Oregon spotted frog (Rana pretiosa) recovery strategy 2015: chapter 1

Official title: Recovery Strategy for the Oregon Spotted Frog (Rana pretiosa) in Canada - 2015

Part 1 – Federal Addition to the "Recovery Strategy for the Oregon Spotted Frog (Rana pretiosa) in British Columbia", prepared by Environment Canada.

Species at Risk Act
Recovery Strategy Series
Adopted under Section 44 of SARA

Oregon Spotted Frog

Oregon Spotted Frog
2015

Document Information


Cover illustration: © Kelly McAllister

Cover photo: Management Plan for the McCown's Longspur

Recommended citation

Environment Canada. 2015. Recovery Strategy for the Oregon Spotted Frog (Rana pretiosa) in Canada. Species at Risk Act Recovery Strategy Series. Environment Canada, Ottawa. 21 pp. + Annex.

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

Également disponible en français sous le titre
« Programme de rétablissement de la grenouille maculée de l’Oregon (Rana pretiosa) au Canada »

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

Under the Accord for the Protection of Species at Risk (1996), the federal, provincial, and territorial governments agreed to work together on legislation, programs, and policies to protect wildlife species at risk throughout Canada.

In the spirit of cooperation of the Accord, the Government of British Columbia has given permission to the Government of Canada to adopt the "Recovery Strategy for the Oregon Spotted Frog (Rana pretiosa) in British Columbia" (Part 2) under Section 44 of the Species at Risk Act (SARA) . Environment Canada has included an addition (Part 1) which completes the SARA requirements for this recovery strategy.

Part 1 - Federal Addition to the "Recovery Strategy for the Oregon Spotted Frog (Rana pretiosa) in British Columbia", prepared by Environment Canada

Preface

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

The Minister of the Environment is the competent minister for the recovery of the Oregon Spotted Frog and has prepared the federal component of this recovery strategy (Part 1), as per section 37 of SARA. It has been prepared in cooperation with the Canadian Oregon Spotted Frog Recovery Team and the Province of British Columbia. 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 led the development of the attached recovery strategy for the Oregon Spotted Frog (Part 2) in cooperation with Environment 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 Canada, or any other jurisdiction alone. All Canadians are invited to join in supporting and implementing this strategy for the benefit of the Oregon Spotted Frog 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 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 the recovery strategy identifies critical habitat, there may be future regulatory implications, depending on where the critical habitat is identified. SARA requires that critical habitat identified within federal protected areas be described in the Canada Gazette, after which prohibitions against its destruction will apply. For critical habitat located on federal lands outside of federal protected areas, the Minister of the Environment must either make a statement on existing legal protection or make an order so that the prohibition against destruction of critical habitat applies. For critical habitat located on non-federal lands, if the Minister of the Environment forms the opinion that any portion of critical habitat is not protected by provisions in or measures under SARA or other Acts of Parliament, and not effectively protected by the laws of the province or territory, SARA requires that the Minister recommend that the Governor in Council make an order to extend the prohibition against destruction of critical habitat to that portion. The discretion to protect critical habitat on non-federal lands that is not otherwise protected rests with the Governor in Council.

Additions and Modifications to the Adopted Document

The following sections have been included to address specific requirements of SARA that are either not addressed, or which need more detailed information, in the Recovery Strategy for the Oregon Spotted Frog (Rana pretiosa) in British Columbia (Part 2 of this document, referred to henceforth as "the provincial recovery strategy"). In some cases, these sections may also include updated information or modifications to the provincial recovery strategy for adoption by Environment Canada.

1. Species Status Information

Legal Status: Endangered under Schedule 1 of SARA (2003).

Table 1. Conservation status of the Oregon Spotted Frog (from NatureServe 2011 and B.C. Conservation Framework 2010).
Global (G) RankNoteaof Table 1 National (N) RankNoteaof Table 1 Sub-national (S) RankNoteaof Table 1 COSEWIC Status B.C. List B.C. Conservation Framework
G2 (2011) N1 (2011) British Columbia (S1), Washington (S1), Oregon (S2), California (S1) Endangered (2011) Red Highest priorityNotebof Table 1: 1,
under GoalsNotecof Table 11 and 3

It is estimated that the Canadian range of this species comprises less than 5% of its global range (COSEWIC 2011).

2. Population and Distribution Objectives

Environment Canada supports the provincial Population and Distribution Goal and adopts it as the Population and Distribution Objective for the Oregon Spotted Frog. The Population and Distribution Goal and Rationale, outlined in sections 5.1 and 5.2 of the provincial document, and provided here for reference, are as follows:

"5.1 Population and Distribution Goal

The population and distribution goal (within 10 years) is

To restore, maintain and where feasible expand extant Oregon Spotted Frog populations, and establish six or more additional self-sustaining populations in B.C.

5.2 Rationale for the Population and Distribution Goal

There are only four Oregon Spotted Frog populations known in B.C. with less than 350 individuals. One of the populations (Maintenance Detachment Aldergrove) is possibly on the brink of extirpation. An additional four populations are known to be extirpated. Each of the extant populations is isolated from the other populations, and the probability of gene flow between populations, or recolonization is extremely low. Suitable habitat within the range of the Oregon Spotted Frog has been lost and degraded over time, largely as a result of land modification for agricultural or urban development. Unless additional populations are created through re/introduction to new and/or restored sites, the probability of species extirpation from B.C. is considered high. The immediate goal is to prevent extirpation.

Habitat use pressures within the Oregon Spotted Frog range and the presence of introduced species constrains the number of available new or reintroduction sites. Although 13 potential sites are presented in Table 4Footnote1, further investigation will likely reveal that several of these sites are not suitable (e.g., may be too degraded to be effective for recovery). With this in mind, the goal was set to establish 6 or more populations over the next 10 years. This would result in the number of occupied locations increasing from 4 to a minimum of 10 locations. A minimum number of breeding adults at each location is needed to sustain viable populations. Until more specific information is available, the population objective is 200 breeding adults per location. It is recognized however, that the carrying capacity may limit what is achievable and as a result targets will vary by location. In addition, it should be noted that the distribution objective may slightly expand the species' range beyond the historic sites, due to introductions into suitable habitat in the Fraser Valley that is not known to have been occupied in the past.

In the time it takes to establish new or reintroduced populations, existing individual populations must remain stable or increase. This will hopefully be achieved through threat mitigation and population augmentation. If successful, extirpation of the Oregon Spotted Frog will be prevented. It may be possible for the COSEWIC designation to be upgraded from Endangered to Threatened, but further improvement in conservation status is not expected given the limited amount and fragmented nature of suitable habitat remaining for this species."

3. Critical Habitat

This section provides information that augments, replaces, or references "Information on habitat needed to meet recovery goal" (Section 7) in the provincial recovery strategy, as identified in each subsection.

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.

3.1 Identification of the Species' Critical Habitat

This section replaces "Description of Survival/Recovery Habitat" (Section 7.1) in the provincial recovery strategy.

Critical habitat for the Oregon Spotted Frog is identified in this recovery strategy to the extent possible, based on the best available information. It is recognized that the critical habitat identified below is insufficient to achieve the population and distribution objectives for the species because it does not include habitat for the six or more additional populations that must be established to meet the population and distribution objectives.  Critical habitat was not identified at historical or candidate introduction locations because the habitat is currently unsuitable for the frog and/or the Canadian Oregon Spotted Frog Recovery Team (the "recovery team") has not confirmed which sites are suitable for (re)introduction. Additional work is required prior to finalizing the list of introduction locations (P. Govindarajulu pers. comm. 2011, M. M. Pearson pers. comm. 2011, K. Welstead pers. comm. 2011). A schedule of studies (Section 3.2) has been developed to provide the information necessary to complete the identification of critical habitat that will be sufficient to meet the population and distribution objectives. The identification of critical habitat will be updated when the information becomes available, either in a revised recovery strategy or action plan(s).

The recovery team has developed a definition of habitat critical to the survival of Oregon Spotted Frog ("survival habitat") by identifying important biophysical attributes of survival and recovery habitat and by identifying a process to geospatially describe the necessary survival and recovery habitat. The process and areas of survival habitat identified by the recovery team are outlined in "Procedure to describe survival and recovery habitat" (Section 7.1.3) in the provincial recovery strategy. The criteria for including habitat as critical habitat are outlined below, and capture the five process points outlined in the provincial Description of Survival/Recovery Habitat, while providing greater certainty about the location of Critical Habitat. The critical habitat identification also excludes one element of the provincial survival habitat identification: the critical habitat identification does not include an increase in width when impermeable surfaces are present within the critical habitat area. The intent of creating this area was to maintain hydrology and water quality. However, as it would be extremely difficult to determine exactly where this additional critical habitat area is located, this element of the survival/recovery habitat description was not included. 

Critical habitat for Oregon Spotted Frog includes all habitats that meet any of the following criteria:

  1. All occupied habitat;

    Criterion: the areas of the wetland and/or watercourses where any life stage (egg, juveniles, adults, larvae/tadpoles) of Oregon Spotted Frog occurs or has been known to occur.
  2. All other suitable habitat in the watershed where it is feasible for the Oregon Spotted Frog to colonize, and the connecting habitat;

    Criteria:
    1. all habitat within the same watershed that is suitable for Oregon Spotted Frog (e.g., meets the biophysical attributes required by the species (Section 3.1.1); or is identified as suitable using techniques such as habitat suitability mapping), where:
      • the habitat has an aquatic connection (perennial, ephemeral or intermittent; e.g. water bodies, wetlands, ponds, ephemeral pools, seeps, streams, areas of seasonal flooding, and ditches) to occupied habitat (criterion 1); and
      • the habitat is within 3 km (straight-line distance) of occurrence records, and < 260 m in elevation
    2. all other aquatic habitat (perennial, ephemeral or intermittent; e.g. water bodies, wetlands, ponds, ephemeral pools, seeps, streams, areas of seasonal flooding, and ditches, except for the Fraser River main stem) connected to occupied habitat (criterion 1) where:
      • the habitat is within 3 km (straight-line distance) of occurrence records, and < 260 m in elevation
    3. isolated patches (those without an aquatic connection) of a habitat type that is suitable for Oregon Spotted Frog (e.g., meets the biophysical attributes required by the species (Section 3.1.1); or is identified as suitable using techniques such as habitat suitability mapping) where:
      • the habitat is within 400 m (straight-line distance) of aquatic habitat (criterion 2b) or other occupied or suitable habitat (criteria 1 or 2a); and
      • the habitat is within 3 km (straight-line distance) of occurrence records, and is < 260 m in elevation.
  3. All other areas that are required to maintain the attributes of the Oregon Spotted Frog’s habitat (i.e., the quality and quantity of water).

    Criteria:
    1. All types of groundwater flow (e.g. watercourses, intermittent streams, springs or seeps, discharge areas, up-wellings), identified to their headwaters, that influence the water quantity or quality of:
      • the occupied habitats (criterion 1), or
      • other suitable habitats in the watershed where it is feasible for the Oregon Spotted Frog to colonize (criterion 2).

        The areas of groundwater flow identified up to their headwaters may extend > 3 km (straight-line distance) from occurrence records and > 260 m in elevation
    2. A 45 m wide area of critical habitat, measured from the high water markFootnote2, immediately adjacent to habitats identified by criterion 1 and criterion 2. Areas of impermeable surfaces (e.g. roads, parking lots, buildings) within the 45 m wide area are not considered critical habitat. 
       
    3. An area of critical habitat, measured from the high water mark, immediately adjacent to all types of groundwater flow identified by criterion 3a. The width of the areas depends on the surrounding dominant vegetation and land use:
      • If the surrounding dominant land use is and will remain forestry, the strip of area is 30 m wide on each side of the groundwater flow. 
      • If the surrounding dominant land use is agricultural or urban (not forestry), or in harvested forest areas, the strip of area is 45 m wide on each side of the groundwater flow.

For rationales and references to support these criteria, see "Procedure to describe survival and recovery habitat" (Section 7.1.3) in the provincial recovery strategy.  In addition to the information in the provincial recovery strategy about riparian areas removing chemicals such as herbicides, it should be noted that riparian areas can reduce the amount of sediment that reach the waterway, which can help maintain the abundance and species richness of amphibian communities (Vesely and McComb 2002, Rashin et al. 2006, Crawford and Semlitsch 2007, Peterman and Semlitsch 2008).  Peterman and Semlitsch (2008) recommended retaining a 30 m forested zone around streams to reduce the input of sediment into the waterway. Other studies on amphibian populations also recommend the retention of a 30 m zone to preserve the characteristics of the resident amphibian community (e.g., Crawford and Semlitsch 2007).

Critical habitat is identified around four known occupied locations of Oregon Spotted Frog in the lower mainland of British Columbia: Aldergrove, Mountain Slough, Maria Slough, and Morris Valley. The areas containing critical habitat for the Oregon Spotted Frog are presented in Appendix 1, Figures A1 to A5.  The shaded yellow polygons depict areas where the criteria described in this section are met, and represent critical habitat, except where areas of impermeable surfaces occur.  The 10 km x 10 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.

3.1.1. Biophysical attributes of critical habitat

The Oregon Spotted Frog is a wetland/marsh specialist that prefers floodplain wetlands, side channels, and sloughs associated with permanent waterbodies.  These aquatic habitats generally have good solar exposure with low to moderate amounts of cover by emergent vegetation (25–50%; Watson et al. 2003), and silty, rather than gravelly substrate.  Nearby riparian vegetation moderates the microclimate, hydrology, and water quality in the aquatic habitat.  The structural attributes of native emergent and submergent vegetation also influences habitat suitability (Pearl and Hayes 2004).

Habitat requirements are divided into three life-seasons: breeding (oviposition) and early larval habitat, active summer habitat, and overwintering habitat.  Dispersal/connective habitat is required to link the three main habitat types during late spring and fall.  Water quality, maintained by limiting the introduction of fertilizers, pesticides, and sediments into watercourses and wetlands, is a requirement in all habitat types.

Breeding and early larval habitat:

  • areas that experience shallow inundation (<26 cm deep) in the spring (Pearl and Hayes 2004);
  • are >3° C in March/April (C. Bishop, unpubl. data, 2005, 2007); and
  • contain indigenous aquatic vegetation (e.g., rushes, sedges, grasses, pondweeds, buttercups) or moderate amounts of Reed Canarygrass (Phalaris spp.).

Active Season (summer) habitat:

  • wetlands that are >40 cm deep (R. Haycock, unpubl. data, 2001–2002, Watson et al. 2003); and
  • contain moderately dense, structurally diverse submergent, emergent, and floating vegetation (Licht 1969, 1986a,b; McAllister and Leonard 1997, Popescu 2012).

Over-winter habitat:

  • springs, seeps, or low-flow channels that do not freeze in the winter and have more stable levels of dissolved oxygen than other areas (Pearl and Hayes 2004); or
  • in deeper water, beaver dams or areas of dense submerged vegetation (Hayes et al. 2001, Watson et al. 2003, Chelgren et al. 2006, Govindarajulu 2008, Pearson 2010, COSEWIC 2011).

Dispersal/connective habitat:

  • any aquatic habitat not part of the Fraser River main stem, whether permanent or ephemeral, that connects the three main habitat types during late spring and fall.

3.2. Schedule of Studies to Identify Additional Critical

This section augments "Information on habitat needed to meet recovery goal" (Section 7) in the provincial recovery strategy.

To meet the population and distribution objectives for Oregon Spotted Frog, studies are required to identify additional critical habitat for the species. The following schedule of studies (Table 2) outlines the activities required to identify additional critical habitat.

Table 2. Schedule of studies required to identify additional critical habitat for the Oregon Spotted Frog.

  • Description of activity
    • Identify locations suitable for the identification of critical habitat.
      • Activities may include:
        • Conducting surveys for previously undiscovered populations
        • Identifying suitable introduction locations
        • Conducting threat assessments at each site
        • Identifying rehabilitation/mitigation measures necessary to make the site suitable
      • Outcome/rationale:
        • Critical habitat for Oregon Spotted Frog is based on occurrence data. The population and distribution objectives for the species require that at least six additional populations of Oregon Spotted Frog must be discovered or (re)established. To support this objective, activities to identify areas suitable for the identification of critical habitat must be conducted.
      • Timeline:
        • 2015-2022
      • Status:
        • Ongoing
    • Assess habitat and identify critical habitat at six or more additional locations as sites become suitable through habitat rehabilitation, threat mitigation, or the introduction or discovery of Oregon Spotted Frogs.
      • Activities may include:
        • Identify habitat types at the location using orthoimagery and/or ground surveys and assess them as to their suitability for Oregon Spotted Frog
        • Identify all habitats at the site that meet the criteria for critical habitat
      • Outcome/rationale:
        • In order to support the population and distribution objective to restore, maintain and where feasible expand extant Oregon Spotted Frog populations, the habitat at each location must be assessed and critical habitat identified to protect the occurrences.
      • Timeline:
        • 2015-2022
      • Status:
        • Habitat will be assessed and critical habitat identified as each site becomes suitable

3.3 Examples of Activities Likely to Result in Destruction of Critical Habitat

This section replaces "Specific Human Activities Likely to Damage Survival/Recovery Habitat" (section 7.2) in the provincial recovery strategy.

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 3 include those likely to cause destruction of critical habitat for the species; destructive activities are not limited to those listed. Additional information on the negative effects of these activities is provided in "Description of the Threats" (Section 4.2) in the provincial recovery strategy.

Table 3. Examples of activities likely to result in destruction of critical habitat for Oregon Spotted Frogs.

  • Activity:
    • Hydrological modifications (e.g., ditching / channelling, culverting, ditch cleaning, exposure of bedrock through mining operations, drawdown, active removal of beaver dams [but excepting natural beaver dam-building])
      • Description of how activity would destroy critical habitat:
        • Hydrological modification within or outside the area of critical habitat can result in water depths, temperatures, and flow rates that are outside the range required for successful breeding, dispersal, and / or summer and winter survival. The timing of peak flows / water depths and temperatures is critical to the function of the different seasonal habitat types, so destruction can result when activities modify these parameters to a point where seasonal requirements are not met.
      • Relationship to other activities likely to result in destruction?
        • Yes, changes in water source (from ground to surface) can result in greater inputs of pollutants and sediments into watercourses and wetlands.
      • Timing considerations:
        • Applicable at all times. Retaining natural water levels is important for populations of Oregon Spotted Frog, particularly during: the period between oviposition and hatching of tadpoles; over-winter during the coldest period; and in areas that are required to support oviposition, over-wintering, foraging or dispersal.
    • Release of pollutants into watercourses or wetlands (e.g., runoff or spray of pesticides or fertilizers, runoff of manure stored adjacent to habitat, direct input of manure/urine by cattle or livestock, release of leachate from mining operations)
      • Description of how activity would destroy critical habitat:
        • Release of pollutants within or outside the area of critical habitat can result in changes in water chemistry leading to loss of water quality required for survival and successful reproduction.
      • Relationship to other activities likely to result in destruction?
        • No
      • Timing considerations:
        • Applicable at all times.
    • Inputs of sediment into watercourses or wetlands (e.g., forest harvest within critical habitat areas, allowing cattle access to riparian areas, mechanical or chemical removal of riparian vegetation)
      • Description of how activity would destroy critical habitat:
        • Sedimentation within or outside the area of critical habitat can directly affect water quality and modify channel structure, resulting in sediment levels and water depths outside the range required for successful breeding and/or summer and winter survival.
      • Relationship to other activities likely to result in destruction?
        • Yes, the build-up of sediment in the watercourse / wetland or the watercourses that input water/materials to the watercourse / wetland can lead to large runoff events with a resulting sudden influx of pollutants from the surrounding area.
      • Timing considerations:
        • Applicable at all times.
    • Partial or total removal of natural riparian vegetation around watercourses or wetlands (e.g., forest harvesting, urban or agricultural conversion, linear developments, allowing cattle access to riparian areas)
      • Description of how activity would destroy critical habitat:
        • Natural riparian vegetation plays an important role in moderating microclimate and hydrology. Removal of natural riparian vegetation within the area of critical habitat can result in water temperatures, depths, and flow rates/patterns that are outside the range required for successful breeding and/or summer and winter survival.
      • Relationship to other activities likely to result in destruction?
        • Yes, removal of riparian vegetation can also reduce soil stability, leading to bank erosion and increased sedimentation. Removal of riparian vegetation also effects surface permeability, which increases the rate at which pollutants enter wetlands / watercourses. Loss of natural riparian vegetation also facilitates invasion by exotic plant species.
      • Timing considerations:
        • Applicable at all times.
    • Partial or total removal of natural emergent or submergent vegetation (e.g., allowing cattle access to riparian areas, mechanical or chemical removal of emergent / submergent vegetation)
      • Description of how activity would destroy critical habitat:
        • Removal of natural emergent or submergent vegetation within the area of critical habitat can result in densities below the range required for successful breeding and / or summer and winter survival.
      • Relationship to other activities likely to result in destruction?
        • No
      • Timing considerations:
        • Applicable at all times.
    • Introduction of semi-aquatic exotic plant species (e.g., Reed Canarygrass [Phalaris arundinacea])
      • Description of how activity would destroy critical habitat:
        • Introduction of semi-aquatic exotic plant species, which grow in greater densities than native semi-aquatic plant species, can result in emergent and submergent vegetation densities outside the range required for successful breeding and/or summer and winter survival. Introduction of exotic plants within or outside the area of critical habitat could destroy critical habitat.
      • Relationship to other activities likely to result in destruction?
        • No
      • Timing considerations:
        • Applicable at all times.
    • Installation of impassable barriers (e.g., impassable culverts, dams, roads)
      • Description of how activity would destroy critical habitat:
        • Installation of impassable barriers within the area of critical habitat leads to elimination of access between breeding, summer, and winter habitats, which results in loss of habitat function and reduced gene flow.
      • Relationship to other activities likely to result in destruction?
        • Yes, installation of barriers can affect not only movement of Oregon Spotted Frogs, but also hydrology, resulting in water depths, temperatures, and flow rates that are outside the range required for successful breeding, dispersal, and / or summer and winter survival.
      • Timing considerations:
        • Applicable at all times.

4. Statement on Action Plans

One or more federal action plans will be posted on the Species at Risk Public Registry by 2020.

5. Effects on the Environment and Other Species

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 goals and targets (FSDS).

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 provincial recovery strategy notes that recovery actions for Oregon Spotted Frog are unlikely to have any negative effects on non-target species or communities within its range, and may benefit other species at risk. The Oregon Spotted Frog uses similar areas to the Salish Sucker (Catostomus catostomus), the Western Painted Turtle (Pacific Coast population)(Chrysemys picta), the Oregon Forestsnail (Allogona townsendiana), and the Pacific Water Shrew (Sorex bendirii), which are listed as Endangered under SARA; the Red-legged Frog (Rana aurora), Western Toad (Anaxyrus boreas),  Vancouver Island Beggarticks (Bidens amplissima), and Great Blue Heron fannini subspecies (Ardea herodias fannini), which are listed as Special Concern under SARA; as well as the American Bittern (Botaurus lentiginosus) and Green Heron (Butorides virescens), which are considered provincially to be of Special Concern. The site-level details of these species' habitat requirements may differ.

Recovery actions for Oregon Spotted Frog may include habitat protection of the wetland and surrounding watercourses and habitat that influence conditions in the wetlands, removal of exotic invasive species such as reed canarygrass and American Bullfrogs (Lithobates catesbeianus), habitat creation of wetland habitat, as well as other activities with the goal of enhancement or restoration of habitat condition and function. These actions will likely have a positive impact on the native flora and fauna that live in or visit the wetlands and associated habitats.

6. References

Canadian Oregon Spotted Frog Recovery Team. 2011. Recovery strategy for the Oregon Spotted Frog (Rana pretiosa) in British Columbia. Prepared for the B.C. Ministry of Environment, Victoria, B.C.. 68 pp.

Chelgren, N.D., C.A. Pearl, J. Bowerman, and M.J. Adams. 2006. Oregon Spotted Frog (Rana pretiosa) movement and demography at Dilman Meadow: implications for future monitoring. U.S. Geological Survey, Reston, VA.

COSEWIC. 2011. COSEWIC assessment and status report on the Oregon Spotted Frog Rana pretiosa in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. xi + 47 pp.

Craig, V. 2008. Proposed partial survival habitat identification for Oregon Spotted Frog (Rana pretiosa) – DRAFT. Report prepared by Vanessa Craig, Ph.D., R.P.Bio, EcoLogic Research, for the Oregon Spotted Frog Recovery Team. 53 pp.

Crawford, J.A., and R.D. Semlitsch. 2007. Estimation of core terrestrial habitat for stream-breeding salamanders and delineation of riparian buffers for protection of biodiversity. Conservation Biology 21:152-158

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. Min. Environ., Victoria, B.C.Wildlife Report No. R-28.

Hallock, L. and S. Pearson. 2001. Telemetry study of fall and winter Oregon Spotted Frog (Rana pretiosa) movement and habitat use at Trout Lake, Klickitat County, Washington. 36 pp. Cited in Pearl and Hayes (2004) and Cushman and Pearl (2007).

Hawkes, V. C. 2009. Salish Sucker (Catostomus sp.) and Oregon Spotted Frog (Rana pretiosa) habitat investigations and effluent review at Maintenance Detachment Aldergrove with a proposed survival habitat delineation for Oregon Spotted Frog. Unpublished report by LGL Limited, LGL Project EA3132 for Public Works and Government Services Canada, Victoria, B.C. 67p + Appendices.

Hawkes, V.C. 2010. Oregon Spotted Frog (Rana pretiosa) survival and recovery habitat mapping for extant and historical populations and a potential reintroduction site in southwestern British Columbia. LGL Project EA3193. Unpublished report by LGL Limited environmental research associates, Sidney, B.C. for the Fraser Valley Conservancy, Abbostsford, B.C. 94 pp.

Hayes, M.P., J.D. Engler, S. Van Leuven, D.C. Friesz, T. Quinn, and D.J. Pierce. 2001. Overwintering of the Oregon Spotted Frog (Rana pretiosa) at Conboy National Wildlife Refuge, Klickitat County, Washington 2000–2001. Final report to the Washington Department of Transportation. Washington Department of Fish and Wildlife, Olympia, WA. 86 pp. Cited in Pearl and Hayes (2004).

Licht, L.E. 1969. Comparative breeding behavior of the red-legged frog (Rana aurora aurora) and the western spotted frog (Rana pretiosa pretiosa) in southwestern British Columbia. Canadian Journal of Zoology 47: 1287–1299.

Licht, L.E. 1986a. Comparative escape behavior of sympatric Rana aurora and Rana pretiosa. The American Midland Naturalist 115:239–247.

Licht, L.E. 1986b. Food and feeding behavior of sympatric red-legged frogs, Rana aurora, and spotted frogs, Rana pretiosa, in southwestern British Columbia. The Canadian Field-Naturalist 100:22–31.

McAllister, K.R. and W.P. Leonard. 1997. Washington State status report for the Oregon Spotted Frog. Washington Dep. Fish and Wildlife, Seattle, WA. 38 pp.

NatureServe. 2011. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. (Accessed: November 7, 2011).

Pearl, C.A. and M.P. Hayes. 2004. Habitat associations of the Oregon Spotted Frog (Rana pretiosa): a literature review. Final report. Washington Dep. Fish and Wildlife, Olympia, WA.

Pearson, M. M. 2010. Oregon Spotted Frog habitat prioritization in preparation for OSF introduction to new habitats. Unpublished report prepared for the Oregon Spotted Frog Recovery Team, Fraser Valley Conservancy, B.C. Conservation Foundation, and South Coast Conservation Program. 31 pp.

Peterman, W.E., and R.D. Semlitsch. 2008. Impacts of even-aged timber harvest on larval salamanders and the efficacy of riparian buffers in mitigating population declines. Forest Ecology & Management 257:8-14.

Popescu, V.D.  2012.  Habitat selection by Oregon Spotted Frogs (Rana pretiosa) in British Columbia.  Unpublished report prepared for the Canadian Wildlife Service and the Oregon Spotted Frog Recovery Team.  29 pp.

Rashin, E. B., C. J. Clishe, A. T. Loch, and J. M. Bell. 2006. Effectiveness of timber harvest practices for controlling sediment related water quality impacts. Journal of the American Water Resources Association 42 (5):1307-1327.

Vesely, D.G. and W.C. McComb. 2002. Salamander abundance and amphibian species richness in riparian buffer strips in the Oregon Coast Range. Forest Science 48:291–297.

Watson, J.W., K.R. McAllister, and D.J. Pierce. 2003. Home ranges, movements, and habitat selection of Oregon Spotted Frogs (Rana pretiosa). J. Herpetol. 37:292–300.

Personal Communications

Govindarajulu, P. Amphibian Specialist and Oregon Spotted Frog Recovery Team Co-Chair. B.C. Ministry of Environment, Victoria, B.C.

Hayes, M. Senior Research Scientist and Oregon Spotted Frog Expert. Washington Department of Fish and Wildlife, Olympia, Washington, U.S.A.

Pearson, M. M. Environmental Consultant and Oregon Spotted Frog Expert. Balance Ecological, Vancouver, B.C.

Welstead, K.  Species at Risk Biologist and Oregon Spotted Frog Recovery Team Co-Chair.  B.C. Ministry of Forests, Lands, and Natural Resource Operations, Surrey, B.C.

Appendix 1: Maps of Critical Habitat for Oregon Spotted Frog in Canada

Figure A.1. The four areas within which critical habitat occurs for the Oregon Spotted Frog in Canada. Critical habitat is identified at the four extant locations of Oregon Spotted Frog: Mountain Slough, Maria Slough, Morris Valley, and Aldergrove.
Map
Long description for Figure A.1.

Figure A.1. is an overview map of the four areas within which critical habitat is found as well as their associated 10 km x 10 km standardized UTM grid squares. There are two 10 km by 10 km grid squares encompassing the Aldergrove population which is located west of Abbotsford B.C. There are four grid squares encompassing the Morris Valley population located north of Chilliwak B.C. There are two grid squares encompassing the Maria Slough population located northeast of Chilliwak B.C. There is one grid square encompassing the Mountain Slough population located northeast of Chilliwak B.C. The grid squares for Morris Valley, Mountain Slough and Maria Slough are all adjacent to each other.

Figure A.2. Critical habitat for the Oregon Spotted Frog at Mountain Slough (Agassiz, B.C.) is represented by the yellow shaded polygons comprising 940 ha, where the criteria and methodology set out in section 3.1 are met. The 10 km x 10 km UTM grid overlay shown on this figure is a standardized national grid system that indicates the general geographic area containing critical habitat.
Map
Long description for Figure A.2.

Figure A.2. shows the detailed polygon within which critical habitat is found at Mountain Slough (Agassiz, BC) and its associated 10 km x 10 km standardized UTM square.  The detailed polygon within which critical habitat is found, is an irregularly shaped network of lines that occupies the central portion of the 10 km by 10 km grid square.  Immediately to the south of the detailed polygon, the Fraser River can be seen.

Figure A.3. Critical habitat for the Oregon Spotted Frog at Maria Slough (Agassiz, B.C.) is represented by the yellow shaded polygons comprising 906.4 ha, where the criteria and methodology set out in section 3.1 are met. The 10 km x 10 km UTM grid overlay shown on this figure is a standardized national grid system that indicates the general geographic area containing critical habitat.
Map
Long description for Figure A.3.

Figure A.3. shows the detailed polygon within which critical habitat is found at Maria Slough (Agassiz, BC) and the associated 10 km x 10 km standardized UTM squares.  The detailed polygon within which critical habitat is found, is an irregularly shaped network of lines located in the lower half of the more northerly 10 km x 10 km grid square and the top half of the more southerly 10 km x 10 km grid square.  A large river is found to the east of the detailed polygon.

Figure A.4. Critical habitat for the Oregon Spotted Frog at Morris Valley (Fraser Valley Regional District, B.C.) is represented by the yellow shaded polygons comprising 1250 ha, where the criteria and methodology set out in section 3.1 are met. The 10 km x 10 km UTM grid overlay shown on this figure is a standardized national grid system that indicates the general geographic area containing critical habitat
Map
Long description for Figure A.4.

Figure A.4. shows the detailed polygon within which critical habitat is found at Morris Valley (Fraser Valley Regional District, Electoral Area C, BC) and the associated 10 km x 10 km standardized UTM squares.  The detailed polygon within which critical habitat is found, is an irregularly shaped network of lines located primarily in the bottom right and bottom left 10 x 10 km grid squares – of the four grid squares. A waterbody can be seen to the east of the detailed polygon.

Figure A.5. Critical habitat for the Oregon Spotted Frog at Aldergrove (Township of Langley, B.C.) is represented by the yellow shaded polygons comprising 620 ha, where the criteria and methodology set out in section 3.1 are met. The 10 km x 10 km UTM grid overlay shown on this figure is a standardized national grid system that indicates the general geographic area containing critical habitat.
Map
Long description for Figure A.5.

Figure A.5. shows the detailed polygon within which critical habitat is found at Aldergrove (Township of Langley, BC) and the associated 10 km x 10 km standardized UTM squares.  The detailed polygon within which critical habitat is found, is an irregularly shaped network of lines located primarily in the left grid square (of two grid squares).  Through the centre of the map, runs highway 1.  In the lower portion of the map, the border with the United States can be seen.

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