LC10 value (estimated dose at which 10% mortality occurs) for amphibians tested using Vision® has been found to be at or below the expected environmental concentration for that herbicide (Govindarajulu 2008). In 2004, Howe et al. (2004) concluded that the toxicity of glyphosate-based pesticides was due to the surfactant present in the preparations rather than to the active herbicidal ingredients. Formulations that do not contain the harmful surfactant have been found to be less toxic to amphibians (Govindarajulu 2008).

IUCN-CMP Threat # 11 Climate change & severe weather

11.1 Habitat shifting & alteration (Low impact), 11.2 Droughts (Low impact), 11.3 Temperature extremes (Low impact), 11.4 Storms & flooding (Low impact)

A description of this threat is inserted from COSEWIC (2014):

Potential future effects of climate change on Coastal Giant Salamanders are difficult to estimate, but negative effects could occur through stream drying and reduced availability of moisture on the forest floor, leading to shorter seasonal activity periods as a result of more frequent or prolonged droughts in spring – summer. Wetter and warmer winters could possibly counteract these effects to some degree. Higher frequency and intensity of flooding events could lead to flash floods and debris flows, and increased siltation of streams, resulting in direct mortality and reduced habitat quality for larvae. Stream amphibian surveys conducted in an unharvested landscape in Washington, found that D. copei had the strongest relationship to variables related to climate of the three species of giant salamanders studied, and the authors suggested that climatic factors (precipitation) could already be limiting that species’ range on the Olympic Peninsula (Adams and Bury 2002). Predicting the effects of climate change on stream amphibians is confounded by the fact that we have a poor understanding of their use of subsurface habitats that could serve as important refugia (e.g., subterranean chambers for nesting: Dethlefsen 1948; caves: BC CDC database; hyporheic zone of streams: Feral et al. 2005). As well, under a scenario where a permanent stream becomes intermittent due to climatic extremes, some Coastal Giant Salamanders within the population (e.g., large larvae) may be able to transform (Knopp pers. comm. 2012).

To estimate what the environmental conditions may be like under a climate change scenario, historical and projected data were summarized from the ClimateBC website for a random locality centered within the Coastal Giant Salamander range within BC (Latitude: 49° 04' 40”N, Longitude: -121° 52' 36”W, elevation 500 m; Spittlehouse 2006). Climate-normal data for this random BC locality for two time periods from 1961 – 2000 were compared to climate projections based on three different models for three time periods: 2020s, 2050s, and 2080s (Spittlehouse 2006). The average for the normal dataset was compared to the greatest change predicted from the three models for annual precipitation and temperature for the 2020 period (2010 – 2039).

For 2020, the models predict an increase in the amount of annual precipitation but a decrease in the amount of precipitation that will fall as snow. As well, the models predict an increase in amount of precipitation that will fall during the winter months, and a decrease in summer and fall. The mean annual temperature is expected to increase by 0.8°C, with the highest seasonal temperature increases expected in fall (by almost 2°C). These predicted climate changes are within the range that Coastal Giant Salamander experience at the southern end of the species’ range, where it is hotter and drier; for example, populations in Weaverville, California, experience on average 4°C higher temperatures and 632 mm less precipitation each year than populations in Chilliwack. Although the species may have a tolerance for greater climate extremes, it remains unclear whether local populations would need to, or could, adapt within the time frame projected by the models. As well, we know little of which occupied streams in the Chilliwack Valley have flows that are closely linked to the amount of snow pack and rate of snow melt. In summary, although much uncertainty exists, more droughts and flooding events associated with climate change are expected to shrink the availability of habitats, curtail dispersal, and further fragment populations. These responses are likely exacerbated by logging, road building, and other human activities that continue to modify habitats through cumulative effects.

This section replaces the “Recovery Goal”, “Rationale for Recovery Goal” and “Recovery Objectives (2009 – 2013)” sections in the provincial recovery strategy.

Environment and Climate Change Canada has determined the Population and Distribution Objective for the Coastal Giant Salamander to be:

To maintain the distribution, and to maintain or increase (where biologically and technically feasible) the abundance, of all extant populations of this species in Canada, including any new populations that may be identified in the future.

The Coastal Giant Salamander is naturally rare in Canada, having a small distribution that is restricted to the Chilliwack River drainage and adjacent streams, limited dispersal capabilities, slow reproductive rate, and specific habitat requirements. Currently there is insufficient information to complete a minimum population viability analysis. Likewise there is no information to indicate that the species was previously more widespread outside of its current range. The species was assessed as Threatened by COSEWIC owing to declines in the number of mature individuals, with future projected loss based on continuing declines in area, extent, and quality of suitable habitat. An objective to maintain stable or increasing populations of the Coastal Giant Salamander throughout the species’ range in B.C. is therefore deemed appropriate. Future improvements to the species’ condition may be possible by substantially reducing threats to individuals and by preserving the quality and availability of remaining suitable habitat.

A Recovery Planning Table is available in the adopted provincial recovery strategy (“Approaches Recommended to Meet Recovery Objectives” section). Environment and Climate Change Canada adopts this recovery planning table as the broad approaches for recovery of this species are still relevant and all current threats are addressed.

This section replaces the “Critical Habitat” section in the provincial recovery strategy.

Section 41 (1)(c) of SARA requires that recovery strategies include an identification of the species’ critical habitat, to the extent possible, as well as examples of activities that are likely to result in its destruction. The provincial recovery strategy for the Coastal Giant Salamander includes a description of the biophysical attributes of critical habitat. This science advice was used to inform the following critical habitat sections in this federal recovery strategy.

Critical habitat can only be partially identified at this time for the Coastal Giant Salamander owing to inadequate information about connective habitat needed by the species. The schedule of studies (Section 5.2) outlines the activities required to complete the identification of additional critical habitat necessary in supporting the population and distribution objectives for this species. Critical habitat for the Coastal Giant Salamander is identified in this document to the extent possible; as responsible jurisdictions and/or other interested parties conduct research to address knowledge gaps, the existing critical habitat methodology and identification may be modified and/or refined to reflect new knowledge.

Geospatial location of areas containing critical habitat

Critical habitat for the Coastal Giant Salamander is identified in the Chilliwack River drainage and adjacent streams in southwestern B.C. (Figures 2-8). Critical habitat for the Coastal Giant Salamander is based on all available verified occurrence records ^{Footnote 3} for the species.

Within the Chilliwack River drainage area where it occurs, the Coastal Giant Salamander requires both aquatic habitat (for reproduction as well as foraging, refuge and overwintering of larvae and neotenes ^Footnote4) and surrounding terrestrial habitat (for foraging, refuge, and overwintering) to complete life history functions. Together, the aquatic habitat and surrounding terrestrial habitat form the “core” critical habitat that is essential for the persistence of the local population. Core critical habitat is identified to encompass these movements and regular seasonal migration routes between aquatic and terrestrial habitat.

The area of terrestrial habitat adjacent to streams that is used by the Coastal Giant Salamander requires additional research in B.C.; however a radio-telemetry study in B.C. recorded a maximum distance of 66 m into upland habitat (Johnston 1998; Johnston and Frid 2002). Additionally, relevant research suggests that a distance of approximately 80 m is required to maintain the features of riparian habitat and riparian–stream linkages (Gomez and Anthony 1996; Brosofke et al. 1997; Young 2000). Based on the studies outlined, it is reasonable that an 80 m core critical habitat distance be required to maintain the full complement of ecological attributes immediately adjacent to inhabited and adjoining streams as areas essential to Coastal Giant Salamander. As many streams have been surveyed only once and have not been sampled along their entire length, the precautionary approach of applying the identification to all inhabited and adjoining headwater streams within the species' known range is considered appropriate considering the high likelihood of the Coastal Giant Salamander being present in suitable habitat within this range.

Longer movements of the Coastal Giant Salamander beyond core critical habitat may occur across additional upland habitat. These dispersal movements are not part of regular seasonal habitat use but allow for colonization of new breeding sites, and/or recolonization of those that are not available each year; as such they are required to maintain long-term persistence and gene flow among populations. The additional terrestrial habitat required to meet this species’ need is termed “connective” critical habitat. Coastal Giant Salamanders have been recorded further than 300 m from watercourses in B.C. (Welstead unpublished data 2016) and have been trapped at least 400 m from the stream edge (the furthest pit-fall trap distance in the study) in Oregon (McComb et al. 1993). NatureServe recommends a minimum extent of habitat use distance of 500 m, based on literature review in Hammerson (2004), and Environment and Climate Change Canada adopts this distance for “connective” critical habitat.

The areas containing critical habitat for the Coastal Giant Salamander are identified based on sequential application of the following methods (see also Figure 1):

1. Selection of watercourses associated with verified records: i.e., watercourses within 500 m of an occurrence, connecting streams between occurrences and all adjoining upstream headwater streams ^Footnote5;
2. Application of an 80 m distance on each side of selected watercourses to represent the “core” critical habitat comprising the essential aquatic and adjacent terrestrial areas required by the species for life history functions;
3. Application of a 500 m distance to all verified records and where these distances overlap with “core” critical habitat (and are not already identified as “core” critical habitat), to create “connective” critical habitat between the relevant watercourses;
4. Geospatial exclusion of any areas above 1200 m elevation ^Footnote6.

Biophysical features and attributes of “core” critical habitat

The Coastal Giant Salamander has a complex life history and the habitat needs of all life stages must be met for populations to persist. The salamanders typically inhabit small, cascading mountain streams and adjacent moist, shaded forest (up to 1200 m in elevation). Coastal Giant Salamanders require habitat for each of four distinct activities:

1. nesting and egg-laying,
2. aquatic larval development,
3. aquatic foraging, refuge, and overwintering of neotenes and
4. terrestrial foraging, refuge, and overwintering of juveniles and adults.

The habitat features and attributes required for each of the four distinct activities (as summarized in Table 3) overlap biophysically, geospatially, seasonally, and across life history stages.

^g Hyporheic zone: area where surface and shallow groundwater mix beneath and lateral to streambeds.

^h Johnston 2004

ⁱ Dupuis et al. 1995; Ferguson 1998

Biophysical features and attributes of “connective” critical habitat

The biophysical features and attributes required for Coastal Giant Salamander life history functions in connective habitat areas are summarized in Table 4.

The areas containing core and connective critical habitat for the Coastal Giant Salamander are presented in Figures 2-8. Core critical habitat for the Coastal Giant Salamander occurs within the shaded yellow polygons shown on each map where the core habitat biophysical features and attributes described in this section occur. Connective critical habitat for the Coastal Giant Salamander occurs within the shaded pink polygons shown on each map where the connective habitat biophysical features and attributes described in this section occur. Within these polygons, only clearly unsuitable areas that do not support the species in any life history stage (i.e., do not contain any of the biophysical features and attributes required by the species at any time) are not identified as critical habitat. Examples of clearly unsuitable habitats include existing permanent infrastructure (running surface of paved roads and/or artificial surfaces, buildings), and elevations over 1200 m. The 1 km x 1 km UTM grid overlay shown on these figures is a standardized national grid system that highlights the general geographic area containing critical habitat, for land use planning and/or environmental assessment purposes.

The following schedule of studies (Table 5) outlines the activity required to complete the identification of critical habitat for the Coastal Giant Salamander ^Footnote7.

Understanding what constitutes destruction of critical habitat is necessary for the protection and management of critical habitat. Destruction is determined on a case by case basis. Destruction would result if part of the critical habitat were degraded, either permanently or temporarily, such that it would not serve its function when needed by the species. Destruction may result from a single or multiple activities at one point in time or from the cumulative effects of one or more activities over time. Activities described in

Table 6 include those likely to cause destruction of critical habitat for the species; destructive activities are not limited to those listed.

^j Threat classification is based on the IUCN-CMP (World Conservation Union–Conservation Measures Partnership) unified threats classification system.

^k See Canadian Water Quality Guidelines for the Protection of Aquatic Life and Working Water Quality Guidelines for British Columbia

This section replaces the “Performance Measures” section in the provincial recovery strategy.

The performance indicators presented below provide a way to define and measure progress toward achieving the population and distribution objective:

• The distribution of the Coastal Giant Salamander in Canada has been maintained (i.e., extent of occurrence and area of occupancy has not decreased); and,
• The abundance of the Coastal Giant Salamander in Canada has been maintained or is naturally increasing (i.e., population sizes have not decreased).

This section replaces the “Statement on Action Plans” section in the provincial recovery strategy.

One or more action plans for the Coastal Giant Salamander will be posted on the Species at Risk Public Registry by 2022.

This section replaces the “Effects on Other Species” section in the provincial recovery strategy.

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

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

The Coastal Giant Salamander occurs in and around the Chilliwack River valley where other rare species are found, several of which use similar habitats. The recommended habitat protection will indirectly benefit other species in the area that depend on small streams, riparian areas and nearby forests. For example, the SARA Schedule 1 wildlife species that may benefit from protective measures taken for Coastal Giant Salamander include: Northern Spotted Owl (Strix occidentalis caurina; Endangered); Coastal Tailed Frog (Ascaphus truei; Special Concern); Tall Bugbane ( Actaea elata ; Endangered); and Mountain Beaver (Aplodontia rufa; Special Concern). Other SARA listed species may also benefit from recovery efforts, though their distribution is limited to lower elevation zones: Pacific Water Shrew (Sorex bendirii; Endangered); and Oregon Forestsnail (Allogona townsendiana; Endangered).

Negative effects on prey species, such as Coastal Tailed Frog tadpoles and aquatic invertebrates, are possible in localized areas. However, Coastal Giant Salamanders have a long evolutionary history of coexistence with these organisms, and any negative effects are expected to be offset by increased benefits from habitat management and protection. Recovery planning activities for the Coastal Giant Salamander will be implemented with consideration for all co-occurring species, with focus on species at risk, such that inadvertent negative impacts to individuals and their habitats are avoided.

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Ferguson, H.M. 1998. Demography, dispersal and colonisation of larvae of Pacific Giant Salamanders (Dicamptodon tenebrosus, Good) at the northern extent of their range. M.Sc. thesis, University of British Columbia, Vancouver, BC. 131 pp.

Gomez, D.M., and R.G. Anthony. 1996. Amphibian and reptile abundance in riparian and upslope areas of five forest types in western Oregon. Northwest Sci. 70, 109–119.

Govindarajulu P., C.Nelson, J. LeBlanc, W. Hintz, and H. Schwantje. 2013. Batrachochytrium dendrobatidis surveillance in British Columbia 2008 - 2009, Canada. British Columbia Ministry of the Environment. Report ID 34795.

Govindarajulu, P.P. 2008. Literature review of impacts of glyphosate herbicide on amphibians: What risks can the silvicultural use of this herbicide pose for amphibians in B.C.? B.C. Wildlife Report No. R-28. Ministry of Environment, Victoria, British Columbia.

Hall, J.D., M.L. Murphy, and R.S. Aho. 1978. Community Ecology and Salamander Guilds. Cambridge University Press, Great Britain. 230 pp.

Hammerson, G. 2005. Population/occurrence delineation. Spadefoots. In NatureServe (2016). NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. [Accessed July 2016]

Hawkins, C.P., M.L. Murphy, N.H. Anderson, and M.A. Wilzbach. 1983. Density of fish and salamanders in relation to riparian canopy and physical habitat in streams of the northwestern United States. Canadian Journal of Fisheries and Aquatic Science 40:1173–1185.

Hossack, B.R., M.J. Adams, E.H. Campbell Grant, C.A. Pearl, J.B. Bettaso, W.J. Barichivich, W.H. Lowe, K. True, J.L. Ware, and P.S. Corn. 2010. Low prevalence of chytrid fungus (Batrachochytrium dendrobatidis) in amphibians of U.S. headwater streams. Journal of Herpetology 44(2):253–260.

Howe, C.M., M. Berrill, B.D. Pauli, C.C. Helbing, K. Werry, and N. Veldhoen. 2004. Toxicity of glyphosate-based pesticides to four North American frog species. Environmental Toxicology and Chemistry 23(8):1928–1938.

Johnston, B. 1998. Terrestrial Pacific Giant Salamanders (Dicamptodon tenebrosus Good): natural history and their response to forest practices. M.Sc. thesis. Univ. of British Columbia, Vancouver, BC. 98 pp.

Johnston, B.E. 2004. Accounts and Measures for Managing Identified Wildlife. V. 2004. Coastal Giant Salamander (Dicamptodon tenebrosus)(PDF; 154 Ko). Prepared for the Ministry of Water, Land and Air Protection, Surrey, BC.

Johnston, B., and L. Frid. 2002. Clearcut logging restricts the movements of terrestrial Pacific giant salamanders (Dicamptodon tenebrosus Good). Can. J. Zool. 80, 2170–2177.

Knapp, R. A., C. J. Briggs, T. C. Smith, and J. R. Maurer. 2011. Nowhere to hide: impact of a temperature-sensitive amphibian pathogen along an elevation gradient in the temperate zone. Ecosphere 2(8):1-26

Knopp, D., pers. comm. 2012. Communication to E. Wind. BC's Wild Heritage Environmental. Chilliwack, BC. Cited in COSEWIC (2014).

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Prepared by the Pacific Giant Salamander Recovery Team

British Columbia Ministry of Environment

April 2010

Photograph by Laura Friis

Additional copies can be downloaded from the B.C. Ministry of Environment Recovery Planning webpage

Content (excluding illustrations) may be used without permission, with appropriate credit to the source.

This recovery strategy has been prepared by the Pacific Giant Salamander (Dicamptodon tenebrosus) Recovery Team, as advice to the responsible jurisdictions and organizations that may be involved in recovering the species. The British Columbia Ministry of Environment has received this advice as part of fulfilling its commitments under the Accord for the Protection of Species at Risk in Canada, and the Canada - British Columbia Agreement on Species at Risk.

This document identifies the recovery strategies that are deemed necessary, based on the best available scientific and traditional information, to recover Pacific Giant Salamander (Dicamptodon tenebrosus) populations in British Columbia. Recovery actions, which have been derived to achieve the goals and objectives identified herein, are subject to the priorities and budgetary constraints of participatory agencies and organizations. These goals, objectives, and recovery approaches may be modified in the future to accommodate new objectives and findings.

The responsible jurisdictions and all members of the recovery team have had an opportunity to review this document. However, this document does not necessarily represent the official positions of the agencies or the personal views of all individuals on the recovery team.

Success in the recovery of this species depends on the commitment and cooperation of many different constituencies that may be involved in implementing the directions set out in this strategy. The Ministry of Environment encourages all British Columbians to participate in the recovery of the Pacific Giant Salamander (Dicamptodon tenebrosus).

Pacific Giant Salamander Recovery Team

The recovery strategy for Pacific Giant Salamander (Dicamptodon tenebrosus) was developed by the Pacific Giant Salamander Recovery Team as advice to the Province of British Columbia.

Pacific Giant Salamander populations occur in the Chilliwack Forest District of British Columbia. The British Columbia Ministry of Environment is responsible for producing a recovery strategy for this species under the Accord for the Protection of Species at Risk in Canada.

The original (2004) version of this report was prepared by Kristina Ovaska, Lennart Sopuck, Ross Vennesland, and Christian Engelstoft with input from Dennis Knopp and members of the Pacific Giant Salamander Recovery Team. The B.C. Ministry of the Environment has since developed a new set of recovery strategy format guidelines, and the Recovery Team is therefore submitting an updated version of the recovery strategy. Revisions and updates were made by Kym Welstead with assistance from Lennart Sopuck and Kristiina Ovaska. Jeff Brown, David Toews, Stephen Hureau, Marie-José Ribeyron, and Todd Manning provided useful comments on an earlier version of the revised strategy.

Many people have generously contributed information for this report. Sylvia Letay, Barbara Johnston, Marta Donavan, Erin Prescott, John Richardson, Jim Vickerson, Christine Chapman, Marie Goulden, Arthur Robinson, Gene MacInnes, and Todd Ewing contributed data and/or information on land use within the range of the Pacific Giant Salamander. Laura Friis, Mark Stone, Laura Matthias, and Kevin Chernoff helped with spatial data, literature search, and review and compilation of the report. Kelly McAllister and Bill Leonard kindly provided information on the distribution of the species in Washington State. Hartwell Welsh generously allowed us to use his unpublished map of the global distribution of this species prepared for A Field Guide to the Amphibians of Northwestern North America (Jones and Leonard [eds.] 2005).

The Pacific Giant Salamander is a large charismatic salamander that can grow up to 30 cm in length. This marbled golden brown salamander is the only member of the family Dicamptodontidae that occurs in Canada. The species' range extends from extreme southwestern British Columbia through western Washington and Oregon to northwestern California. In Canada, the species is largely restricted to the Chilliwack River drainage in British Columbia. It is currently known from about 75 streams and tributaries within 15 stream systems. Because of the species' restricted Canadian distribution and threats to its habitat from forestry, urban developments, road building, and other human activities, the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) reassessed the national status of the Pacific Giant Salamander changing it from "Special Concern" to "Threatened" in 2000. The species is on the provincial Red list in British Columbia and is listed as Threatened under Schedule 1 of the federal Species at Risk Act (SARA). As well, the Conservation Framework has assigned Pacific Giant Salamanders a conservation priority 1, the highest priority rank under Goal 3: Maintain the diversity of native species and ecosystems (Ministry of Environment 2010a).

Characteristics of the species' life history and ecology that contribute to the vulnerability of populations and influence their recovery potential include limited dispersal ability both in aquatic and terrestrial habitats; complex life history; low reproductive potential; and close association with cool, clear headwater streams and creeks.

The Pacific Giant Salamander has a complex life history, which includes an aquatic and a terrestrial phase. The habitat needs of all life stages must be met for populations to persist. The salamanders typically inhabit small, cascading streams and adjacent moist, shaded forest. Aquatic larvae spend several years in the streams, where they shelter under rocks in small pocket pools of calmer water and feed on aquatic invertebrates. Adults live in moist, shaded forest, close to streams and require either abundant coarse woody debris, or other shelter on the forest floor. Under some circumstances larvae attain maturity without transforming and remain permanently aquatic; this process is termed neoteny.

The recovery goal is to ensure a well-connected, viable, and self-sustaining population of the Pacific (= Coastal) Giant Salamander (Dicamptodon tenebrosus) within secure habitat ^Footnote1 throughout its known range ^Footnote2 in Canada where habitat still exists or can be restored (achieve within 10 years). The short-term (5-year) objectives focus on securing known populations, preventing fragmentation, inventorying for unidentified populations, and restoring historical populations through management and protection of survival, recovery, and dispersal habitats in the aquatic and terrestrial environments.

The broad strategies or approaches for recovery consist of habitat protection, management and stewardship, habitat mapping, population inventories, habitat restoration, population and habitat monitoring, threat clarification, research, outreach, and stewardship. Although no critical habitat as defined under SARA is proposed for identification at this time, continued habitat protection is urgent for occupied sites as only 40% of the occupied sites are conserved in parks, protected areas, community watersheds, and Wildlife Habitat Areas. Currently 20 Wildlife Habitat Areas have been approved encompassing approximately 38 km (linear) of known occupied streamside habitat in the Chilliwack Forest District (Ministry of Environment 2010b; see Appendix 2). Increasing survey coverage is also urgent, as less than 20% of potential stream habitat has been surveyed to date. Habitat on private lands can be conserved through stewardship, including working with municipal and regional governments to achieve habitat objectives at landscape and broader levels. A draft action plan has been developed and will be updated after the posting of the recovery strategy.

ⁱ The common name of Pacific Giant Salamander reported in this recovery strategy follows the current naming convention of the Province of British Columbia.

The Pacific Giant Salamander is the largest salamander in British Columbia with length of adults about 15-30 cm, including the tail. The salamanders are robust with a large head, blunt snout, and stout legs. The colour pattern of adults is often reticulated or marbled with lighter tan or gold interspersed with dark brown or grey. Completely aquatic forms (neotenic form) are drab grey or brown and often lack the marbled pattern. Absence of parotoid or "poison" glands (a pair of prominent protuberances behind the head capable of exuding toxins) and larger size distinguish this species from the Northwestern Salamander (Ambystoma gracile), with which it might be confused. Aquatic larvae are dark brown or black without distinct markings. They have short, fuzzy external gills and a short tail fin and grow to about 9-17 cm in length. See field guides (e.g., Matsuda et al. 2006; Jones et al. [eds.] 2006) for photographs and detailed descriptions.

The distribution of the Pacific Giant Salamander extends from extreme southwestern British Columbia south through western Washington and Oregon to northwestern California (Figure 1). From east to west, the range extends from the eastern Cascade Mountain Range to the Pacific Coast. About 1% of the species' geographic range is in Canada.

The known Canadian range of the Pacific Giant Salamander is restricted to the Chilliwack River drainage and nearby smaller watersheds in southwestern British Columbia (COSEWIC 2000; MoE data files; Figure 2). Distribution records exist from the eastern slopes of Chilliwack Lake to the west side of Vedder Mountain, covering an area of about 850 km² (COSEWIC 2000). The salamanders are known from 15 stream systems or fourth-order watersheds (see Appendix 1 for a definition). Records exist from about 75 individual streams and tributaries based on data up to 2003 (estimated at 152 km [linear] of stream habitat; MoE, unpublished data files). ^Footnote3 The area of occurrence is uncertain because less than 20% of the streams with potential habitat have been surveyed. There are no confirmed records of the species north of the Fraser River. Historically, the salamanders probably occurred in additional stream systems within the Chilliwack Watershed and in the Sumas Prairie/Chilliwack area. Detection probability of larvae also differs with stream conditions and timing of surveys. ^Footnote4 Furthermore, many streams have been surveyed only once and have not been sampled along their entire length. Therefore, some of the streams deemed unoccupied may in reality support salamanders.

Dispersal of salamanders across the international border with the United States is possible but unlikely. In northwestern Washington State, the Pacific Giant Salamander occurs within the Nooksack and Skagit drainages (McAllister 1995; Washington Herp Atlas 2005). The closest locality records to the Chilliwack Valley population are from the North Fork drainage of the Nooksack River, about 10 km south of the Canadian border. Occupied streams that extend from Canada into Washington approach within 1-2 km of headwater streams of the Nooksack and Skagit drainages, but high elevation alpine passes between them probably pose a barrier to movements. The salamanders could possibly access one headwater tributary of Tamihi Creek from the Nooksack drainage, provided they were able to cross a narrow, forested saddle between the two drainages. Human settlements and agricultural activity within the Columbia Valley and along the Sumas River probably pose barriers to dispersal of salamanders into Canada along more western routes.

No distribution records exist from the upstream portions of the Chilliwack River or its tributary streams immediately south of the Canadian border, but this area is very isolated and the extent of surveys, if any, is unknown. A possible dispersal route into Canada may be along the upper Skagit Valley of Washington. The upper valley was flooded for hydro-electric development forming the Ross Lake Reservoir, which extends into Canada. The closest known locality record along the Skagit Valley in Washington is from about 45 km south of the Canadian border. Presently, the Ross Dam on the Skagit may limit dispersal potential of these populations, which lie downstream of the dam. However, it is possible that salamanders dispersed into Canada along the Skagit Valley in the past. Additional surveys for salamanders may be worthwhile within the Skagit and Silverhope drainages, especially adjacent to the U.S. border.

No information is available on population trends. A rough estimate of the population size in the Chilliwack drainage was given in COSEWIC (2000): about 13,400 terrestrial adults and 4500-9000 aquatic, neotenic adults, but a large error may be associated with this estimate. ^Footnote5 The overall distribution boundaries of the species in Canada are believed to have changed little in recent history, although presently unoccupied streams with suitable habitat may have been occupied in the past (Haycock 1991; COSEWIC 2000). An exception is a possible loss of a local population from the Sumas Prairie area due to extensive habitat modification in the early 1900s, when Sumas Lake was drained.

Within the past century, human activities and wildfires have extensively altered forest habitats over much of the species' Canadian range. Forest cover maps indicate that as of the year 2000, about 75% of the forest within Giant Salamander range (< 1200 m above sea level [asl]) was less than 120 years old. Most remaining old-growth forests are found at high elevations (> 1000 m asl) and, as a result, may be of less value to salamanders because of the harsh conditions at these elevations. Forestry and urban developments continue to modify habitats in the area today.

The Pacific Giant Salamander is ranked as nationally imperiled in Canada, but is considered to be secure globally and in the United States (see Table 1 for subnational ranks). It is on Schedule 1 under the Canada Species at Risk Act. It is also a Priority 1 species under Goal 3: maintain the diversity of native species and ecosystems of the B.C. Conservation Framework for details, Ministry of Environment 2010a).

Habitat and biological needs

The Pacific Giant Salamander has a complex life history, which includes an aquatic and a terrestrial phase. Under some circumstances, aquatic larvae attain sexual maturity and do not metamorphose (facultative neoteny). The habitat needs of all life stages must be met for populations to persist.

General habitat associates

In Canada, the Pacific Giant Salamander occurs within the Coastal Western Hemlock biogeoclimatic zone. Although the species has occasionally been found in larger water bodies (Chilliwack Lake and Chilliwack River), most sightings have been near headwater streams and the adjacent terrestrial habitats (COSEWIC 2000). Suitable streams are small, typically cascading with pools, and may run through a variety of moist forest types and plant communities (Farr 1989; Haycock 1991). Most of these streams are classified as permanent, although locality records from the west slope of Vedder Mountain are from streams too small to appear on maps. Some of these streams may be partially subterranean or seasonally intermittent.

In British Columbia, the species is typically associated with moist forest stands and has been recorded from stands with Douglas-fir (Pseudotsuga menziesii), western hemlock (Tsuga heterophylla), and western redcedar (Thuja plicata) (Haycock 1991). These salamanders appear to prefer moist habitats, as indicated by the frequent presence of devil's club (Oplopanax horridus) and salmonberry (Rubus spectabilis) in the shrub layer of their habitats. In Washington, the species has been found in western hemlock, western redcedar, and grand fir (Abies grandis) dominated forests and is absent from drier forests, such as ponderosa pine (Pinus ponderosa) (Haycock 1991). However, in Oregon the Pacific Giant Salamander has been known to occur in drier forest types where it has been associated with springs and seepages (Farr 1989).

In British Columbia, these salamanders appear to be restricted to elevations below 1200 m. The B.C. Conservation Data Centre database contains one record from an elevation of 1700 m, but the accuracy of that record cannot be confirmed. In the Chilliwack Valley, the average elevation of 22 occupied sites in headwater streams was 600 m (range: 140-1150 m). ^Footnote6

At the landscape level (such as a tributary watershed), the species appears to have rather general habitat requirements, and studies both in the United States (Corn and Bury 1991; Welsh and Lind 2002) and British Columbia ^Footnote7 have found few correlations with habitat attributes, apart from decreased larval abundance with elevation. A study in California and Oregon (Welsh and Lind 2002) found no significant habitat correlations at the landscape level. At the macro-environmental (reach) level, habitat attributes had slightly more predictive power: salamander abundance varied negatively with an understory consisting of deciduous trees and grass, suggesting possible avoidance of ground disturbance and natural openings that often support these vegetation types. At the micro-environmental level (i.e., water and substrate features within a small portion of a reach), the habitat requirements of the salamanders were more specific, suggesting an overriding influence of microhabitat and microclimatic features on their distribution. In California, salamander abundance was correlated with increased pool density and pebble and bedrock substrates (Welsh and Lind 2002). These results are in accordance with those of previous studies (reviewed in COSEWIC 2000), and underline the importance of narrow, shaded streams with coarse, rocky substrates and abundant pocket pools and riffles. Notably, however, that the above studies mostly deal with requirements of the aquatic, rather than the terrestrial phases of the species.

Terrestrial adults occupy forested riparian habitats close to streams and require abundant shelter (Johnston 1998; Johnston and Frid 2002). Neotenic adults require permanent, relatively deep water and often occur at high elevations or, at lower elevations, and in large permanent water bodies (such as Chilliwack Lake and Chilliwack River).

Habitat requirements at different life stages

The following habitat features have been identified as important for the different life history phases of the Pacific Giant Salamander in the Chilliwack area (Farr 1989; Haycock 1991; COSEWIC 2000).

Reproductive stage

In British Columbia, development from egg to metamorphosis may take 4-6 years, compared to 2-3 years in Oregon (reviewed in COSEWIC 2000). The salamanders are long lived (20 years or more), and their reproductive potential is low. Pacific Giant Salamanders will create a "nest" where courtship, mating, and egg-laying occur in water-filled chambers under rocks, logs, or other cover-objects either within the stream or along its immediate shoreline (COSEWIC 2000; MoE 2004). Eggs have been found from the spring to autumn (Matsuda et al. 2006). The clutch size ranges from 85 to 200 eggs, which are colourless, very large (about 6.5 mm in diameter), and individually attached to the roof of the nest chamber by a short, gelatinous stalk (COSEWIC 2000). Females are thought to guard the developing eggs and young and may remain with them at the nest site for up to 200 days (Nussbaum et al. 1983).

Aquatic larvae

The following habitat features are deemed important:

• small, cool, clear, well-oxygenated, moderate- to fast-flowing streams;
• permanent streams with a stable channel (not subject to scouring in spring or to drying up in summer);
• presence of small "pocket" pools in streams; and
• gravel and pebble substrate with refuges large enough to cover the animal.

Larval abundance tended to increase with decreasing wetted width. ^Footnote8The average wetted width where salamanders were found was 2.25 m (range: 0.7-10 m). Further habitat features examined at different spatial scales (stream, reach, and microhabitat) showed few correlations with larval abundance, with most correlations being at the microhabitat level. ^Footnote9 The above study found a positive correlation of larval abundance with pocket pool density, decreased water velocity, and increased rock coverage. Pools with sand and large (> 2 m diameter) angular rocks provided habitat complexity and seemed to be preferred (Haycock 1991). Farr (1989) also stressed the importance of refuges for larval and other phases of this species in British Columbia. Several studies in the United States have shown similar correlations, and one study demonstrated experimentally that larval abundance increased with the availability of refuges, consisting of rocks of various sizes (Parker 1991).

Terrestrial phase

The following habitat features are deemed important:

• moist shady forest habitat adjacent to streams, such as in old-growth and mature second-growth forests;
• availability of refuges, such as decaying logs or other cover; and
• NESTING sites in or immediately adjacent to stream.

Few studies have addressed the habitat requirements of terrestrial phases of the salamanders. In old growth Douglas-fir dominated stands in Washington and Oregon, Corn and Bury (1991) found that terrestrial giant salamanders were most common in moderately moist and wet areas. In the Chilliwack Valley and adjacent areas in northwestern Washington, Johnston (1998) found that terrestrial adults typically occupied riparian areas.

In British Columbia, Johnston (1998) also found the species using both clearcuts (< 10 years old) and older forests, but in the clearcuts individuals altered their behaviour in ways consistent with moisture stress. Although terrestrial phases may not require old growth, they require old-growth attributes, such as large, well-decayed downed logs and other coarse woody debris, and moist forest floor conditions.

Both Farr (1989) and COSEWIC (2000) suggested that nesting sites (i.e., residences) form an essential habitat attribute for this species. Females are thought to guard the developing eggs and young and may remain with them at the nest site for up to 200 days (Nussbaum et al. 1983). Very few nests have ever been found anywhere within the range of the species. In British Columbia, Farr (1989) reported very small larvae from small spring-fed creeks on Vedder Mountain, and suggested that small stable creeks with abundant cover provide important nesting habitat.

Terrestrial adults appear to use similar refuges during winter as during other seasons, and the availability of overwintering habitat is not considered to be a limiting factor (COSEWIC 2000). However, little information is available on overwintering habitats.

Neotenic phase

In the Chilliwack area, neotenic adults are found at higher elevations (600-1100 m) and in large permanent water bodies at low elevations (Chilliwack Lake and River) (Haycock 1991). Neoteny is probably facultative in this species, although the two phases (terrestrial and aquatic adults) seem to be spatially segregated to some degree. Like aquatic larvae, neotenic adults require abundant shelter provided by rocks, boulders, or other coarse bottom substrates. They also require permanent, relatively deep water. Nothing specific is known about nesting habitats of neotenes.

Movement and dispersal

Movement within the riparian area was studied in the Chilliwack Valley and adjacent areas in northwestern Washington. Johnston (1998) and Johnston and Frid (2002) found that the majority (average of 67%) of locations of 18 radio-tracked adults in old-growth and mature second-growth forest were within 5 m of the stream bank. Of all locations, 80% were within 20 m and 88% were within 40 m of the stream bank (Johnston 1998; Johnston and Frid 2002). The longest distance of an adult from the stream bank was 66 m. Therefore, a minimum habitat width of 50 m each side of the watercourse would encompass most regular movements of adults along the riparian habitat. The extent of terrestrial habitat that the salamanders require is likely to vary both with the configuration and quality of habitat. Furthermore, terrestrial movements of different sex and age classes are unknown for this species.

Although terrestrial adults typically restrict their movements to small areas, they are capable of moving longer distances if environmental conditions are suitable (e.g., during periods of increased rainfall or when the ground is moist and temperatures are mild) (Johnston 1998, 1999). Availability of dispersal habitat is needed to enable these longer movements to allow dispersal of salamanders between streams and drainages. Dispersal of individuals among streams is important for maintaining genetic heterogeneity and population viability (COSEWIC 2000). Several studies in Oregon have reported the Pacific Giant Salamander up to 400 m from stream edges (reviewed in Olson et al. 2007). Sub-adult movements have not been studied and this stage may be responsible for most of the dispersal, as is the case in many other species (Horn 1983; Duellman and Trueb 1986, cited in MoE 2004; Trenham and Shaffer 2005).

The salamanders appear to occasionally use subterranean watercourses as travel corridors (D. Knopp, pers. comm. 2003). Subterranean streams could aid in dispersal, but only circumstantial evidence is available. Terrestrial adults are primarily active at night. During dry periods, their movements were restricted to times of low temperatures (Johnston 1998).

Larval salamanders are very sedentary and tend to remain in the same stretches of the stream even from year to year (Ferguson 2000), ^Footnote10 where they shelter under rocks and other cover. Transplant experiments have established that larval salamanders can successfully inhabit an unoccupied nearby streams. ^Footnote11 Larval mark-recapture studies found 73% of larvae stayed within 10 m of their initial location of capture over 3 years, and that only 10% of larvae ventured farther than 20 m over 2 years (Ferguson 1998). This finding supports the notion that the majority of dispersal occurs overland in adult and sub-adults and reinforces the importance of suitable terrestrial dispersal habitat to ensure gene flow.

Important terrestrial dispersal habitat probably has all of the following characteristics:

• elevation < 1200 m;
• a network of stream riparian zones;
• good canopy cover, such as in moist, old-growth or mature second-growth forest; and
• abundant cover on the forest floor, such as coarse woody debris including large pieces in advanced stages of decay.

Ecological role

The Pacific Giant Salamander plays an important role in the ecosystem as a top predator through predator-prey interactions. The species reaches the northern limits of its distribution in southern British Columbia. Populations at the periphery of a species' distribution might possess unique adaptations and contribute significantly to genetic diversity (Scudder 1989), and the general patterns of range collapse of many vertebrates have been towards the periphery of their ranges (Lomolino and Channell 1995, 1998). Peripheral populations may enhance a species' ability to respond to broad-scale environmental perturbations, including climate change. The British Columbia population may become increasingly important for the survival of the species in the future, if global climate change alters the cool, stream habitats occupied by the salamanders farther south.

Limiting factors

Limited dispersal ability

Larvae are relatively sedentary and typically confine their movements to small sections of streams (Ferguson 1998, 2000). ^Footnote10 The colonizing ability of larvae is poor (Ferguson 2000). Terrestrial adults are also relatively sedentary and appear to seldom move between streams (Johnston 1998; Johnston and Frid 2002). However, they are capable of moving longer distances overland and possibly colonizing vacant habitat under favourable, moist conditions. Limited dispersal ability poses constraints to recovery in disturbed habitats and makes the population more susceptible to habitat fragmentation, which can isolate subpopulations.

Complex life history and restricted habitat requirements

A suitable juxtaposition of aquatic and terrestrial habitats is required for the salamanders to complete their life cycle. Although a complex life history and options such as whether to metamorphose into a terrestrial form or to remain in the aquatic habitat increase the resiliency of the species, impacts of human activities on different life history stages can be cumulative and interact in complex ways. The species is dependent on a specific set of habitat features both in streams and in adjacent forest habitats. The species is closely associated with cool, clear headwater streams and creeks, and availability of dispersal habitat remains a key issue.

Low reproductive potential

The Pacific Giant Salamander matures slowly, and females reproduce infrequently and are thought to breed only once every 2 years (Nussbaum 1976). In the Chilliwack Valley, development from egg to metamorphosis may take as long as 4-6 years, compared to 2-3 years in the centre of the species' range in Oregon (COSEWIC 2000). Low reproductive potential, together with limited dispersal ability, may contribute to low recovery rates after a disturbance.

Vulnerability of peripheral populations

The species exists at the northern extremity of its distribution in southern British Columbia. The persistence of peripheral populations is inherently precarious due to harsher climate, lower survival rates and abundance, and stochastic fluctuations in population size (Lawton 1993).

Threat classification

Table 2. Threat classification table for the Pacific Giant Salamander.

Table 2.1 Forestry activities affecting aquatic habitat

Table 2.2 Forestry activities affecting terrestrial habitat

Table 2.3 Urban and rural development

Table 2.4 Micro-hydro developments

Table 2.5 Pollution

Table 2.6 Climate change

Table 2.7 Disease

Table 2.8 Introduced fish

Table 2.9 Recreational activities

Description of the threats

Forestry activities

Historical and recent forestry practices have modified forest habitats within much of the Canadian range of the Pacific Giant Salamander. Forestry activities continue to be widespread, and little older forest remains, particularly at lower elevations. Forestry activities include logging, associated road building, construction of landings and helipads, and various silvicultural activities/prescriptions that have the potential to remove ground vegetation or disturb the forest floor (i.e., soil layer, coarse woody debris, herbaceous/shrub cover) and change the forest composition and strata. In aquatic habitat, canopy removal increases water temperatures, and logging and road building have the potential to cause siltation, which fills in cracks and crevices and reduces shelter required by giant salamander larvae (Bury and Corn 1988). Logging practices may also reduce the persistence of small streams, particularly in dry years, resulting in loss of habitat, isolation of subpopulations, and possibly direct mortality (Cannings et al. 1999; COSEWIC 2000). In terrestrial habitat, canopy removal results in changes to the microclimate at ground level, including temperature and moisture regimes. Logging also alters the structure of the forest floor (i.e., changes in ground cover and amount and distribution of coarse woody debris) potentially limiting the availability and type of shelters for terrestrial salamanders. Clearcut logging constrains movements and dispersal of terrestrial phases of this salamander (Johnston 1999; Johnston and Frid 2002). These constraints can potentially isolate populations leading to lower survivorship and reduction in genetic variability

With the adoption of the Forest Practices Code of British Columbia Act in 1995 and the Forest and Range Practices Act (FRPA) in 2003, common standards have been applied to forestry practices throughout the province. Regulations pertaining to the construction of roads, in particular, have benefited habitats of the Pacific Giant Salamander by reducing siltation of streams due to erosion. However, stream buffering of small, fishless headwater streams is not required under FRPA unless constrained by some other mechanism such as a Wildlife Habitat Area. Watershed restoration plans within some areas of the Chilliwack Valley have addressed and attempted to restore habitats degraded by earlier logging practices.

Studies in the Chilliwack drainage system since 1994 have revealed that the effects of logging on the Pacific Giant Salamander are complex and often subtle (Richardson and Neill 1998; Johnston 1999; Johnston and Frid 2002). ^Footnote8 For example, larval densities and body size differed between stream stretches adjacent to clearcuts and old-growth stands, possibly as a result of changes in growth rates, immigration rates, and/or survival (Richardson and Neill 1998). ^Footnote12 In terrestrial habitat, adults in clearcuts altered their movement patterns consistent with moisture and temperature stress when compared to their behaviour in the adjacent forest (Johnston 1999; Johnston and Frid 2002). Effects of such changes on population sizes and dynamics are unknown and not easily studied.

Urban and rural development

Urban, industrial, and agricultural developments in the Chilliwack and adjacent watersheds continue to diminish aquatic and terrestrial habitats. Removal of forest cover and/or changes in drainage patterns in and around developments can lead to loss, fragmentation, and severe degradation of habitats. Currently, the effects of new developments are local and restricted to areas zoned for residential, commercial, or agricultural developments, which comprise about 9% of the species' range. However, developments occur in productive, lower elevation areas, leading to the loss and degradation of high-quality habitat for the salamanders.

Micro-hydro developments

Micro-hydro developments along a stream usually consist of a water intake structure (small dams, intake structures, or "run-of-river" systems), penstock/water conduit structures, small power plant with turbines, access road, and a power transmission line corridor. Such developments could lower or alter water flows, increase water temperature, result in removal of riparian vegetation, and create above-ground obstacles to movements of salamanders. As of 2009 there are 17 documented micro-hydro power water licence applications within the known range of the Pacific Giant Salamander (British Columbia Ministry of Environment 2009), although some of these may no longer be active.

Pollution

The main sources of pollution are contaminants in the run-off from residential and industrial developments and pesticide application on forestry lands. Accidental spills of hazardous materials such as fuels or lubricants can also contaminate streams. According to permit regulations for the Chilliwack Valley, herbicides cannot be applied within 10 m of large streams, and small headwater streams can only be sprayed when they are dry, thus reducing potential impacts on salamanders and other species using aquatic habitats. Herbicides such as the glyphosate formulation Roundup have been shown to reduce survival of amphibian larvae if the herbicide enters the water column (Relyea 2005). Synergistic interactions between pesticides and stress magnify the effects in some species of amphibians (Relyea 2005).

Climate change

Global climate change is predicted to result in increased incidence of summer droughts and extreme weather events such as flooding in winter (Gates 1993; IPCC 2001; MoE 2007). Increased aridity can affect persistence of streams and the availability of moist refuges in terrestrial habitats. Increased flooding due to severe storms can alter the habitat structure of streams. Impacts of climate change may be exacerbated in landscapes fragmented by logging and other human activities. For example, effects of prolonged summer droughts may be especially severe in logged landscapes, further reducing suitable moist refuges available for salamanders on the forest floor. Small streams may similarly be prone to increased drying in areas with reduced canopy cover, reducing quality and quantity of aquatic habitat.

Disease

Increased access through forestry roads and recreational trails may result in the spread of infectious diseases by humans to the salamander population. For example, sport fishers could spread disease organisms among different streams in their gear. Of particular concern is a pathogenic chytrid fungus (Batrachochytrium dendrobatidis), which has been implicated in amphibian declines in the western United States and globally (Daszak et al. 1999). Other pathogens that are associated with epidemic disease in amphibians are the water mold Saprolegnia ferax, which can be transmitted from fish to amphibians, and various iridoviruses (Daszak et al. 1999). Mortality associated with chytrid fungal infection has been reported from the Idaho Giant Salamander, Dicamptodon aterrimus (USGS 2001). At present there is no evidence that outbreaks of disease are a problem for Pacific Giant Salamander populations, but in light of the role of chytridiomycosis in precipitous declines of amphibian populations worldwide, the threat must be taken seriously.

Introduced fish

Pacific Giant Salamanders, especially young of the year, are vulnerable to predation by salmonid fish (Rundio and Olson 2003). The use of small headwater streams by Pacific Giant Salamanders for breeding and nurseries is considered to be at least partially an adaptation to avoid predation (COSEWIC 2000). The presence of fish may also increase competition for food resources in streams. Stocking of sport fish within the Chilliwack River Watershed may pose an important threat to this species (Orchard 1984). The extent of fish introductions and spread to headwater streams and water bodies within the Chilliwack drainage is unknown.

Recreational activities

Riparian and stream habitats can be adversely affected by the use of all terrain vehicles, mountain bikes, or other intensive recreational activities that result in erosion, siltation, and damage to riparian vegetation. Such intensive activities are localized and impacts on salamanders are minor at present. Spread of disease is potentially a greater threat (see section Disease, above).

• Research: larval ecology and forestry interactions (Ferguson 1998, 2000; Richardson and Neill 1998). ^Footnote13, ^Footnote14
• Research: movements of terrestrial adults and forestry interactions (Johnston 1998, 1999; Johnston and Frid 2002).
• Inventories:
  • University of British Columbia (1994-2000)
  • Department of National Defence lands (Knopp and Larkin 1995)
  • B.C. Conservation Corps (2006, private lands west side of Vedder Mountain and eastern hillsides)
• Habitat modeling: analyses done for an earlier of version of this document in 2004. ^Footnote15
• 20 Wildlife Habitat Areas were approved in 2007 encompassing approximately 38 km (linear) of known occupied streamside habitat in the Chilliwack Forest District (Ministry of Environment 2010b; see Appendix 2 for details).

• Distribution within known range, including unsurveyed streams, those visited only once, and persistence in streams with only historical records; possible presence within other, adjacent drainages containing suitable habitat.
• Population dynamics, especially at landscape level.
• Reproduction and life history, including larval growth rates, period of larval phase, and age-specific survival rates in both aquatic and terrestrial habitats.
• Characteristics and availability of nesting sites.
• Characteristics of dispersal habitat and salamander movements.
• Effectiveness of linear riparian buffers prescribed for Wildlife Habitat Areas in protecting salamander populations.
• Further clarification of threats from all sources.

The Recovery Team believes that the recovery can be completed within a relatively short time-frame through habitat protection and restoration. The species can tolerate some degree of human disturbance, although it is unknown how much further habitat alteration the population can withstand. If reintroduction is deemed necessary in the future, translocation of individuals to currently unoccupied streams that contain suitable habitat is feasible. ^Footnote16

The overall long-term goal (achieve within 10 years) for recovery of the Pacific Giant Salamander in B.C. is:

To ensure a well-connected, viable, and self-sustaining population of the Pacific Giant Salamander (Dicamptodon tenebrosus) within secure habitat ^Footnote1 throughout its known range ^Footnote2 in Canada where habitat still exists or can be restored.

This long-term goal can be achieved by ensuring effective protection of known populations, conserving and restoring habitat connectivity, and increasing knowledge of habitat requirements and occurrences.

Thus, the short-term goals are:

• to ensure that the current B.C. population of Pacific Giant Salamander is maintained with no further loss of local populations ^Footnote17 (achieve within 5 years); and
• to ensure that patterns of natural population dynamics and dispersal can be maintained or restored within the species' known range (achieve within 5 years).

A change in COSEWIC listing from Threatened to Special Concern might be possible if threats to habitat can be reduced.

The recovery goal assumes that sufficient habitat to maintain a viable population exists within the current geographic range of the species in B.C. Two sources of information support this assumption: the overall distribution of the species is believed to have changed little in recent history; and apparently viable local populations continue to persist in different parts of the range. Quantitative targets are not possible because of uncertainties in estimating the number of connected sub-populations and size of each sub-population needed for establishing a long-term viable population for species persistence.

The COSEWIC status criteria for listing the Pacific Giant Salamander as Threatened included

1. small geographic range (extent of occurrence);
2. small area of occupancy together with continuing decline in extent and/or quality of habitat; and
3. very restricted area of occupancy or number of locations, increasing vulnerability of the population to human activities or stochastic events.

Recovery efforts will not improve the small geographic range, but mitigation of threats at occupied sites can alleviate the decline in extent and quality of habitat and decrease vulnerability of populations, possibly leading to down-listing of the species. Also, inventory of unsurveyed areas within the species' range (only about 20% of potentially suitable habitat has been surveyed) may result in increases to the known area of occupancy.

The recovery objectives focus on the short-term recovery goals but ultimately contribute to achieving the longer-term goal.

The recovery objectives are:

Objective 1: Protect all known local populations including their terrestrial and aquatic habitats within 2 years.

Objective 2: Create or maintain networks of upland and riparian dispersal habitat among and between occupied drainages throughout the species range to reduce fragmentation within 10 years.

Objective 3: Prevent the inadvertent loss of not-yet discovered populations by clarifying distribution of the species and ensuring the occurrence and habitat data are readily accessible within 5 years.

Objective 4: Increase understanding of the habitat needs, life history, population dynamics, and habitat use of the species and to clarify threats facing these populations, so that appropriate conservation measures can be taken and population and habitat targets can be quantified within 5 years.

Objective 5: Actively engage landowners, managers, and users in stewardship activities within 2 years.

Recovery planning table

The broad approaches for recovery of this species consist of the following: habitat protection, management, and stewardship; habitat mapping; population inventories; habitat restoration; population and habitat monitoring; threat clarification; research on life history, population dynamics, and habitat use; and outreach and communication (Table 3). Protecting occupied terrestrial and aquatic habitat and maintaining or enhancing habitat connectivity among streams and stream systems are of highest priority. Other strategies in Table 3 are intended to support habitat protection by filling in data gaps, providing necessary information for management, communicating this information to stakeholders, and collaborating and coordinating with conservation initiatives for other species.

Description of the recovery planning table

Habitat protection, management, and stewardship

Strategies for protecting occupied aquatic and terrestrial habitats are considered urgent. Habitat protection is to focus first on streams and associated terrestrial habitat within productive older forest (>100 years old), as remaining mature and old-growth forest continues to be lost. However, because much of high capability habitat for the species is in lower elevation forest that has been logged or otherwise modified in the past, the focus is also on protecting high-quality occupied habitat in younger, maturing forest in strategic areas, especially in areas with clusters of records of the species. The establishment of forested buffers of sufficient width and large reserve areas is a very important tool in the maintenance of Pacific Giant Salamander populations in managed forests (see review in Appendix 3). Properly designed buffers help maintain the quality of both terrestrial and in-stream habitats and minimize negative edge effects. The main purpose of large reserve areas is to increase habitat connectivity and provide overland dispersal habitat for salamanders within and between drainage systems.

Securing overland dispersal routes merits special consideration when protecting and managing salamander habitat. Where clusters of streams with distribution records and other suitable high-quality habitats occur, protecting or managing the entire subsystem of streams and associated forest is desirable, particularly where older forest remains. Securing overland dispersal routes within at least 50% of occupied sub-drainages (i.e., fourth-order watersheds as per Appendix 1) is recommended through managing forest harvesting and other human activities. However, where opportunities exist, options for similar connectivity at a broader scale among watersheds should also be explored, incorporating existing protected areas into the network whenever possible. Olson et al. (2007) provided a comprehensive review of various spatial patterns of reserves for amphibians in managed headwater forests of the Pacific Northwest of the United States. These options also apply for managing dispersal habitat for the Pacific Giant Salamander habitat in British Columbia.

Habitat mapping

An initial habitat model for the species has been prepared. ^Footnote18 This recovery strategy calls for the refinement and extension of the model, including collecting additional field data on habitat attributes and relative abundance of salamanders at occupied sites. The model is useful for prioritizing survey efforts and contributes towards the delineation of critical habitat.

To help coordination with other conservation initiatives, the creation of a GIS map is needed, showing occurrences of protected areas, special management zones, fisheries restoration projects, and occurrences of other species at risk with overlapping distributions. This map will help in identifying opportunities for connecting habitats, coalescing smaller protected areas into larger units, and ensuring that habitat suitability for the Pacific Giant Salamander is maintained within areas managed for other species.

Population inventories

Less than 20% of potentially suitable streams within the species' Canadian range have been surveyed, and inventories are considered urgent. More accurate information on the species' distribution is needed to protect occupied habitat, refine the existing habitat model, ^Footnote12 and describe critical habitat. It is expected that much of the survey effort can be conducted as part of ground-truthing surveys for the habitat model.

Habitat restoration

Degraded terrestrial and aquatic habitats can often be restored to increase their suitability for salamanders. It is important to identify and take advantage of restoration opportunities as they arise. While results of some habitat restoration measures, such as improving habitat connectivity among streams within logged landscapes, may take years to be realized, other measures can be completed quickly and with relatively little effort once the problem has been identified. Examples of the latter involve replacing or adjusting culverts so that they are accessible to salamanders or removing steep rock embankments along roads at stream crossings to facilitate salamander movements.

Population and habitat monitoring

Very little quantitative information is available on responses of the Pacific Giant Salamander to specific buffer widths extending from each side of a stream and the size and configuration of reserve areas (see Appendix 3). According to the Identified Wildlife Management Strategy guidelines, the linear Wildlife Habitat Area (WHA) for this species consist of a 30 m wide protected core area buffer and an additional 20 m wide management zone buffer, on both sides of the stream reach. Effectiveness monitoring is essential to validate these buffer widths and to adjust them if needed. Before and after studies of buffers of different widths and comparisons of existing buffers with uncut reference sites are recommended.

Habitat needed for dispersal and maintaining metapopulation structure of the salamanders at landscape scales is difficult to study directly but can be investigated indirectly using a genetic approach. Therefore, it is important to expand genetic studies initiated by Curtis and Taylor (2004) for the Pacific Giant Salamander to examine metapopulation dynamics in landscapes with different levels of connectivity. Such analyses can be used to assess the adequacy of different patterns of dispersal habitat within the landscape.

Long-term monitoring sites need to be established in the core and the periphery of the range of this species to assess the impact of climate change. Some climate change induced impacts include changes to stream flow, either increased frequency of droughts or flooding, changes in temperature and over the time scale of decades there could be changes in forest composition which could indirectly affect salamander habitat quality.

Threat clarification

Threat clarification strategies include assessing threats at each site during surveys and monitoring selected habitat indicators at protected sites, such as Wildlife Habitat Areas, and in areas subjected to forestry, micro-hydro developments, or other resource uses. Monitoring habitat indicators is intended to show trends in the quality of salamander habitat over time in areas subjected to different types and intensities of resource use. Introduced sports fish are considered a threat to salamanders, but their distribution within the upper Chilliwack Watershed is largely unknown. It is important to document their distribution patterns and to assess whether they are released in salamander habitat or in adjacent watercourses from where they can access salamander habitat. Fisheries habitat restoration is prevalent within the Chilliwack drainage and potentially affects salamander habitat. Coordination with responsible agencies is needed to evaluate whether these activities are compatible with salamander habitat protection.

Research on life history, population dynamics, and habitat use

Recommended research focuses on filling data gaps in knowledge on the ecology of the species. Suitable nesting sites are potentially a limiting resource for the salamanders and need further investigation. Life history and population dynamics also require further study. This information is needed for population viability modeling and for adequately managing habitat for all life history stages of the salamanders.

Outreach and communication

Effective communication with stakeholders and the public is vital for successful management and stewardship of salamander populations. Recommended strategies include workshops with stakeholders, increasing awareness of the species, its habitat requirements and protection needs among land use planners and managers, and promoting the adoption of best management practices through stewardship. Collaboration and coordination with recovery efforts for other species at risk with overlapping distributions is also essential (see "Recommended Approach for Recovery Implementation").

Performance measures below consist of a combination of procedural measures and assessment of biological outcomes. Performance measures are intended to show whether particular activities were carried out as intended, whereas biological measures address whether desired outcomes for the salamander population have been achieved.

• Percentage of the linear length of occupied streams and associated terrestrial habitat secured through Wildlife Habitat Areas, new protected areas, management plans on existing protected areas, stewardship agreements, or other (specify) means (Objective 1).
• Secure suitable overland dispersal routes among streams and stream systems by managing forest harvesting and other human activities within at least 50% of occupied sub-drainages (i.e., fourth-order watersheds as per Appendix 1) and explore options for connectivity among sub-drainages scored by forest age class (Objective 2).
• Percentage of new streams surveyed for salamanders in comparison with total number of streams with suitable habitat. Clarify occupancy within the known Canadian range of the species by increasing survey coverage to at least 50% of streams containing potential habitat for the salamanders and apply protective measures to streams where the species is found (Objectives 3, 4).
• Persistence of populations at secured sites (Objectives 1, 2).
• Persistence of suitable habitat conditions at secured sites (Objectives 1, 2).
• Increase knowledge of the habitat requirements, population processes, terrestrial movements, threats, and refined habitat model based on above and survey data, so that critical habitats can be accurately described, population and habitat targets can be determined, and ultimately the recovery goal can be met (Objectives 1, 2, 3, 4).
• Number of conservation covenants, stewardship agreements, or written habitat protection contracts, or management plans initiated and completed; number of hectares (ha) of salamander habitat protected by above means (Objective 5).
• Information flow and data management to support habitat protection and management so that Objectives 1 and 2 can be achieved.

Identification of the species' critical habitat

Critical habitat under the federal Species at Risk Act is not proposed for legal identification in this document. For Pacific Giant Salamander, critical habitat ^Footnote19 may include both survival habitat (based on known occurrences) as well as recovery habitat. Additional detailed mapping and consultation work will be required before critical habitat can be proposed. Recovery habitat will be identified through the list of studies to identify critical habitat (below).

Biophysical attributes of critical habitat

The habitat needs of all life stages of the Pacific Giant Salamander must be met for populations to persist. Thus it is recommended that critical habitat will consist of both headwater streams and adjacent terrestrial forest. Occupied streams are typically small and cascading, and may flow through a variety of moist forest types (Farr 1989; Haycock 1991; COSEWIC 2000). Narrow, shaded, mid-gradient streams with coarse rocky substrates and abundant pocket pools form the best aquatic habitat. Neotenic adults require permanent, relatively deep water and often occur at high elevations, or at lower elevations, in large permanent water bodies. Terrestrial adults occupy forested riparian habitats close to streams and require abundant shelter. Based on the biological and habitat needs of the species, the area required for survival is recommended as 50 m core and an additional 30 m management zone area around each side of the stream associated with the capture location (where available) and additional upland habitat to maintain connectivity, dispersal habitat, and meta-population dynamics.

Based on the data available, the best quality habitat and important habitat features for the species are currently defined as (based on Farr 1989; Haycock 1991; COSEWIC 2000; Ovaska et al. 2004 and references therein):

Aquatic habitat: Small, cool, clear, well-oxygenated, moderate- to fast-flowing streams; average wetted width of occupied streams 2.25 m (range: 0.7-10 m); ^Footnote8 streams permanent and with a stable channel (not subject to scouring in spring or drying up in summer); presence of small "pocket" pools in streams; gravel and pebble substrate with refuges large enough to cover the animal.

Terrestrial habitat: Moist, shady forest with western hemlock, western redcedar, and/or Douglas-fir adjacent to streams, such as in older forest; abundant coarse woody debris or other cover on the forest floor, including large logs in advanced stages of decay; suitable nesting sites in or immediately adjacent to stream.

Dispersal habitat: A network of forested stream riparian zones and moist upland forest between streams; shaded conditions, such as in old-growth or mature second-growth forest; abundant coarse woody debris or other cover on the forest floor.

Most of the land base within the Canadian range of the Pacific Giant Salamander is on provincial Crown lands under timber licences. The Identified Wildlife Management Strategy under the B.C. Forest and Range Practices Act provides the main means for protecting and managing salamander habitat on these lands. As of January 2010, 20 Wildlife Habitat Areas (WHAs) have been approved with a minimum of 30 m core and 20 m management zone on either side of the stream reach.

The establishment of forested buffers of sufficient width and large upland reserve areas is a very important tool in the maintenance of Pacific Giant Salamander populations in managed forests (see review in Appendix 3 for details). Properly designed forested buffers along streams help maintain the quality of both terrestrial and in-stream habitats for Pacific Giant Salamanders and minimize negative edge effects. The Recovery Team recommends the protection of at least a 50 m core habitat on each side of an occupied stream with an additional 30 m management zone on each side to reduce edge effects. This buffer width is larger than currently prescribed for WHAs (30 m core with 20 m buffer zone on each side of stream). The effectiveness of these narrower buffers for this species is untested, and data for this and other salamanders indicate that wider buffers are needed both to provide adequate habitat for all segments of the population (adults, sub-adults, and transformed juveniles), and to reduce blowdown and changes in microclimate within the core area.

One study has specifically addressed terrestrial habitat use by this species through following movements of radio-tagged salamanders in British Columbia and Washington State (Johnston 1998; Johnston and Frid 2002). The authors found that although most movements were very close to the stream, the farthest distance that an individual tagged Pacific Giant Salamander moved from the stream edge during the study was 66 m in continuous forest (18 individuals were tagged). Hence the narrower buffers would not accommodate these potentially important long-distance movements. In the United States, movements of the Pacific Giant Salamander up to 400 m from streams have been documented (reviewed in Olson et al. 2007). Furthermore, the British Columbia study followed individual animals for only 3-4 months and involved a relatively few salamanders, most of which were adults; movements of sub-adults have not been studied. In other species of aquatic-breeding salamanders, sub-adults inhabit upland areas farther from aquatic habitats than do adults (Trenham and Shaffer 2005). Sub-adults are extremely important for maintaining population size, demographic structure, and genetic variability, and they represent recruits to the breeding population. Another important consideration is wind-firmness and changes in microclimate (temperature, humidity, wind velocity) on the forest floor within buffer zones. Studies indicate that edge effects on microclimate can extend far into the forest interior, depending on site-specific conditions (Chen et al. 1995; Anderson et al. 2007).

In light of current data on movements of adults, gaps in our knowledge about movements of sub-adults, and pervasiveness of potentially deleterious edge effects, the recovery team recommends a conservative approach and the retention of wider buffers. At the same time, monitoring the effectiveness buffers of different width, including existing narrower buffer zones, is recommended.

With the approved WHAs, the total within the core areas is 38 km (linear; 320 ha), which is approximately 25% of the estimated total known occupied stream lengths (Figure 3; Appendix 2). Existing additional mechanisms of protection include parks and ecological reserves (12.6% of linear stream habitat), and community watersheds (2.3%). Opportunities for protection of salamander habitat also exist within existing special management areas (Special Resource Management Zones, Old Growth Management Areas, and WHAs for other species).

This species also occurs on lands under federal jurisdiction (First Nation Reserves: 1 stream; Department of National Defence properties: 3 sites).

It is important to evaluate the effectiveness of approved Wildlife Habitat Areas (WHAs) on provincial Crown lands and apply for additional WHAs at occupied sites. Habitats at existing protected areas, such as parks, ecological reserves, community watersheds, and special management areas, such as Special Resource Management Zones and Old-growth Management Areas, need to be managed to meet needs of the salamanders before they can be considered secure. Habitat on private lands can be secured through stewardship, including working with municipal and regional governments to achieve habitat protection at landscape and broader levels. Stewardship activities include identification of salamander habitat, adoption of Best Management Practices, designation of Environmentally Sensitive Development Permit Areas, and provision of tax incentives that encourage the establishment of conservation covenants and stewardship agreements.

Private lands comprise only about 9% of the species' Canadian range and are zoned for residential, commercial, and agricultural land uses. However, these areas contain productive low- elevation habitats and hence are very important for the salamanders. Habitat on private lands can be secured through stewardship. Recommended stewardship activities for private lands include communications with municipal and regional governments to include provisions for salamander habitat in land use, community, and development planning and the adoption of Best Management Practices. Options for the province to directly purchase land at key sites should also be explored, especially within the western and northwestern portions of the species' range at low to moderate elevations where development is proceeding at rapid pace.

Several species at risk occur within the range of the Pacific Giant Salamander and use similar habitats. The following species listed by COSEWIC are expected to accrue the greatest benefits:

• Spotted Owl (Strix occidentalis; Endangered, Red-listed), which will benefit from the protection of older forest stands in riparian areas.
• Coastal Tailed Frog(Ascaphus truei; Special Concern, Blue-listed), which has very similar habitat requirements to those of the Pacific Giant Salamander and will benefit from habitat protection and management measures.
• tall bugbane (Actaea elata);Endangered, Red-listed), a plant that overlaps extensively with the Pacific Giant Salamander in distribution and habitat requirements. Many locality records for this species are from forested riparian zones, including several small headwater streams where the Pacific Giant Salamander occurs.
• Mountain Beaver, rufa subspecies (Aplodontia rufa rufa; Special Concern, Blue-listed), overlaps broadly in distribution with the Pacific Giant Salamander. The burrow systems of this species probably provide terrestrial salamanders with underground refuges, foraging sites, and travel corridors.

The following species listed by COSEWIC may also accrue benefits, but their distribution is limited to lower elevation zones:

• Pacific Water Shrew (Sorex bendirii; Endangered, Red-listed), which occupies riparian habitats along ponds and slow-moving creeks and streams.
• Oregon Forestsnail (Allogona townsendiana; Endangered, Red-listed), which occupies lower elevation mixedwood forests. Two locality records for this species are in the vicinity of Pacific Giant Salamander records.

Other species likely to benefit from the retention of older forest and its attributes and/or forested stream buffers include the Red-legged Frog (Rana aurora; Special Concern, Blue-listed), Marbled Murrelet (Brachyrampus marmoratus; Threatened, Red-listed), and Trowbridge's Shrew (Sorex trowbridgii; not assessed by COSEWIC, Blue-listed). Negative effects on prey species, such as Tailed Frog tadpoles and aquatic invertebrates, are possible in localized areas. However, giant salamanders have a long evolutionary history of coexistence with these organisms, and any negative effects will probably be greatly offset by benefits accrued from habitat management and protection.

Riparian ecosystems along headwater forest streams will benefit from habitat protection and restoration under the Pacific Giant Salamander recovery strategy. Species other than those already mentioned, such as semi-aquatic mammals (otters, mink, weasels, shrews), birds (American Dipper (Cinclus mexicanus), Harlequin Duck (Histrionicus histrionicus), songbirds, raptors), and aquatic invertebrates, are all likely to benefit. Moist, western redcedar dominated ecosystems with skunk cabbage and other moisture-loving plants are unique components of the Pacific rainforest and can be severely affected by canopy removal and associated drying of the forest floor. These ecosystems and their associated faunas are likely to benefit from the management and protection of riparian habitats for the Pacific Giant Salamander.

The following is a brief outline of potential and known socioeconomic cost and benefits.

The recovery team identifies several positive socio-economic benefits of Pacific Giant Salamander recovery related to

1. biodiversity and sustainable resource management,
2. species at risk legal obligations and jurisdictional independence,
3. international trade and cooperation,
4. forest certification,
5. scientific interest,
6. First Nations interests, and
7. eco-tourism.

Potential costs identified include

1. potential future reductions in timber harvest,
2. costs of increased private land protection and management,
3. costs of increased government management, and
4. increased resources for ecological research.

Forestry is the main industry adversely affected by recovery measures for the Pacific Giant Salamander. Additional impacts to the forestry sector are anticipated because it is unlikely that all essential habitat can be protected under existing 1% policy limits set for timber supply impacts as the budget is also used to manage other species.

Social benefits resulting from improving stream quality and maintaining streamside forest habitats for the Pacific Giant Salamander include the following:

• improvement of downstream habitat for commercial and sports fish within the Chilliwack and Lower Fraser Watersheds;
• improvement in water quality for consumption by humans and livestock;
• reduction in erosion hazards in residential areas;
• increased opportunities for low impact recreational activities such as hiking; and
• improvement in ecosystem services, including maintenance of biodiversity, forest productivity, hydrological patterns, and clean water

Many opportunities exist for integrating the implementation of the Pacific Giant Salamander recovery into other recovery or conservation efforts and the sharing of information and resources to benefit multiple species and ecosystems of conservation interest. This can be in part implemented through the South Coast Conservation Program. The recovery team for the Pacific Giant Salamander should co-operate with recovery teams for other species at risk including tall bugbane, Spotted Owl, Coastal Tailed Frog, Mountain Beaver, rufa subspecies, Pacific Water Shrew, and Oregon Forestsnail. Recovery initiatives such as habitat protection, management, and restoration can be potentially improved for all species by pooling resources whenever possible. For example, by enlarging the size of a protected area to include multiple species at risk, the area would be more secure and less susceptible to fragmentation and edge effects. Co-operation would be enhanced by creating a centralized database for species of risk. Coordination of Species at Risk activities is also important to ensure that no harm is done inadvertently to other species.

Effective co-ordination of the many government agencies, programs, and conservation groups involved in the Chilliwack Watershed will benefit the recovery of this and other species and ecosystems at risk. This co-ordination can also be achieved through organizations such as the South Coast Conservation Program. It is important that landscape level planning and activities incorporate multi-species recovery objectives. Landscape level mechanisms that can help achieve multi-species recovery objectives include the Forest and Range Practices Act (FRPA), Community Watershed protection, Chilliwack River Watershed Strategy, and Land Use Planning initiatives of the Fraser Valley Regional District. FRPA is an important program available to protect and manage multiple species at risk in the Chilliwack Watershed. However, allowable timber harvesting land base impacts of conservation action (e.g., 1% Identified Wildlife budget) will likely need to be increased to accommodate conservation of listed identified wildlife. Government agencies at the federal, provincial, and local level all play a role in the recovery of the Pacific Giant Salamander. Some federal lands managed by the Department of National Defence and First Nations contain this and other species at risk, and the Department of Fisheries and Oceans undertakes numerous watershed restoration projects that can affect species at risk. At the provincial level, the MoE, MoFR, and B.C. Parks all have different roles to play in achieving recovery goals, and influence the majority of habitat occupied by the Pacific Giant Salamander and other species at risk in the Chilliwack Watershed. Local and regional governments, including the Fraser Valley Regional District, can help recovery efforts where the Pacific Giant Salamander occurs on private lands and lands under their jurisdiction in the western portion of the Chilliwack Watershed.

An action plan is being drafted and is expected to be completed within 2 years from the posting of the recovery strategy.

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The entire watershed is a fourth-order watershed. Sub-basins A, B, and C are third-order watersheds.

From: Figure 3-1. Stream ordering technique. The entire watershed is a fourth-order watershed. Sub-basins A, B, and C are third-order watersheds.

There are 20 approved Wildlife Habitat Areas for Pacific Giant Salamander (as of January 2010). These are based on a 30 m core and 20 m management zone on either side of the stream reach. Connectivity implemented through upland zones.

The establishment of forested riparian buffers and large reserve areas is a very important tool in the maintenance of Pacific Giant Salamander populations in managed forests, including the Chilliwack Watershed. However, there is very little quantitative information on the response of the Pacific Giant Salamander to specific buffer widths extending from each side of a stream and the size and configuration of reserve areas. The type of forested buffers and reserves required will vary according to site characteristics such as terrain, elevation, hydrology, forest type, and susceptibility to windthrow. Properly designed buffers help to maintain the quality of both terrestrial and in-stream habitats and minimize negative edge effects. Buffers usually consist of a core area of undisturbed vegetation and an outer management zone designed to maintain the microclimatic conditions of the core area. If buffers are too narrow, the forest floor habitat used by salamanders will be subjected to temperature increases and desiccation as a result of increased solar radiation, wind penetration, and windthrow. In-stream habitats may also deteriorate as a result of temperature increases, shade reduction, and increased levels of siltation or pollution. This is especially important for cold water dependent species such as giant salamanders (Bury 2008). Buffers should also be continuous above and below occupied stream stretches to minimize downstream siltation and flooding, maximize connectivity of habitats, and provide travel routes to re-occupy new stretches of stream.

The main purpose of large reserve areas is to increase habitat connectivity and provide overland dispersal habitat for salamanders within and between drainage systems. Reserves should be configured so as to facilitate the re-colonization of previously occupied areas, colonization of new areas, and genetic interchange between local populations. They should also serve to buffer large areas of stream and riparian habitat from the potentially catastrophic effects of wildfire, flooding, windthrow, and climate change. Reserve areas also provide reference sites for research and effectiveness monitoring studies. Reserve areas should be large enough to cover the entire length of several tributary streams within a drainage. They should be continuous with existing protected areas whenever possible and be distributed widely over the species range. Olson et al. (2007) provide a comprehensive analysis of various spatial patterns of reserves for amphibians in managed headwater forests of the Pacific Northwest (see Figure 3c-g in Olson et al. 2007 for examples of reserve designs). One important feature for maintaining connectivity between local populations is to ensure that reserves from adjacent drainages extend all the way to the ridgeline and meet each other.

Forested buffers around streams provide essential foraging, refuge, and overwintering habitat for terrestrial adult Pacific Giant Salamanders and help maintain suitable in-stream conditions for larvae and neotenes. They also facilitate dispersal movements along streams. Increasing the width of forest buffers helps maintain the microclimate of terrestrial and in-stream habitats similar to undisturbed reference sites (Chen et al. 1995; Brosofske et al. 1997; Johnston and Frid 2002; Anderson et al. 2007). The cool moist conditions created by a stream and associated riparian vegetation are known to permeate upslope into upland habitat and create a microclimate suitable for terrestrial adults (Olson et al. 2007). In Oregon, Veseley and McComb (2002) reported that uncut riparian forest contained more canopy, fern, moss, and large-diameter log cover than did buffer strips (medium width of 21 m) along streams. Chen et al. (1995) found that forest strips had higher wind velocities, and greater variations in temperature and humidity than did forest interiors and that this influence of adjacent clearcuts extended 240 m or more into uncut forest. Anderson et al. (2007) recommend that the entire riparian vegetation zone be protected and that buffers extend to topographic breaks to be effective in buffering the effects of adjacent clearcuts or thinned forests.

The width of forest buffers should encompass the seasonal habitat requirements and movements of Pacific Giant Salamanders and protect these core areas of activity from adverse edge effects. Several studies in Oregon have found the Pacific Giant Salamander up to 400 m from stream edges (reviewed in Olson et al. 2007). During a radio-telemetry study in the Chilliwack and Nooksack Watersheds, Johnston and Frid (2002) found that the maximum distance of a Pacific Giant Salamander from the stream edge was 66 m in forest, 22 m in buffered areas, and 19 m in clearcuts, based on radio-telemetry techniques. Ninety-four percent of salamanders (16/17) in forested areas stayed within 25 m of the stream edge, during a 3- to 4-month period. The behaviour of salamanders along streams with 20-30m buffers was similar to forested habitats; however, only a small sample of salamanders (n = 7) were radio-tagged in areas with buffers. This study suggests that a core area of about 25-30 m would be required to account for most movements. However, to minimize adverse edge effects, an additional management zone is required to maintain the integrity of the core area over the long term and to account for occasional longer distance movements.

The width of the core area and management zone required is dependent on the characteristics of the site such as forest type, terrain, and susceptibility to windthrow. In Oregon, Stoddard and Hayes (2005) found that the presence of headwater stream populations of Pacific Giant Salamanders were positively associated with sections of streams that had at least a 46 m band of forested habitat on each side of the stream. Also in Oregon, Vesely and McComb (2002) reported that 80% of observations of three aquatic breeding salamanders, including the Pacific Giant Salamander, occurred within 20 m of the stream edge in areas with buffer zones ranging from 0 to 64 m. They estimated that that a buffer of 43 m would support salamander abundance (10 species in total) similar to that observed in uncut forest. They also recommend that a management zone of restricted harvesting may be required to protect against edge effects. In the eastern United States, Crawford and Semlitsch (2007) found that 95% of observations of four stream-breeding salamanders occurred within 27 m of the stream edge. They recommend an additional 50 m forested zone to reduce edge effects, resulting in a total buffer of 77 m on each side of the stream. Harper et al. (2008) conducted computer simulations on populations of pond-breeding spotted salamanders occupying forest buffers of different widths in the eastern United States. For buffer widths of 30 m or less, they predicted that survival rates would decline by 5% annually, leading to a 94% population decline and a 29% probability of extinction in 20 years. A buffer with of 100-165 m around breeding ponds was recommended to achieve a 95% probability of persistence of the population.

There is an urgent need to monitor the effectiveness of different buffer widths along and sizes of reserve areas in the Chilliwack drainage so that future protective measures can be adjusted if required. Before and after studies and comparisons of existing buffers with uncut reference sites are recommended.