Western painted turtle (Chrysemys picta bellii): COSEWIC assessment and status report 2016

Pacific Coast population - Threatened
Intermountain – Rocky Mountain population - Special Concern
Prairie/Western Boreal – Canadian Shield population - Not at Risk
2016

Table of contents

• Table of contents
• Assessment summary
• Executive summary
• Technical summary: Pacific Coast population
• Technical summary: Intermountain – Rocky Mountain population
• Technical summary: Prairie/Western Boreal – Canadian Shield population
• Preface
• Wildlife species description and significance
  • Name and classification
  • Morphological description
  • Population spatial structure and variability
  • Designatable units
  • Special significance
• Distribution
  • Global range
  • Canadian range
  • Extent of occurrence and area of occupancy
  • Search effort
• Habitat
  • Habitat requirements
  • Habitat trends
• Biology
  • Life cycle and reproduction
  • Physiology and adaptability
  • Diet
  • Dispersal and migration
  • Interspecific interactions
• Population sizes and trends
  • Sampling effort and methods
  • Abundance
  • Fluctuations and trends
  • Rescue effect
• Threats and limiting factors
  • Limiting factors
  • Threats
  • Number of locations
• Protection, status and ranks
  • Legal protection and status
  • Non-Legal status and ranks
  • Habitat protection and ownership
• Acknowledgements and authorities contacted
• Information sources
• Biographical summary of report writers
• Collections examined

List of figures

• Figure 1. Basking Western Painted Turtles, Chrysemys picta bellii, showing their smooth, rounded carapace (upper shell). Photo credit: Evanne Barrett, VAST Resource Solutions.
• Figure 2. Distinctive brightly coloured and reticulated patterning of the plastron (lower shell) of a Western Painted Turtle, Chrysemys picta bellii. Photo credit: Evanne Barrett, VAST Resource Solutions.
• Figure 3. Location (A) and STRUCTURE bar plot (B), averaged over 10 iterations, for Western Painted Turtles at localities sampled by Jensen et al. (2014a) in British Columbia. Genetic clusters identified in B correspond with the coloured star beside the cluster’s name below the bar plot. Note Sunshine Coast (purple) consists of two sites (stars) that are virtually superimposed at this scale. See Figure 4 in Jensen et al. (2014a) for a full explanation of bar plot.
• Figure 4. All reported observations of Western Painted Turtle (Chrysemys picta bellii) in Canada, including whether occurrences are deemed to be extant (naturally occurring) or presumed or suspected to have been introduced. See Table 1 for data sources.
• Figure 5. Global range of Painted Turtle, Chrysemys picta, showing four recognized subspecies: Western Painted Turtle (C.p. bellii) in blue; Midland Painted Turtle (C.p. marginata) in orange; Southern Painted Turtle (C.p. dorsalis) in green; Eastern Painted Turtle (C.p. picta) in red. Areas of intergrade show a blending of these colours where ranges overlap. Source: adapted from Wikimedia Commons (2014). Edited to show region of bellii – marginata intergradation east of Lake Superior; Alberta range to Missouri (Milk) River watershed; British Columbia range better reflects known occurrences.
• Figure 6. Range and occurrence of Western Painted Turtle, Chrysemys picta bellii, in Alberta, Saskatchewan, Manitoba and Ontario. Orange shaded areas follow major watersheds (mapping source: National Hydro Network 2007). Northern range limit in eastern Saskatchewan and Manitoba west of Lake Winnipeg is unknown. See Table 1 for Western Painted Turtle data sources from Alberta (green symbols), Saskatchewan (blue symbols) and Manitoba (orange symbols); Ontario: purple circles from Ontario Reptile and Amphibian Atlas Program; pink circles from S. Hecnar, unpubl. data. Blue squares indicate C.p. marginata – C.p.bellii intergrades (S. Hecnar unpubl. data).
• Figure 7. Estimated minimum abundance at Western Painted Turtle sites in Pacific Coast Population. Small yellow circle: <10 individuals; mid-sized blue circle: 10-100 individuals; large green circle: >100 individuals; red square: extirpated. Note that there is much uncertainty about population sizes, particularly for Vancouver Island north of the Capital Regional District.
• Figure 8. Primary roads in relation to Western Painted Turtle occurrences in British Columbia: A) Pacific Coast population and B) Intermountain – Rocky Mountain population.
• Figure 9. Primary roads in relation to Western Painted Turtle occurrences in the Prairie/Western Boreal – Canadian Shield population.

List of tables

• Table 1. Data sources for Western Painted Turtle, Chrysemys picta bellii, records by population.
• Table 2. Projected regional human population growth over next 26 years (maximum extent of projected estimates) in areas of British Columbia where Western Painted Turtle, Chrysemys picta bellii, occurs, divided by Designatable Unit. Source: BC Stats (2014).
• Table 3. Proportion of the population within regions within the Pacific Coast Population for Western Painted Turtle. Data are from Table 4. Lower and higher limits should be viewed with extreme caution, especially for Vancouver Island and Saltspring Island where few sites have been subjected to mark-recapture studies.
• Table 4. Status of known Western Painted Turtle sites in Pacific Coast Population, by subpopulation (cluster of observations) and region. Modified and updated from Appendix 1/Table 4 in the provincial recovery plan (Western Painted Turtle Recovery Team 2016). Cluster numbers 1 – 37 are as per the above document and include 1 with recovery habitat only (#23) and 1 historical/recovery site (#5), while numbers 38 – 41 represent additional clusters/subpopulations (not in 2016 recovery plan).
• Table 5. Number of Western Painted Turtles (WPT) observed and or estimated from recent field studies in two Designatable Units in British Columbia. Minimum number alive (MNA) values should be viewed with caution because they are based on numbers observed during surveys (single or repeated) at any one time or opportunistically without correction for detectability, or in a few cases on the Lower Mainland or Sunshine Coast on estimates from mark-recapture data.
• Table 6. Summary of Threat scores for each Population / Designatable Unit of Western Painted Turtle. See Table 7 for a summary of Threat Score tallies and Appendices 2 – 4 for the entire threat calculator spreadsheets.
• Table 7. Threats to three populations of Western Painted Turtle, Chrysemys picta bellii, summarized by threat impact.
• Table 8. Conservation Rankings for Western Painted Turtle by NatureServe (2016). Which Painted Turtle taxon is ranked varies by jurisdiction. Species, subspecies, and population ranks are given for Global and National levels. At the Sub-national level, ranks are given to the lowest taxonomic level.

List of appendices

• Appendix 1. Threats assessment for the Western Painted Turtle – Pacific Coast Population.
• Appendix 2. Threats assessment for the Western Painted Turtle – Intermountain - Rocky Mountain Population.
• Appendix 3. Threats assessment for the Western Painted Turtle – Prairie/Western Boreal – Canadian Shield Population.

Document information

COSEWIC status reports are working documents used in assigning the status of wildlife species suspected of being at risk. This report may be cited as follows:

COSEWIC. 2016. COSEWIC assessment and status report on the Western Painted Turtle Chrysemys picta bellii, Pacific Coast population, Intermountain – Rocky Mountain population and Prairie/Western Boreal – Canadian Shield population,in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. xxi + 95 pp. (Species at Risk Public Registry website).

Previous report(s):

COSEWIC 2006. COSEWIC assessment and status report on the Western Painted Turtle Chrysemys picta bellii (Pacific Coast population, Intermountain – Rocky Mountain population and Prairie/Western Boreal – Canadian Shield population) in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. vii + 40 pp.

Production note:

COSEWIC would like to acknowledge Ian Adams and Leigh Anne Isaac for writing the draft of the status report on the Western Painted Turtle (Chrysemys picta bellii) in Canada, prepared under contract with Environment and Climate Change Canada. This report was overseen, edited and updated by Kristiina Ovaska, Co-chair of the COSEWIC Amphibians and Reptiles Specialist Subcommittee.

For additional copies contact:

COSEWIC Secretariat
c/o Canadian Wildlife Service
Environment and Climate Change Canada
Ottawa, ON
K1A 0H3

Tel.: 819-938-4125
Fax: 819-938-3984
E-mail: COSEWIC E-mail
Website: COSEWIC

Également disponible en français sous le titre Ếvaluation et Rapport de situation du COSEPAC sur la Tortue peinte de l'Ouest (Chrysemys picta bellii), population de la côte du Pacifique, population intramontagnarde – des Rocheuses et population des Prairies / Boréal de l’Ouest - Bouclier canadien au Canada.

Cover illustration/photo:

Western Painted Turtle (Chrysemys picta bellii) northeast of Cranbrook, British Columbia; photo courtesy of Ben Meunier.

COSEWIC assessment summary

Assessment summary – November 2016

Common name:

Western Painted Turtle - Pacific Coast population

Scientific name:

Chrysemys picta bellii

Status:

Threatened

Reason for designation:

The distribution of this population overlaps with an area of dense human population in southwestern British Columbia, including the Lower Fraser Valley, where wetland loss has been extensive. Across its range, this population continues to face multiple threats from habitat loss and alteration, road mortality, and introduced species, such as Bullfrog and introduced turtles. Survey efforts within the past 10 years have revealed many new localities, bringing the total number of occupied waterbodies to over 80, grouped within 39 clusters. However, the Canadian population and local subpopulations are small and many, especially in the Lower Fraser Valley, are declining or considered not viable. The long-term persistence of the Canadian population remains precarious.

Occurrence:

British Columbia

Status history:

Designated Endangered in April 2006. Status re-examined and designated Threatened in November 2016.

Common name:

Western Painted Turtle- Intermountain – Rocky Mountain population

Scientific name:

Chrysemys picta bellii

Status:

Special concern

Reason for designation:

This population occurs mainly in larger valleys, which have been subjected to extensive wetland loss and habitat alteration from human activities. The population is suspected to be declining because of continuing loss and fragmentation of habitats and road mortality. The number of turtles is likely small, and the population may become Threatened if threats are neither reversed nor managed with demonstrable effectiveness.

Occurrence:

British Columbia

Status history:

Designated Special Concern in April 2006. Status re-examined and confirmed in November 2016.

Common name:

Western Painted Turtle - Prairie / Western Boreal - Canadian Shield population

Scientific name:

Chrysemys picta bellii

Status:

Not at Risk

Reason for designation:

This population occurs in numerous waterbodies across its wide range. Local declines have undoubtedly occurred from habitat loss, alteration, and fragmentation, and these threats continue. However, there is no evidence of widespread declines or range contraction, and large areas of habitat are still relatively remote and with low threats.

Occurrence:

Alberta, Saskatchewan, Manitoba, Ontario

Status history:

Designated Not at Risk in April 2006. Status re-examined and confirmed in November 2016.

COSEWIC executive summary

Western Painted Turtle
Chrysemys picta bellii

Pacific Coast population
Intermountain – Rocky Mountain population
Prairie/Western Boreal – Canadian Shield population

Wildlife species description and significance

Western Painted Turtles (Chrysemys picta bellii, Gray 1831) are relatively large-bodied painted turtles with adults reaching up to 25 cm in carapace (dorsal shell) length. The subspecies has a distinct bright orange plastron (ventral shell) with a complex pattern of reticulated black lines.

In Canada, Western Painted Turtles occur in three discrete broad areas, corresponding to the following designatable units: Pacific Coast and Intermountain – Rocky Mountain populations in British Columbia, and Prairie/Western Boreal – Canadian Shield population east of the Rocky Mountains. Western Painted turtles in British Columbia show extensive genetic differentiation, sometimes over short distances. This report recognizes these differences but maintains the three designatable units from the previous COSEWIC assessment (2006), based on considerations of discreteness and significance of the variation.

Distribution

The distribution of the Prairie/Western Boreal – Canadian Shield population extends from the Algoma region of northern Ontario, west across the southern prairies to southeastern Alberta. Its natural range in Alberta is limited to the Milk River watershed, but numerous introduced subpopulations exist, some of which have been well established for close to a century or longer. The Intermountain – Rocky Mountain population occurs primarily in major valley bottoms between mountain ranges across the Southern Interior of British Columbia. Major population centres include the Thompson and Okanagan valleys, the southern East Kootenay Trench, and the southern Cariboo Region. The Pacific Coast population occurs in the Lower Fraser Valley from about Chilliwack to Greater Vancouver, Sunshine Coast north to Powell River, Texada Island, and parts of Vancouver Island including the Capital Regional District, Nanaimo area, and Alberni Valley.

Habitat

Western Painted Turtles are highly aquatic and are found in shallow waters of ponds, lakes, oxbows, and marshes, in slow-moving stream reaches, and in quiet backwater sloughs of rivers. Usually, their habitat contains muddy substrates with emergent aquatic vegetation, exposed vegetation root mats, floating logs, and open banks. Painted Turtles prefer floating logs, branches, or other emergent objects for basking. Nesting habitats are on land adjacent to aquatic foraging habitat, usually within 200 m of the water body, typically on gentle south-facing slopes. Eggs are laid in well-drained sites with soil, sand or gravel substrates that have minimal or no plant cover.

Biology

Adult Western Painted Turtles are omnivorous and forage on aquatic vegetation, carrion, and small live prey in shallow waters during the active season from spring to autumn. Younger turtles tend to be more carnivorous and feed on a variety of invertebrates and tadpoles. Eggs hatch in autumn, but hatchlings usually remain in the nest for their first winter. Hatchlings are freeze-tolerant to at least -10°C. Painted Turtles are considered to be one of the most tolerant vertebrates of hypoxic (oxygen-poor) conditions. Predation on eggs and hatchlings can be very high. Age at maturity is thought to range from 4 to 10 years for males and from 6 to 15 years for females. Generation time is estimated to be approximately 25 to 30 years for the Pacific Coast population and 30 to 40 years for the Intermountain – Rocky Mountain and Prairie/Western Boreal – Canadian Shield populations.

Population size and trends

There are no accurate estimates of population size for any of the three populations. The Pacific Coast population probably consists of approximately 3000 or fewer adults. The Intermountain – Rocky Mountain population may have 5,000 – 10,000 adults, while the Prairie/Western Boreal – Canadian Shield population may have 10,000s of adults. None of these estimates are based on robust methods. Inferred from habitat loss, the Pacific Coast population has most likely declined from historical levels by an unknown percentage. The number of known localities has increased greatly over the past ten years due to search efforts. The Intermountain – Rocky Mountain population has also likely suffered declines from historical levels, especially in the Okanagan Valley, based on habitat trends. Population trends for the Prairie/Western Boreal – Canadian Shield population are unknown, but localized declines are likely.

Threats and limiting factors

The main threats to Western Painted Turtles are from habitat loss and alteration, and road mortality. Habitat loss and alteration result from a variety of threats including residential and industrial development, agricultural activities that drain or infill water bodies, and free-ranging cattle that degrade water bodies. Turtles face threats from road mortality during seasonal migrations, when females move from water bodies to terrestrial nesting areas and when both males and females disperse. Other threats include invasive species, such as American Bullfrogs on the coast that prey on hatchlings and plants that reduce the quality of their nesting grounds. Recreational use can disturb basking and nesting turtles. Off-road vehicle use may degrade ponds and adjacent riparian habitats or damage nesting sites. Pollution runoff may affect water quality; sources include agricultural and septic tank runoff and industrial pollutants. Combined, threats for the Pacific Coast population were scored as “Very High”, for the Intermountain – Rocky Mountain population as “High”, and for the Prairie/Western Boreal – Canadian Shield population as “Medium”.

Protection, status, and ranks

Western Painted Turtle was assessed by COSEWIC as three populations in 2006: Pacific Coast - Endangered; Intermountain-Rocky Mountain - Special Concern; and Prairie/Western Boreal – Canadian Shield - Not at Risk. The Pacific Coast and Intermountain – Rocky Mountain populations were placed on Schedule 1 of the Species at Risk Act (SARA) in their respective designations. A provincial recovery plan for the Pacific Coast population was finalized in June 2016. Critical Habitat has been drafted but not yet identified under SARA. There are no specific habitat protection measures in place for Western Painted Turtles. The species does benefit from some municipal planning measures designed to maintain environmentally sensitive areas and certain water bodies. These measures have limited scope and application.

Technical summary: Pacific Coast population

Demographic information

Extent and occupancy information

ⁱ Note: See Definitions and abbreviations on COSEWIC website and IUCN (Feb 2014) for more information on this term.

Number of mature individuals (in each subpopulation)

Quantitative analysis

Threats (actual or imminent, to populations or habitats, from highest impact to least)

Rescue effect (immigration from outside Canada)

ⁱⁱ See Table 3 (Guidelines for modifying status assessment based on rescue effect).

Data-sensitive species

Status history

Status and reasons for designation:

Applicability of criteria:

Technical summary: Intermountain – Rocky Mountain population

Demographic information

Extent and occupancy information

ⁱⁱⁱⁱ See Definitions and abbreviations on COSEWIC website and IUCN (Feb 2014) for more information on this term.

Number of mature individuals (in each subpopulation)

Quantitative analysis

Threats (actual or imminent, to populations or habitats, from highest impact to least)

Rescue effect (immigration from outside Canada)

^iv See Table 3 (Guidelines for modifying status assessment based on rescue effect).

Data-sensitive species

Status history

Status and reasons for designation:

Applicability of criteria:

Technical summary: Prairie/Western Boreal – Canadian Shield population

Demographic information

Extent and occupancy information

^v See Definitions and abbreviations on COSEWIC website and IUCN (Feb 2014) for more information on this term.

Number of mature individuals (in each subpopulation)

Quantitative analysis

Threats (actual or imminent, to populations or habitats, from highest impact to least)

Rescue effect (immigration from outside Canada)

^vi See Table 3 (Guidelines for modifying status assessment based on rescue effect).

Data-sensitive species

Status history

Status and reasons for designation:

Applicability of criteria:

Preface

Advances in knowledge of the Western Painted Turtle since the previous status report (COSEWIC 2006) have been in genetic structure and distribution of British Columbia populations. The entire genome of the Western Painted Turtle is now known (Shaffer et al. 2013), and work in British Columbia has initiated an understanding of the conservation genetics of the subspecies (Jensen 2013; Jensen et al. 2014a). The number of known localities on the southwest coast of British Columbia, especially on Vancouver Island, has increased greatly due to survey efforts over the past 10 years. There remains little knowledge available for the species east of British Columbia, although Western Painted Turtle is now being tracked by the Ontario provincial government as a species of interest.

A provincial recovery strategy for the Pacific Coast population has been posted, including draft Critical Habitat delineation (Western Painted Turtle Recovery Team 2016). An Aboriginal Traditional Knowledge (ATK) source report has been prepared for the Western Painted Turtle (Armstrong 2014). The report lists three potential sources of information for turtles in British Columbia; only one report was available.

COSEWIC history

The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) was created in 1977 as a result of a recommendation at the Federal-Provincial Wildlife Conference held in 1976. It arose from the need for a single, official, scientifically sound, national listing of wildlife species at risk. In 1978, COSEWIC designated its first species and produced its first list of Canadian species at risk. Species designated at meetings of the full committee are added to the list. On June 5, 2003, the Species at Risk Act (SARA) was proclaimed. SARA establishes COSEWIC as an advisory body ensuring that species will continue to be assessed under a rigorous and independent scientific process.

COSEWIC mandate

The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) assesses the national status of wild species, subspecies, varieties, or other designatable units that are considered to be at risk in Canada. Designations are made on native species for the following taxonomic groups: mammals, birds, reptiles, amphibians, fishes, arthropods, molluscs, vascular plants, mosses, and lichens.

COSEWIC membership

COSEWIC comprises members from each provincial and territorial government wildlife agency, four federal entities (Canadian Wildlife Service, Parks Canada Agency, Department of Fisheries and Oceans, and the Federal Biodiversity Information Partnership, chaired by the Canadian Museum of Nature), three non-government science members and the co-chairs of the species specialist subcommittees and the Aboriginal Traditional Knowledge subcommittee. The Committee meets to consider status reports on candidate species.

Definitions (2016)

Wildlife species

A species, subspecies, variety, or geographically or genetically distinct population of animal, plant or other organism, other than a bacterium or virus, that is wild by nature and is either native to Canada or has extended its range into Canada without human intervention and has been present in Canada for at least 50 years.

Extinct (X)

A wildlife species that no longer exists.

Extirpated (XT)

A wildlife species no longer existing in the wild in Canada, but occurring elsewhere.

Endangered (E)

A wildlife species facing imminent extirpation or extinction.

Threatened (T)

A wildlife species likely to become endangered if limiting factors are not reversed.

Special concern (SC)
(Note: Formerly described as “Vulnerable” from 1990 to 1999, or “Rare” prior to 1990.)

A wildlife species that may become a threatened or an endangered species because of a combination of biological characteristics and identified threats.

Not at risk (NAR)
(Note: Formerly described as “Not In Any Category”, or “No Designation Required.”)

A wildlife species that has been evaluated and found to be not at risk of extinction given the current circumstances.

Data deficient (DD)
(Note: Formerly described as “Indeterminate” from 1994 to 1999 or “ISIBD” [insufficient scientific information on which to base a designation] prior to 1994. Definition of the [DD] category revised in 2006.)

A category that applies when the available information is insufficient (a) to resolve a species’ eligibility for assessment or (b) to permit an assessment of the species’ risk of extinction.

Wildlife species description and significance

Name and classification

The Painted Turtle (Chrysemys picta, Schneider 1783) is a member of the marsh and pond turtle family, Emydidae, and is the sole member of the genus Chrysemys (Ernst 1971). In Canada, three subspecies of Painted Turtle are currently recognized: Western Painted Turtle(C. p. bellii, Gray 1831), Midland Painted Turtle (C. p. marginata, Agassiz 1857), and Eastern Painted Turtle(C. p. picta, Schneider 1783). A fourth subspecies, Southern Painted Turtle(C. p. dorsalis, Agassiz 1857), occurs in the southern United States (Ernst and Lovich 2009). Subspecies differentiation is based largely on morphological features such as body size, and shell colour and pattern (Ernst and Lovich 2009). Recent genetic work on Western Painted Turtle suggests it is clearly a distinctive subspecies within the C. picta species complex (Jensen et al. 2015).

Morphological description

The Western Painted Turtle is a medium-sized freshwater turtle and the largest-bodied subspecies of painted turtles with adults reaching approximately 25 cm in carapace length (Matsuda et al. 2006; Ernst and Lovich 2009). Marchand et al. (2015) recently reported the largest documented C. picta individual, a female from Wascana Marsh (Regina, Saskatchewan) with a straight-line carapace length of 266 mm and weight of 2590 g. Painted Turtles have a low, smooth carapace that is darkly coloured (Figure 1). In the different subspecies, the unhinged plastron (ventral shell) varies from solid yellow to orange with reticulated black patterning (Figure 2). The plastron of the Western Painted Turtle is bright orange or reddish, and a dark mark extends along the ventral midline radiating outwards in a complex pattern of reticulated black lines. The head, tail and limbs are dark with yellow stripes. Shell and appendage colour patterns are present through all life stages.

Adult females tend to be larger than males. Males have longer claws on their webbed forefeet, longer and wider tails, and the cloacal opening is positioned closer to the end of the tail than the carapace (upper shell) compared to females (Stebbins 1966).

Population spatial structure and variability

While detailed genetic information is available from British Columbia (Jensen et al. 2014a), no such information is available for the Prairie/Western Boreal – Canadian Shield population. Given the extent of genetic variation among populations in British Columbia, similar differences are probable within the Prairie/Western Boreal – Canadian Shield population but remain unknown.

The physical geography of southern British Columbia presents significant barriers to turtle movement. The Pacific Coast population is isolated from other populations to the east by the Coast and Cascade mountain ranges. This separation is clearly evident for Western Painted Turtles in western Washington State and in British Columbia (Barela and Olson 2014). Similarly, mountain barriers to turtle movement occur between the Okanagan and Columbia river basins (between Intermountain and Rocky Mountain populations) and within the Rocky Mountain population between the Columbia River and lower Kootenay River (Creston Valley, British Columbia and the upper Kootenay watershed) (East Kootenay region).

At the northern limit of the Western Painted Turtle’s distribution in British Columbia, there is a gap in occurrences between the Kamloops / North Thompson River area and the southern Cariboo region (Bonaparte Plateau). Genetic evidence (Jensen et al. 2014a) suggests that Western Painted Turtles in the Cariboo are distinct from other populations, but this is based on sampling turtles (n = 24) from only one lake near Williams Lake.

The northern limit of the Painted Turtles’ range is thought to be influenced by low winter temperature and/or anoxia in water bodies (St. Clair and Gregory 1990). Despite this, introduced populations have persisted well north of their natural range limit (e.g., north of Grande Prairie and in Edmonton, Alberta, Saskatoon, Saskatchewan, and McBride, British Columbia). Thus, current northern limits may be historical and a reflection of Western Painted Turtles’ range expansion following glaciation rather than due to inability of the turtles to survive farther north (Starkey et al. 2003).

Jensen et al. (2014a) sampled 475 individual Western Painted Turtles captured in 25 water bodies across southern British Columbia (mean = 19 turtles per water body, SD = 6.5, range = 6-37 individuals) and genotyped individuals at nine neutral microsatellite loci. They found a significant amount of pair-wise differentiation among water body comparisons (see Table 2 in Jensen et al. 2014a). Six genetic clusters were identified: three along the south coast, the Cariboo region (based on one water body), the Thompson / Okanagan region (including Revelstoke), and the Kootenay region (Figure 3). Genotypic frequencies varied widely among these clusters, with the six clusters explaining most of the variation (based on Analysis of Molecular Variance, AMOVA) relative to either the status quo of two designatable units in British Columbia, or three faunal provinces (Jensen et al. 2014a). Jensen et al. (2014a) sequenced a subset of the above individuals at the mitochondrial DNA (mtDNA) control region and found no deep divisions. The most common haplotype was shared across the British Columbia distribution, with two novel haplotypes recovered not previously detected in the entire North American range. A star-like haplotype network was reconstructed suggesting no regional structuring, but was consistent with the relatively recent colonization history following the last glaciation as suggested by Starkey et al. (2003).

Designatable units

The Western Painted Turtle was previously assessed by COSEWIC with three designatable units (DUs), based on distribution patterns and combinations of five terrestrial amphibian and reptile faunal provinces (COSEWIC 2013): (1) Pacific Coast, (2) Intermountain and Rocky Mountain (combined), and (3) Prairie/Western Boreal and Canadian Shield (combined). This report maintains these three DUs.

Recent genetic evidence (Jensen et al. 2014a) indicates that Western Painted Turtles have a high degree of genetic variation among regions, and it was suggested that six DUs in British Columbia alone may be warranted. Jensen et al.’s (2014a) divisions are based primarily on genotypic frequencies in each population based on microsatellite analyses. Frequency differences are considered less robust to meet the criterion for discreteness between DUs (COSEWIC 2013). There is also limited, if any, evidence to support the required criterion of “significance” (COSEWIC 2013). There is no genetic evidence of unique local adaptations among Western Painted Turtle in Canada beyond the detection of “novel Control Region haplotypes” in British Columbia that have not been identified elsewhere in North America (Jensen et al. 2014a: p. 269).

Within the two British Columbia DUs, there are no significant differences in ecological settings that would warrant further splitting. Jensen et al.’s (2014a) recommendations are based on Western Painted Turtles from a limited number of water bodies (n = 25 of some 500 water bodies). They recognize a Sunshine Coast population based on two ponds that are 5 km apart (within dispersal capabilities of individual turtles). These two populations (Ruby Lake and Klein Lake) are genetically distinct from West Lake (in their putative “Sunshine Coast-Gulf Island-Mid-Vancouver Island’, [SGV] population) that is just 10 km distant, albeit on Nelson Island, across the ~1.5 km wide marine Agamemnon Channel. West Lake turtles, however, are genetically allied to other “SGV” turtles that are far more isolated (broad marine spans, including the Strait of Georgia) on Texada Island and in the Alberni Valley. That turtles in West Lake have retained similar haplotypes despite an unknown length of isolation from Texada and Alberni Valley turtles but are highly differentiated from nearby turtles on the Sechelt Peninsula makes little ecological sense.

Given the long-standing debate on the origins of Western Painted Turtles on the British Columbia coast (e.g., Storer 1937; McTaggart Cowan 1938; Carl 1952 in Engelstoft and Ovaska 2008) and the question of where turtles are ‘native’ and where they are introduced, a conservative approach is to lump all Western Painted Turtles around British Columbia’s south coast into one DU. While further subdivisions may warrant recognition as management units, there is insufficient evidence for further splitting of the DU at this time.

If the Pacific Coast population is not to be split based on the basis of demonstrated genetic variation and evidence of unique haplotypes, then similarly splitting the Intermountain – Rocky Mountain faunal provinces, based on the same genetic evidence, is not warranted. The geography of British Columbia’s interior is not conducive for turtles dispersing between major valleys (e.g., Cariboo to Okanagan to Columbia to Kootenay), so some level of isolation among turtles in these major valleys is expected. However, there is strong ecological similarity across the Intermountain – Rocky Mountain DU distribution, from the Cariboo to the Okanagan to the East Kootenay. Most turtles occur in small lakes or ponds situated in dry, valley bottom ecosystems, typically Interior Douglas-fir, Ponderosa Pine and Bunchgrass biogeoclimatic zones (see Meidinger and Pojar [1991] and BC Ministry of Forests and Range [undated] for descriptions of biogeoclimatic zones).

The Prairie/Western Boreal – Canadian Shield population may warrant division in the future should more data become available. These two ecological zones are distinct from each other. Western Painted Turtle habitat appears to be quite different between the two zones. Western Painted Turtles on the prairies inhabit mostly riverine habitats, including oxbow lakes associated with relatively slow, meandering prairie rivers (MacCullough and Secoy 1983a). On the Canadian Shield, Western Painted Turtles are found in small lakes, wetlands, beaver ponds, and other such lentic habitats, and generally avoid any water bodies with a significant current (Ernst and Lovich 2009), as is typical of the Canadian Shield rivers. However, there is very little detailed information on Western Painted Turtles east of British Columbia, including lack of genetic data and poor understanding of their distribution and abundance. There is also no apparent gap in their distribution / occurrence along the ecological zone boundary in southeast Manitoba (Figure 4). Therefore, they continue to be lumped together as one DU in this report.

Special significance

The Western Painted Turtle is one of only two extant native freshwater turtles occurring west of Ontario. Although it is not of direct economic value in Canada, it may play an important role in the ecosystem functioning (e.g., litter decomposition) of aquatic systems as previously demonstrated for other species of turtles (Lindsey et al. 2013).

In Canada, the Western Painted Turtle occurs at the northern limit of its geographic distribution (Figure 5). Peripheral populations are often known to genetically diverge from core populations due to added selection pressures, enabling them to inhabit environments with harsher conditions (Safriel et al. 1994; Lesica and Allendorf 1995). Peripheral populations may become more adapted to living in transitional environments and play an important role in the expansion of the species’ range (Lesica and Allendorf 1995; Frazier et al. 2006) in response to changing climates (Hickling et al. 2006). The unique haplotypes in British Columbia Western Painted Turtle populations (Jensen et al. 2014a) support the notion that there has been genetic divergence from more centrally located populations and that this divergence may increase the conservation value of these peripheral populations.

Western Painted Turtles possess characteristics such as environmental sex determination, freeze-tolerance (as hatchlings), and an ability to tolerate extremely anoxic conditions, which make them important model organisms for physiological and genetic studies.

Turtles are significant to First Nation peoples, but at the time of this report, three reports were located but only of them (Jamieson et al. 2009) was available. This report states that the Western Painted Turtle occurs on Shuswap Indian Band land, along with basic ecological notes, but contained no other information relevant to status assessment.

Distribution

Global range

At the species level, Chrysemys picta occurs across the middle latitudes of North America from the Pacific coast in British Columbia and Washington, east to the US Atlantic coast and to Canada’s Maritime provinces (Figure 5). The northernmost natural occurrences for Western Painted Turtle are in the Cariboo Region of central British Columbia (Figure 5; see also Ernst and Lovich 2009).

The Western Painted Turtle subspecies intergrades with C. p. marginata in Michigan’s Upper Peninsula and Ontario’s Algoma district (Weller et al. 2010) south through Illinois and eastern Missouri (Figure 5). The Western Painted Turtle’s range is more or less contiguous across the US and southern Canadian prairies but becomes fragmented through the US southwest. Isolated Western Painted Turtle populations occur in New Mexico, southwest Colorado, Utah and Arizona, though many of these are thought to be introduced. One population is known from Chihuahua in northern Mexico (Dengenhardt et al. 1996). In the west, Western Painted Turtle is present through most of Montana, northern Idaho, the Columbia River basin in Washington, and the Willamette Valley of Oregon. Western Painted Turtles also occur in the Puget Sound region of northwestern Washington, a continuation of the Pacific Coast population that occurs in British Columbia.

Canadian range

In Canada, Western Painted Turtles occur in suitable habitat throughout much of the southern portions of the four western provinces and the southern part of northwestern Ontario (Figure 4). Detailed regional distributions are provided for each population in the following sections.

Pacific Coast population

Western Painted Turtles are known from over 80 discrete water bodies. These represent 39 clusters^Footnote1 of occurrences or subpopulations (“population units”) that combine water bodies considered to be within regular and/or reasonable distance for individuals to move among (Western Painted Turtle Recovery Team 2016; Engelstoft and Ovaska unpubl. data 2016). Each cluster consists of 1 to 13 discrete sites or water bodies.

The Pacific Coast population occurs through the Lower Fraser Valley of British Columbia, from approximately Chilliwack to the coast in Greater Vancouver. Other occurrences are on the Sechelt Peninsula / Sunshine Coast and Powell River area northwest of Vancouver, Texada Island, and Vancouver Island. On Vancouver Island, the Western Painted Turtle is found from Sooke through Greater Victoria to the central Saanich Peninsula; several ponds in Nanaimo; one site by Courtenay; several water bodies in the Alberni Valley, and occasional observations between the above areas on the east coast of the island. In the southern Gulf Islands, Western Painted Turtles have been found only on Saltspring Island.

Whether Western Painted Turtles are native to the British Columbia coast has been debated for decades (see COSEWIC 2006 for a discussion). McTaggart Cowan (1938) considered them native, noting that Western Painted Turtles occur on Texada Island, Pender Harbour (n.b. Pender Harbour is a marine inlet and community on the Sechelt Peninsula / Sunshine Coast, not Pender Island in the southern Gulf Islands), and “several small lakes in the Alberni district.” Genetic evidence from various localities in the Pacific Coast population indicates a long postglacial history of Painted Turtles in the region, consistent with them being native to the area (Jensen 2013). However, there is evidence of people moving painted turtles around in both historical (McTaggart Cowan 1936; Carl 1952) and recent times, and without genetic testing it is impossible to know whether particular local occurrences are introduced. Jensen (2013) noted that the occurrences of 1 - 3 turtles per water body may well be the result of translocations.

Intermountain – Rocky Mountain population

The number of discrete water bodies known to support Western Painted Turtles in the Intermountain – Rocky Mountain population is estimated at approximately 200. The number of “population units,” representing connected water bodies, as defined for the Pacific Coast population above, is unknown.

East of the Cascade and Coast mountains, Western Painted Turtles occur primarily in major valley bottoms between mountain ranges. Main occurrences are in the Okanagan Valley, the Thompson River Valley, and the southern Cariboo region, roughly from 70 Mile House to Williams Lake. In the Kootenay / Columbia region, British Columbia, the Western Painted Turtle is known from the southern portions of the West Kootenay region including water bodies near Nelson, Castlegar, Trail, and Salmo. There is no clear ecological explanation for their distribution through the West Kootenays. A significant population inhabits ponds of the Creston Valley wetlands along the Lower Kootenay River (Isaac 2016). In the East Kootenay region, the Western Painted Turtle occurs in numerous water bodies in the Rocky Mountain Trench from the US border at Montana north to the community of Wasa, British Columbia. There are scattered reports through the Columbia River wetlands between Invermere and Donald, including Spillamacheen, Parson (including observed egg-laying events) and Golden. Most reports come from sightings adjacent to the wetlands rather than in the ponds themselves though this may be an artefact of few people accessing the Columbia Wetland ponds. Apparently isolated occurrences include: Revelstoke, Lower Kettle River Valley (including Grand Forks), north end of Kootenay Lake, Invermere, and Fernie.

Ecologically, Western Painted Turtle distribution is best described as suitable ponds and small lakes at low elevations in the drier subzones of Bunchgrass, Ponderosa Pine, and Interior Douglas-fir biogeoclimatic zones (Meidinger and Pojar 1991; BC Ministry of Forests and Range undated). Habitat availability results in the finger-like distribution across the ecologically diverse landscapes of British Columbia’s Southern Interior.

Prairie/Western Boreal – Canadian Shield population

The distribution of Western Painted Turtle across the Prairie/Western Boreal – Canadian Shield population is best described by major southern watersheds draining into lakes Winnipeg, Manitoba, and Winnipegosis, and Lake Superior. Most occurrences are from the Missouri/Mississippi watershed (including the Milk River drainage) and from the Qu’Appelle, Souris, Assiniboine, and Red River watersheds that drain into Hudson Bay, in the southern Prairie Provinces (Figure 6). Occasional records occur beyond these boundaries into the southern portions of the Saskatchewan River watershed (e.g., Swift Current Creek), and in east-central Saskatchewan, but they are generally absent from this watershed. In the Canadian Shield Faunal Province, occurrences are from the Winnipeg, Manitogan, Bloodvein, and English River watersheds that drain into Lake Winnipeg. In the Great Lakes watershed, Western Painted Turtle records are in the Thunder Bay / Lake Nipigon region. They are notably absent from any Canadian Shield watershed draining into Hudson Bay. The easternmost limits of the Western Painted Turtle in Canada are in the Algoma district north of the eastern end of Lake Superior in White River and Michipicoten watersheds. Weller et al. (2010) reported a 130 km gap between Western Painted Turtleand Midland Painted Turtlerecords in the Algoma district of Northern Ontario with intergrades documented mostly from Lake Superior Provincial Park (Figure 6).

Limiting Western Painted Turtle distribution in Alberta to the Missouri (Milk River) watershed is supported by Western Painted Turtle occurrence records from Montana that indicate the species is also absent from the South Saskatchewan watershed in that state (Montana Field Guide 2014). Most other records beyond these watersheds in Alberta (e.g., Moonshine Lake Provincial Park north of Grande Prairie, Rocky Mountain House, Hanna, Crowsnest Pass region, Lethbridge and Waterton Lakes National Park, and others) and Saskatchewan (e.g., Pike Lake) are considered introduced occurrences. Some of these populations may have been established for decades (Pearson 2005; Quinlan pers. comm. 2014; Kendall pers. comm. 2014; Didiuk pers. comm. 2014). For example, turtles at Pike Lake, south of Saskatoon may have been introduced as early as the 1920s when the area was a destination resort (Didiuk pers. comm. 2014). Similarly, Lee’s Lake in the Crowsnest Pass area of southwestern Alberta has supported turtles since at least the 1920s (Pearson 2005). Their origin is suspected to be introduced (Pearson pers. comm. 2014), though considered possibly native by others (Quinlan pers. comm. 2014).

Some Western Painted Turtle occurrences in creeks of the South Saskatchewan watershed may have resulted from natural emigration. Swift Current Creek supports Western Painted Turtles in multiple localities (Figure 6), and these could easily be turtles that naturally colonized oxbows on this river from the adjacent Upper Qu’Appelle and/or Frenchman river drainages. Their northern range limit in Manitoba and eastern Saskatchewan is unclear. Western Painted Turtles may occur north into the Interlake region and north of Riding Mountain National Park. However, the only extant record in these areas is from the Peguis First Nation lands (Figure 6).

Estimating the number of water bodies that support Western Painted Turtles in the Prairie/Western Boreal – Canadian Shield population is difficult due to lack of survey effort. Western Painted Turtles have not been tracked by these provinces (note: Ontario started tracking Western Painted Turtles in 2014), so data are collected opportunistically, and many records are historical. The largely riverine habitats utilized by Western Painted Turtles on the prairies also make identifying discrete water bodies difficult. In northwestern Ontario, Western Painted Turtles could inhabit innumerable remote lakes, wetlands, and beaver ponds.

Extent of occurrence and area of occupancy

The extent of occurrence (EOO) for the Pacific Coast population in Canada is estimated at 19,256 km² based on the minimum convex polygon method. The index of area of occupancy (IAO) is 528 km², based on the 2 x 2 km grid method. New occurrences continue to be found with increased search effort, including filling in distribution gaps on the east coast of Vancouver Island, but the actual IAO is unlikely to be much larger.

The EOO for the Intermountain – Rocky Mountain population in Canada is estimated at 118,454 km² based on minimum convex polygon. The IAO is 1176 km², based on the 2 x 2 km grid method. These data exclude suspected introduced subpopulations at Fernie and McBride, British Columbia. Undocumented occurrences may exist, increasing the actual IAO.

The EOO for the Prairie/Western Boreal – Canadian Shield population in Canada is estimated at 449,944 km² based on the minimum convex polygon method. The IAO is 1336 km², based on the 2 x 2 km grid method. This estimate is based on mapping known observations, including historical records. The actual IAO is probably larger.

Search effort

Western Painted Turtle data were obtained from numerous sources including: unpublished reports for research / monitoring projects (e.g., Engelstoft and Ovaska 2008, 2011, 2013 - 2015; Weller 2009; Ovaska and Engelstoft 2009, 2010, 2012; Hawkes et al. 2013; Isaac 2014; Jensen et al. 2014a; Tesche 2014; Engelstoft and Thorpe 2015), professional biologists, conservation data centres, herpetological atlases, and provincial and federal Canadian agencies including Parks Canada, Canadian Wildlife Service, and Department of National Defence (Table 1). In addition to formal data requests, a questionnaire was developed and distributed to solicit additional input on population abundance, habitat trends, and conservation threats. Nine completed questionnaires were received from respondents ranging from Ontario to coastal British Columbia, and the responses were incorporated into the appropriate sections in the report.

^a “Recorded” indicates whether the data reported “Individuals” (report of an individual, or multiple turtle sighting at a single location) or “Water body” (report of a pond, lake, wetland or river known to support a Western Painted Turtle population of indeterminate size).

^b A. Dzilums pers. comm. 2014.; L. Halverson pers. comm. 2014.; M. Machmer pers. comm. 2014.; P. Ohanjanian pers. comm. 2014.; L-A. Walker pers. comm. 2014.

Habitat

Habitat requirements

Western Painted Turtles are highly aquatic and are found in shallow waters of ponds, lakes, oxbows and marshes, in slow-moving stream reaches, and quiet backwater sloughs of rivers. Optimal Western Painted Turtle habitat contains muddy substrates with emergent aquatic vegetation, exposed Cattail (Typha sp.) mats, floating logs, and open banks (Matsuda et al. 2006). Painted Turtles prefer floating logs, branches, or other emergent objects that lie offshore or over deeper water for basking (Nussbaum et al. 1983; Macartney and Gregory 1985).

The majority of seasonal activities, such as feeding, basking, mating, and other activities, are generally carried out in the water (Matsuda et al. 2006). Time spent on land is minimal and restricted to brief excursions during the summer nesting season and occasional terrestrial dispersal movements between water bodies, particularly if ponds dry up (McAuliffe 1978).

For nesting, females select exposed patches of soil, sand, or gravel often at the margins of fields, pastures, beaches, or roadsides where digging is possible (Nussbaum et al. 1983; Matsuda et al. 2006). Nest site soils have good drainage, loose surface layers, fairly compact subsurface layers, and are composed of a mixture of small to medium size gravels, fine silts, and sands with low organic content (Macartney and Gregory 1985). Gentle slopes, warm southern exposures, and reduced shrub overstorey are necessary (Schwarzkopf and Brooks 1987; Refsnider et al. 2013). Most nests are within 200 m of their water body with rare records up to 600 m (Ernst and Lovich 2009).

Water features used by Western Painted Turtles appear to be somewhat different in the Prairie portion of the Prairie/Western Boreal faunal province. While elsewhere turtles are primarily found in generally small water bodies with minimal flow, such as ponds, small lakes, or sloughs (St. Clair and Gregory 1990; Basaraba 2014; Isaac 2014; Tesche 2014), on the Prairies, Western Painted Turtles primarily use either riverine habitats or oxbow lakes associated with rivers (MacCulloch and Secoy 1983b; Watkins pers. comm. 2014). Very few, if any, records are from natural prairie wetlands. The extensive research library of the Institute for Wetland and Waterfowl Research focusing on prairie wetlands has no record of turtles (Glass pers. comm. 2014). This suggests they are at least not common in typical prairie pothole wetlands. Many of these wetland ponds are susceptible to drying in the summer months and/or freezing solid in the winter. Either situation would be lethal to Western Painted Turtles. Many larger lakes that are not ephemeral have high salt loads that would also be intolerable to turtles.

Prairie rivers are often described as slow, meandering and “sluggish” (MacCullough and Secoy 1983a), ideal conditions for Painted Turtles who tend to avoid water bodies with strong currents (Ernst and Lovich 2009). Water is deep enough to avoid drying out or freezing but with enough current to keep saline levels low and provide sufficient resources for turtles.

Habitat trends

Pacific Coast population

Continuing urban and agricultural land development, particularly in the Lower Fraser Valley and southern Vancouver Island, is likely to reduce habitat quantity and quality for Western Painted Turtles. Suitable habitat often occurs in isolated patches within human modified landscapes. Human population projections indicate significant growth over the next 10- and 26-year periods (maximum extent of demographic projections; Table 2) in the British Columbia’s south coast region where Western Painted Turtle occurs. Additional human population density is likely to increase development pressure, road building, and traffic on roads, posing habitat isolation and movement problems for Western Painted Turtles.

In the Lower Fraser Basin, only about 1% of the original wetlands remained in 1990 (compared to pre-settlement in1820s), while urban and agricultural lands had increased to cover 26% of the basin landscape by 1990 (Boyle et al. 1997). In the Fraser River Delta, about 70% of the original wetlands have been altered by diking and drainage schemes (Habitat Group 1978). This includes virtually all of the seasonal wet meadows and 84.6% of the bog habitat (Butler and Campbell 1987). Sumas Lake wetlands (formerly one of North America’s most productive wetlands) were drained for agricultural uses in the 1920s (Environment Canada 1992). After World War II, over 2,800 hectares were diked and drained between Pitt Lake and Pitt River, creating the Pitt Polder, a lowland area converted to agriculture by diking and draining. Portions of Cheam Lake, Pitt Polder, and Hatzic Lake were also drained.

Since 1990, wetland losses have continued. Between 1989 and 1999 one in five wetlands in the Fraser Lowlands were lost to agricultural and urban encroachment with a quarter of the remaining wetlands experiencing a further 5 to 15% loss in area (Moore et al. 2003). Between 1989 and 2009, 1352 ha of the original 29,448 ha (4.6%) were lost (Major et al. 2009). How many of these wetlands may have supported Western Painted Turtles is unknown. Primary sources of natural wetland loss were identified as: agriculture (primarily cranberry and other berry production 43%), golf courses (18%), housing development (15%), and landfill (11%). Combined, these account for 87% of observed wetland loss (Major et al. 2009).

On Vancouver Island, Western Painted Turtle habitat has been impacted especially in the Greater Victoria area and along the east coast. Approximately 70% of the original wetlands have been lost in the “Victoria region” (presumably referring to Greater Victoria) (Wetland Stewardship Partnership 2010). On the east side of Vancouver Island and the Gulf Islands, only 1.7% of the land base remains as natural wetlands in 1992 (original coverage not given), and there was a 2% wetland loss during from 1992 – 2002, based on air-photo interpretation (Wetland Stewardship Partnership 2010).

Urban development and extensive road networks have fragmented suitable habitat, and habitat conditions have been further degraded by exotic species introductions (Ovaska and Engelstoft 2012). In the Alberni Valley, habitats are within active forestry lands. Wetlands, especially shallow water pond types preferred by Western Painted Turtle, are not abundant on southeastern Vancouver Island (Ward et al. 1998), and on Vancouver Island the Western Painted Turtle has been found in only 33 (13%) of 245 water bodies surveyed from 2008 to May 2016 (Engelstoft and Ovaska 2008, 2011, 2013 – 2015; Ovaska and Engelstoft 2009, 2010, 2012; Engelstoft and Thorpe 2015; Engelstoft unpubl. data 2016), indicating patchy distribution. In contrast, the introduced Red-eared Slider (Trachemys scripta) was found in 54 (22%) of the water bodies, suggesting that at least some of the unoccupied water bodies provided habitat suitable for turtles. Estimates of historical wetland loss on southern Vancouver Island were not available (McPhee et al. 2000).

Approximately 65% of individuals in the entire Pacific Coast population may be on the Sunshine Coast and Texada Island (Figure 7), so habitat trends and threats are especially meaningful there, but no information was found on recent or historical wetland trends. Wetland loss can be inferred from residential development along coastal regions between Gibsons and Powell River, which has increased over the past decade. Looking forward, further development pressure is expected in this area, as projected human population growth rates are not much lower than in the Lower Fraser Valley (Table 2). A further 12.8% increase in population growth is predicted for the next 10-year period. Development (housing, roads) in this area is concentrated in the same narrow, relatively flat coastal plain where suitable Painted Turtle habitat exists. Forestry also continues to modify habitats, especially in low elevations along the coast (Sunshine Coast Regional District 2003).

Intermountain – Rocky Mountain population

Overall, Western Painted Turtle habitat is considered abundant in localized areas within the range of this population. Questionnaire respondents considered Western Painted Turtle habitat trends to vary considerably among regions. Some areas (e.g., Nisconlith Lake) may experience an increase in habitat due to changes to water flows that are providing more water to kettle lakes and other turtle habitat in the area (Ballin pers. comm. 2014). In the Cariboo region of central British Columbia, increased road densities including highway twinning and greater traffic volumes have increased road mortality. This trend is expected to continue (Steciw pers. comm. 2014).

In the ecologically critical South Okanagan area 85% of the natural wetlands have now been lost to stream channelization, agricultural drainage, and housing (Sarrell 1990). Historical ecosystem mapping completed for the Okanagan Valley by Lea (2008) found that greater than 90% of some wetland ecological community types have been lost. The Okanagan region experienced large declines of 85% and over 90% of some wetland ecological community types between 1800 and 2003 (Sarrell 1990; Lea 2008). More recent rates of wetland loss are unknown, but pressure from human activities continues. Elsewhere (Kootenay and Cariboo regions), wetlands have been drained for agricultural purposes or their functioning reduced by cattle. Dams on the Columbia, Kootenay and Duncan rivers have inundated thousands of hectares of valley-bottom lands, including wetlands, where turtles are most numerous.

Sources of wetland loss and degradation include agricultural activities such as orchards, vineyards, cultivation agriculture, and water body trampling by grazing livestock (see Threats and Limiting Factors). Impacts on turtles result from direct infilling of wetlands and altering of groundwater regimes that recharge many of the lakes, ponds, and wetlands within British Columbia’s Southern Interior (Iverson et al. 2008). There is also increasing pressure from linear developments that increase road mortality especially for nesting females and dispersing turtles. Ongoing urban development, both housing and industrial, may affect turtle habitat, notwithstanding increased habitat protection from development under municipal bylaws designed to maintain sensitive environmental values and watercourses (see Habitat Protection and Ownership).

Where Western Painted Turtle are most vulnerable in the region – the Okanagan Valley – human population growth and increased agricultural water demand under most predicted climate change scenarios are expected to increase local water use by 5% to 40% or more under worst-case scenarios (Polar Geoscience 2012). Human population growth is projected to be greatest in the Okanagan (Table 2), especially the central region, including Kelowna. The more rural Kootenays and Cariboo regions are projected to have much lower human population growth. Increased human population increases development pressures on natural areas and likely increases road and traffic densities that threaten turtles.

Prairie/Western Boreal – Canadian Shield population

Historical trends of Western Painted Turtle habitat in the Prairie/Western Boreal – Canadian Shield population are uncertain. Wetland habitats are known to have declined from historical levels (Watmough and Schmoll 2007), and declines are likely to continue. Western Painted Turtles utilize more riverine habitats on the prairies, not pothole wetlands, so they may not be exposed to as much habitat loss. The extent to which riverine and oxbow habitats have declined over both short and long term is unknown.

Habitat trends in the Prairie ecosystems are likely to range from relatively stable to decreasing over the next ten years. Threats to turtle habitat are from activities that impact water levels, both surface waters in rivers and oxbow sloughs and groundwater reserves that may help recharge surface water areas. The drainages in which Western Painted Turtles occur on the prairies are not fed by glacier melt in the Rocky Mountains (Schindler and Donahue 2006) but are reliant on snow melt and rainfall. Any changes in precipitation levels may, therefore, directly impact water levels and Painted Turtle habitat. The Prairie Pothole Region (where Western Painted Turtle occur but do not necessarily utilize pothole wetlands) has experienced drying conditions throughout the 20th century (Werner et al. 2013), and water scarcity is anticipated to be a major challenge in the region (Sauchyn and Kulshreshtha 2008). Most work has examined pothole wetlands and glacier-fed rivers (e.g., North and South Saskatchewan River watersheds; Schindler and Donahue 2006; Werner et al. 2013), but general drying conditions can be expected to impact the waters inhabited by Western Painted Turtle as well. This compounds already high surface water use (e.g., domestic use, irrigation) within much of the Prairie distribution of Western Painted Turtle in Canada (Environment Canada 2012). The extent to which petroleum exploration and development will impact turtle habitat is uncertain. The largest habitat impact of this activity is likely the associated increase in road network and elevated threat from road mortality.

Habitat trends in northwestern Ontario are likely to be stable overall, but Western Painted Turtle subpopulations there appear to be small and unevenly distributed, increasing their vulnerability to any losses of habitat. Some potential threats to Western Painted Turtle habitat exist in localized mining exploration and development and where forestry practices impinge on inhabited water bodies either by harvest or roads.

Biology

Life cycle and reproduction

Western Painted Turtles exhibit a fairly typical pond turtle life history. In early spring as the water warms, courtship and mating begins and takes place in shallow waters (Ernst and Lovich 2009). Mating has been documented to occur also in the autumn (Pearce and Avise 2001). The majority of females mate prior to each nesting period; however, they also have the ability to store viable sperm for up to 4 years (Pearce and Avise 2001).

Females begin nesting in late May-June and search for well-drained soil or sandy substrates often along roadways, fields, and beaches that face south to southwest (Schwarzkopf and Brooks 1987; COSEWIC 2006). Once a suitable site is located, females dig a 4-14 cm deep, flask-shaped nest and lay ~12 eggs in the late afternoon to early evening (Pearse and Avise 2001; COSEWIC 2006). Females provide no maternal care once the eggs are laid and the nest is covered.

Eggs incubate in the nest for approximately 76 days and hatch in late summer or fall of the same season (COSEWIC 2006). The sex of many freshwater turtles, including Western Painted Turtle, is determined by incubation temperature (Bull 1980). In Canada, newly hatched turtles typically overwinter in the nest and emerge the following spring (Packard et al. 2002; Costanzo et al. 2004). These northern neonates can remain in their natal nest because they are freeze-tolerant and can survive temperatures below -10 ˚C (Packard et al. 2002).

Adult and juvenile Western Painted Turtles spend the warm summer months basking and foraging and move to suitable overwintering habitats in the fall when air and water temperatures decrease. Outside the courtship and mating period, male and female Painted Turtlesgenerally avoid each other (Munoz 2004). Painted turtles hibernate in shallow water below the freezing limit. During winter, turtles can make small movements but become dormant in muddy substrates when conditions become anoxic (Taylor and Nol 1989).

Sexual maturity of painted turtles is thought to be more a function of size than age (Ernst and Lovich 2009) and so may differ regionally. Citing several sources, Ernst and Lovich (2009) suggested male Western Painted Turtles mature at a plastron length of 7.0 to 9.5 cm, “usually in years 2-4, but possibly as late as the sixth year in some northern populations.” Females mature at a larger size, with a plastron length of 9.7 to 12.8 cm and up to 17.7 cm in some populations, typically at 6-10 years of age (Ernst and Lovich 2009).

There is very limited survivorship and age of maturity data available for Western Painted Turtles. Studying Midland Painted Turtles in central Ontario, Samson (2003) estimated sexual maturity at 7-10 years for males (n = 15, mean = 8.3, SD = 0.93) and 12-15 years for females (n = 32, mean = 14.1, SD not available). Samson found the annual adult mortality rate was very low at 0.03. Lifespan for Painted Turtles is considered to be between at least 30 and 40 years (Congdon et al. 2003; Ernst and Lovich 2009) and up to 60 years (supporting information in Midwood et al. 2015). Given the large climatic differences across the Western Painted Turtle’s range in Canada, from the temperate west coast to the continental climate of the Prairies and northwestern Ontario, generation time may vary significantly among the three designatable units. It is likely shortest for the Pacific Coast population, estimated to be between 25 to 30 years, while the Intermountain – Rocky Mountain and Prairie/Western Boreal – Canadian Shield populations probably have generation times from 30 to 40 years. The latter two estimates are consistent with those for Midland and Eastern painted turtles (Moldowan pers. comm. 2015).

Physiology and adaptability

Basking is a commonly observed behaviour in a variety of freshwater turtle species. It serves the primary purpose of rapidly raising the body temperature in ectothermic turtles (Boyer 1965; Ernst 1972; Lefevre and Brooks 1995) and has several benefits. Basking facilitates increased metabolic and digestive rates (Avery et al. 1993; Hammond et al. 1988), helps eliminate ectoparasites (Ryan and Lambert 2005), and accelerates egg development in females (Carrière et al. 2008). In addition, basking may be an integral component of skin and shell maintenance by synthesizing vitamin D3 (Acierno et al. 2006) and aiding in the periodic shedding of carapacial scutes (Boyer 1965).

During winter, Western Painted Turtles become dormant and hibernate on the muddy substrates of ponds, lakes, or other types of slow-moving aquatic environments. While dormant, their need for oxygen is greatly decreased (Ultsch et al. 1999), and they may absorb oxygen from the water through their skin, throat linings and thin-walled sacs in the cloaca. It appears, however, that Painted Turtles are unable to maintain aerobic metabolism throughout an extended hibernation. Instead, they survive on anaerobic respiration, by using calcium and magnesium carbonates taken from their shell to buffer lactate accumulation in their tissues (Jackson 2000). This extreme tolerance of anaerobic conditions has been associated with regulatory changes in broadly conserved vertebrate genes, suggesting a genetic basis (Shaffer et al. 2013).

Conversely, some neonates overwinter terrestrially within the natal nest chamber (Ultsch 1989). Because hatchlings usually do not emerge from the nest chamber until the following spring, they may be exposed to temperatures as low as -10°C during hibernation. Winter survival is promoted by freeze-tolerance and supercooling abilities, depending on body temperatures. Hatchlings freeze when body temperatures remain above -4°C (Storey et al. 1988; Churchill and Storey 1992; Costanzo et al. 1995) whereas they use supercooling when body temperatures drop below this level (Packard et al. 1997).

Diet

Small juvenile Painted Turtles feed primarily on tadpoles and aquatic invertebrates such as insects, crayfish and snails. Turtles include bigger prey items in their diets such as frogs and fish as they grow in size (Marchand 1942; Matsuda et al. 2006). As turtles mature and their growth rate declines, individuals become increasingly omnivorous, feeding on live animals and carrion as well as the abundant wetland plant life (Raney and Lachner 1942; Matsuda et al. 2006). Northern populations have been shown to exhibit a greater degree of carnivory (MacCollough and Secoy 1983a; Lindeman 1996).

Dispersal and migration

Overland movements of several hundred metres are not uncommon (House et al. 2010), as individuals presumably attempt to increase the frequency of encounters with potential mates (Thomas and Parker 2000), gain access to resources not available in a previous aquatic habitat (Stone 2001), or escape dramatic declines in quality of habitat (Roe and Georges 2008). Some turtles use different wintering and breeding ponds, and must travel between the two in spring and fall (Ernst and Lovich 2009). Long-distance migrations and dispersal are equally possible in the drier parts of this species’ range in Canada, and turtles must make movements overland from one water body to another or linearly along streams (MacCulloch and Secoy 1983b). Along rivers or where there is aquatic connectivity among water bodies, turtles can readily move up and down along these waterways (Ernst and Lovich 2009). Males in the riverine Saskatchewan habitats moved 21 to 26 km and females less than half that distance, 7 to 8 km (MacCullough and Secoy 1983a). Turtles in ponds and wetlands likely move significantly shorter distances (Ernst and Lovich 2009).

Interspecific interactions

The egg stage is a vulnerable phase of the turtle’s life cycle. Nest predators learn to find nests next to water bodies and can easily dig up the shallow clutch of eggs (Spackman and Hughes 1995). Consequently, depredation on Western Painted Turtle eggs is often very high (Macartney and Gregory 1985; Clark and Grueing 2002). Predators of Painted Turtle eggs include Raccoon (Procyon lotor), Coyote (Canis latrans), skunks (Mephites spp.), mustelids, Black Bear (Ursus americanus), sciurids, corvids, as well as domestic cats (Felis catus)and dogs (Canis familiaris) (see Maltby 2000; Clark and Gruenig 2002; Marchand and Litvaitis 2004; Ernst and Lovich 2009).

Red-eared Sliders are known to occur throughout much of Western Painted Turtle range and may compete with them for basking or nesting sites. While Sliders have been frequently observed to dig nests, there is little evidence of successful hatching under natural conditions. However, live young have been dug out from a nest in southwestern British Columbia recently (Welstead pers. comm. 2015a), suggesting that they at least occasionally survive the winter in the mild climates along the coast. Genetic material from introduced Eastern Painted Turtles has been demonstrated to occur in Western Painted Turtles at Burnaby Lake in the Pacific Coast population (Jensen et al. 2014b), indicating probable interbreeding with released non-native subspecies.

Population sizes and trends

Sampling effort and methods

A population estimate for the Pacific Coast population was provided by a working group based primarily on expert opinion. Minimum number alive data are presented where available; however, away from the Lower Fraser Valley, which has been surveyed intensively, these are typically the number of individuals captured or sighted at any one time during surveys aimed at delineating the distribution of the species or other field projects for which local population estimation was not an objective (e.g., Engelstoft and Ovaska 2011, 2013, 2014, 2015; Jensen 2013).

Abundance

Painted turtle populations (across all subspecies) are highly variable in size, capable of reaching very high densities or subsisting at low numbers (Ernst and Lovich 2009; Eskew et al. 2010). Density of turtles varies widely among water bodies (Ballin unpubl. data 2014; Tesche 2014). Riverine populations (which occur in the Prairie provinces) tend to occur at lower densities because of the ease of dispersal and movement up and down these waterways (Ernst and Lovich 2009). Thus, extrapolating a regional population estimate from an estimate of mean number of turtles per water body is not possible.

No reliable abundance estimates are available for any Western Painted Turtle population in Canada. Visual counts at any water body generally do not produce reliable estimates. They are confounded by an inability to distinguish between adults and juveniles (Ernst and Lovich 2009) and widely variable ability to observe turtles above water at any one time. In order to accurately determine age class, turtles must be closely examined in hand. Because most abundance estimates are based on visual counts from a distance, total counts generally lump adults and juveniles. Age ratios vary widely from site to site (Basaraba 2014; Tesche 2014), so there is no overall ratio that can reliably be applied across sites.

Pacific Coast population

There are no robust population estimates for this population, as surveys outside the Lower Fraser Valley have focused mainly on documenting distribution patterns. However, it is unlikely that the population is much greater than 3000 adults based on the low numbers observed during surveys at most sites and the number of occupied water bodies (tables 3 and 4). Population sizes for many sites on Vancouver Island, in particular, are unknown, as surveys have focused on clarifying distribution, and mark-recapture has been conducted at only a few sites. Approximately 35 - 43% of the population occurs on the Sunshine Coast and Texada Island. Approximately 30% - 43% of the population occurs in the Lower Mainland / Fraser Valley. Southern Vancouver Island (Capital Regional District) may support approximately 10 - 11% and the Alberni Valley / Nanaimo / Gulf Island components approximately 12 – 16% of the population (Table 3). New occurrences continue to be found with increased search effort, especially on Vancouver Island north of the Capital Regional District, and the percentage of the population on the island may be greater than indicated above.

^c Several sites were visited only once in the Alberni Valley and Capital Regional District, Vancouver Island, to clarify distribution. For Lower limit, no correction was applied for detectability; for Higher limit, small wetlands indicated as “unknown” in Table 4 were assumed to contain 10 or 20 adults and large wetlands 50 adults for the purpose of this table.

At least 24 sites are known to have Western Painted Turtles throughout the Lower Fraser River Valley, from Chilliwack to the coast at Alaksen National Wildlife Area. Many of these sites, however, do not have self-sustaining populations. In many instances only one or two turtles are known, suggesting these animals were either introduced or the populations have declined to critically low levels. Given the lengthy lifespan of painted turtles (30 to 40 years, Ernst and Lovich 2009), a population of one or two turtles may persist for decades without any recruitment.

Each of the 39 clusters of extant sites can be considered a subpopulation (see Table 4 for a detailed breakdown). While most subpopulations are small, consisting of less than 10 or 100 adults, a few are presumed to be larger with population size up to 400 (Western Painted Turtle Recovery Team 2016). The largest subpopulations are Garden Bay – Ruby Lake on the Sunshine Coast with estimated 355 – 605 adults, Nicomen Slough in the Lower Fraser Valley with 300 – 350 adults, and Nelson Island with 100 – 400 adults. The size of many of subpopulations, especially in the Alberni Valley on Vancouver Island, is unknown.

Table 4. Status of known Western Painted Turtle sites in the Pacific Coast population, by subpopulation (cluster of observations) and region. Modified and updated from Appendix 1/Table 4 in the provincial recovery plan (Western Painted Turtle Recovery Team 2016). Cluster numbers 1 – 37 are as per the above document and include 1 with recovery habitat only (#23) and 1 historical/recovery site (#5), while numbers 38 – 41 represent additional clusters/subpopulations (not in 2016 recovery plan).

Augmented: head-started juveniles have been released or adults translocated to an area with poor population viability.

Reintroduction: translocation of adults or release of head-started juveniles at a historical site.

“# of adults” is based on the minimum number of turtles alive observed per site without correction for detectability. A few cases sites on the Lower Mainland and Sunshine Coast are based on estimates from mark-recapture data.

^d new observations not in provincial recovery strategy (source: Evelyn pers. comm. 2016)

^e new observations not in provincial recovery strategy (source: C. Engelstoft and K. Ovaska unpubl. data 2016)

Intermountain – Rocky Mountain population

No reliable population estimate is available for the Intermountain – Rocky Mountain population. Numerous site-specific projects provide estimates of minimum number alive and bounded population estimates are available from some field studies in (Table 5). As above, few studies differentiate between adult and subadult turtles. Thus the estimates shown should be assumed to include both, except where noted. Based on extrapolation of these limited site-specific abundance estimates, there may be upwards of 5000 mature adults in the population, possibly less than 10,000, but these are very rough estimates.

^f MNA = Minimum Number Alive

^g Sum of Chapman modified Petersen mark-recapture population estimates across 13 ponds.

Prairie/Western Boreal – Canadian Shield population

Similarly, no population-wide abundance estimate is available for the Prairie/Western Boreal – Canadian Shield population. Given the number of water bodies that are known to support Western Painted Turtles in the Canadian Shield faunal province and high probability of many other water bodies without records supporting turtles, the overall population estimate is probably over 10,000 adult turtles in the Canadian Shield faunal province alone. The situation on the Prairies is less certain. Turtle range narrows north to south toward the west, with native range limited to the Missouri watershed in southeastern Alberta (Figure 6). Abundance likely dwindles toward the western limits of the population because of reduced range and limited amount of suitable habitat, compared to the water-rich Canadian Shield.

Fluctuations and trends

With very limited present population estimates and virtually no historical information beyond a few occurrence records, there is no information available on population trends. A long-term population decline can be inferred from habitat loss in some areas, including much of the Pacific Coast population, especially the Lower Mainland and southern Vancouver Island areas where human population growth and development have been greatest (see Habitat Trends for rates of wetland loss). Precipitous losses of wetland habitat have occurred in the Lower Fraser Valley and Capital Regional District over the past 75 – 90 years (corresponding to 3 generations of the turtles). These two areas make up almost 50% of the range of the Pacific Coast population. While the rate of wetland loss within the remainder of the range is largely unknown, losses have almost certainly occurred. It can be inferred that there has been a habitat loss of at least 35% (70% of the habitat of approximately half the population) over the past three generations.

Looking forward, human population growth is projected to be from 14% over 10 years to 30% over 26 years in the Sunshine Coast where 65% of the Pacific Coast population occurs, with similar figures across most of the DU (Table 2).

A similar situation exists in the Intermountain – Rocky Mountain population where historical habitat loss has occurred through much of the Okanagan Valley and where human development is projected to continue to increase (Table 2). In the East Kootenays, the lack of Western Painted Turtle sightings from the Columbia River wetlands between Invermere and Golden is surprising. They were possibly more widespread throughout this area historically (Larsen pers. comm. 2015), but currently are known from only three localities in a wetland complex stretching over 140 km in length. Similarly Western Painted Turtles were frequently observed along the Eagle River between Revelstoke and Sicamous, British Columbia in the 1970s (Larsen pers. comm. 2015); however, there are no recent records from this area. The interpretation is complicated by lack of systematic surveys over much of the distribution of this DU.

No overall population trend data can be inferred for the Prairie/Western Boreal – Canadian Shield population.

Rescue effect

The ability for natural recolonization of Western Painted Turtle in Canada is primarily limited by the species’ natural dispersal limitations (see Dispersal and Migration). If a population of turtles was to become extirpated, natural recolonization from adjacent United States populations would likely take generations.

Pacific Coast population

The Western Painted Turtle occurs west of the Coast / Cascade Mountains in the Puget Sound region of Washington State and Oregon’s Willamette Valley (Barela and Olson 2014), so extant populations do exist to potentially assist with rescue for the Pacific Coast population. However, the capacity of the species to naturally recolonize is doubtful. The habitat on the Lower Mainland of British Columbia is highly fragmented hindering or preventing movements from the United States. On Vancouver Island and other smaller surrounding islands, there is no possibility of rescue, as they are surrounded by salt water that freshwater turtles cannot cross. Recolonization of extirpated populations would, therefore, have to be through human intervention and reintroduction. The highly variable genetic profiles of Western Painted Turtles on the British Columbia coast (Jensen et al. 2014a) complicate any proposed reintroduction.

Intermountain – Rocky Mountain population

Western Painted Turtle populations in the interior of British Columbia appear to be generally contiguous with adjoining areas in the United States (Barela and Olson 2014). Movement and rescue would be along the generally north-south valley bottoms inhabited by the turtles (e.g., south Okanagan, East Kootenay Trench). Long-distance east-west movements within this population are unlikely to occur given the rugged mountain ranges that lie between each valley bottom. Natural recolonization from the United States is possible, but would be very slow, over the course of numerous generations.

Prairie/Western Boreal – Canadian Shield population

Western Painted Turtle populations across the Prairies are contiguous with those in the United States. The Missouri, Souris and Red River watersheds are all transboundary, facilitating cross-border movements within these waterways. No significant barriers exist between these watersheds and the more northern Qu’Appelle and Assiniboine drainages, in which the vast majority of Western Painted Turtles occur in Saskatchewan and Manitoba. Farther east into northwestern Ontario, Lake Superior and the more rugged Canadian Shield landscape reduce the likelihood of natural recolonization. Western Painted Turtles are thought to have moved into the Algoma district east of Lake Superior from Michigan’s upper peninsula (Weller et al. 2010), where they have intergraded with Midland Painted Turtles.

Threats and limiting factors

Limiting factors

Western Painted Turtles are thought to be limited in their northern distribution by either low winter temperatures and/or severe winter hypoxia (St. Clair and Gregory 1990). However, persistence and evidence of breeding of Western Painted Turtles in Moonshine Lake Provincial Park north of Peace River, Alberta (Kirtley-Wark pers. comm. 2014; Figure 4) since at least the mid-1990s suggests that Western Painted Turtles’ cold tolerance is greater than previously thought. Distribution may be more limited by dispersal capability to colonize novel watersheds.

The “slow” life history, which includes late maturity, small clutch size, and longevity, limits the potential of local populations to recover after a disturbance. Because turtles may live for decades, the presence of turtles in a pond, even for many years, may not represent a viable population.

Threats

Western Painted Turtles face a wide variety of threats across their range in Canada. Broadly categorized, the main threats are habitat loss/alteration from anthropogenic sources and road mortality, as supported by questionnaire respondents, across all populations. Habitat loss and alteration accrue from a variety of sources including residential and industrial development; agricultural activities that drain or infill water bodies; ranging cattle that degrade water bodies; invasive non-native plants, both terrestrial and aquatic, that degrade nesting habitat and water bodies, respectively, and non-native turtles that may outcompete Western Painted Turtles (Red-eared Slider) or hybridize with them (other Painted Turtle subspecies).

Overall threat impact scores are Very High - High for the Pacific Coast population, High - Medium for the Intermountain – Rocky Mountain population, and Medium for the Prairie/Western Boreal – Canadian Shield population (Table 6; see Appendices 1 – 3 for threat calculator spreadsheets). Individual Level 1 threats frequently score differently for each population, so they are discussed here in order of threat number.

The highest scored threat was Threat 8 (Invasive & other problematic species & genes), which scored High-Medium for the Pacific Coast population but was “Unknown” for Intermountain – Rocky Mountain and Prairie/Western Boreal – Canadian Shield. Medium and Medium-Low threats include Threat 1 (Residential & commercial development) for the Pacific Coast population, Threat 4 (Transportation & service corridors) for the Pacific Coast and Intermountain – Rocky Mountain populations and Threat 7 (Natural system modifications) for the Pacific Coast population. The Prairie/Western Boreal – Canadian Shield population scored only Low threats (see Table 7 for a comparison of threat categories for each population).

Threat 1: Residential and commercial development

Habitat loss, both of productive pond habitat and natural nesting habitat, is a primary threat to the Western Painted Turtle in parts of its range. Complete habitat loss often results when wetlands are filled in for the purposes of residential and commercial development. Habitats that are not lost are often altered by habitat fragmentation of summer and nesting areas, riparian shoreline degradation, changes to local hydrology, and water contamination. Development rates are discussed in the Habitat Trends section for each population. New housing and commercial development is mostly a threat for the Pacific Coast population and particular areas within the Intermountain – Rocky Mountain (e.g., Okanagan Valley) and Prairie/Western Boreal – Canadian Shield (e.g., Regina) populations.

As well as direct threats to Western Painted Turtle habitat, new residential and commercial development also compounds many other threats, especially increased road networks close to water bodies, thereby raising risk of road mortality (Threat 4), invasive species (Threat 8), loss of basking structures and alterations to nesting habitat (Threat 7), increased potential for collecting individuals for pets or consumption (Threat 5), and increased pollution (Threat 9).

Threat 2: Agriculture and aquaculture

In agricultural settings, habitat loss often involves converting wetland to arable lands or pastures. Habitats that are not lost may be impacted by activities such as changes to local hydrology, or nest site degradation due to tilling. Disturbance of shallow wetlands by cattle can cause significant degradation of shoreline and riparian zones in open landscapes of the prairie, foothill and semi-desert rangelands. This physical habitat disturbance is likely more of an issue than cattle fouling water quality. Lindsay and Dorcas (2001) found Painted Turtles in North Carolina were not overly impacted by cattle accessing water bodies. The removal of native plant cover, erosion of banks, soil compaction and water pollution (or eutrophication, if a wetland is overburdened with nitrogenous waste) that follow can all affect turtles. Few new lands are anticipated to be converted for agricultural purposes over the next ten years; however intensification of existing farmlands can be expected, particularly in the agricultural areas of the Pacific Coast population.

Threat 3: Energy production and mining

Energy production and mining are not considered significant threats to populations in British Columbia. Few new mines are anticipated to be opened at the low elevations where Western Painted Turtles occur in British Columbia, and there is no petroleum exploration or development within Western Painted Turtle range in the province. However, in the Prairie/Western Boreal – Canadian Shield population, both petroleum exploration and development, and mining present potential threats. Extensive petroleum development is underway in the southern Saskatchewan Williston basin (Morgan 2014), which directly overlaps with Western Painted Turtle distribution. The greatest impacts are likely the increased road network raising the risk of road mortality (see Threat 4: Transportation and Service Corridors). The amount of direct disturbance to turtles and/or turtle habitat is unknown but may include altered water quantity and quality, especially potential groundwater disturbance from fracking methods used to access petroleum. Mining is a potential localized threat in northwestern Ontario, where there are numerous exploration sites.

Threat 4: Transportation and service corridors

Roads built through or near wetlands are a significant mortality source for Western Painted Turtles and create barriers to migration and dispersal (Gillies and St. Clair 1997; COSEWIC 2006; Griffin 2007; Engelstoft and Ovaska 2013). Mortality has been documented as high as 13% of the estimated local turtle population (Griffin 2007) in a year when western Montana wetland habitats dried up, forcing turtles to move to other ponds. Questionnaire respondents for this report consistently reported road mortality as the primary or secondary threat facing Western Painted Turtles across their range. However, road mortality does not necessarily translate into local population declines. Dorland et al. (2014) tested whether ponds in close proximity to roads suffered population declines relative to ponds without the threat of nearby roads and found no differences.

Road density varies tremendously across the Western Painted Turtle’s Canadian range (Figures 8 and 9). For example, roads are relatively sparse in northwestern Ontario. In British Columbia, however, road densities can be quite high, particularly in the Lower Fraser Valley part of the Pacific Coast population. In the Intermountain – Rocky Mountain population, most high-volume roads are in valley bottoms, the same location as Western Painted Turtles. In the Prairie/Western Boreal – Canadian Shield population, roads are distributed more evenly across the landscape, especially on the Prairies. Traffic volumes on these roads also vary significantly. Petroleum exploration across the southern prairies may significantly increase road densities in the next decade or more in the Prairie/Western Boreal – Canadian Shield population.

Some studies suggest roads impact females primarily because they bisect movement routes between aquatic environments and nearby nesting habitat (Baldwin et al. 2004). Consequently, populations with male-biased sex ratios in wetlands associated with areas of high road density have been observed (Aresco 2004; Steen and Gibbs 2004). Others have found no sex-bias in road mortality (Griffin 2007). Hatchlings are also impacted because they also follow this bisected route from their natal nests back to water bodies.

Roads may also act as an attractant to nesting females as the fill material or exposed cutbanks along roadsides may be ideal nesting substrate. This was the case in Cranbrook, British Columbia, in the late 1990s when Western Painted Turtles in Elizabeth Lake suffered high mortality crossing Highway 3 to access an exposed cutbank as nesting habitat (Gillies and St. Clair 1997).

Road mortality has the potential to alter the structure of turtle populations because turtle life histories are characterized by low annual recruitment rates, high adult survival rates, and delayed sexual maturity (Steen and Gibbs 2004). Together, these features severely constrain the ability of turtle populations to cope with added adult mortality (e.g., Brooks et al. 1991, but see Dorland et al. 2014). Roads also impact genetic diversity of Painted Turtles. Laporte et al. (2013) reported reduced mitochondrial DNA diversity (up to three times fewer haplotypes) in Midland Painted Turtle populations close to roads in eastern Quebec relative to populations without the threat of roads.

Roads have a negative impact on wetland quality, and their influence can extend more than 100 m away (Forman and Deblinger 2000). Road construction immediately adjacent to wetlands can also destroy turtle nests directly (Maltby 2000). Roadways also act as linear corridors facilitating dispersal and foraging strategy of turtle predators including Raccoons, skunks, Coyotes, and foxes (Frey and Conover 2006). Roads surrounding wetlands may thus increase predation rates significantly, particularly for small slow-moving turtles and their relatively accessible eggs.

Threat 5: Biological Resource Use

Western Painted Turtle are sometimes collected as pets, particularly by families with young children. Whether the collection of individuals is great enough to affect local populations is not known, but if it happens repeatedly over the course of a season in an area with an already low turtle population it may be possible to lower local viability. More of a concern, perhaps, is the identification and management of water bodies that are native vs. introduced Western Painted Turtles. Introducing a mid-level predator such as Western Painted Turtle to a new water body is likely to have ecological impacts on that ecosystem. If Western Painted Turtles are already present, introducing potentially very different haplotypes to that population could have fitness consequences.

Collection of long-lived turtles can be problematic because their longevity is associated with low fecundity, delayed sexual maturity, and high adult survivorship: populations cannot remain stable (or grow) when adults and older juveniles are removed at high rates (Congdon et al. 1993; Kiester and Olson 2011). While the pet trade and harvest for food present threats to many turtle species (Gibbons et al. 2000; Kiester and Olson 2011), this is not considered a major threat to Western Painted Turtle in Canada at this time, but it may be an emerging problem for some subpopulations, especially on the Sunshine Coast (Evelyn pers. comm. 2016). Western Painted Turtle harvest in Minnesota was concluded to have likely impacted populations, but whether the substantial harvest was sustainable was unclear (Gamble and Simons 2004). Angling also contributes to turtle mortality; turtles have been found dead as a result of having the bottom of their jaws torn open by hooks, preventing them from feeding (COSEWIC 2006; Welstead pers. comm. 2015).

Forestry impacts are largely restricted to a few sites in the Pacific Coast population in the Sunshine Coast and Alberni Valley areas (Western Painted Turtle Recovery Team 2016) and northwestern Ontario. In British Columbia, regulations rarely require a riparian buffer over 30 m during harvest, which Semlitsch and Bodie (2003) concluded is insufficient for protecting reptiles and amphibians. Forestry activities also require extensive road networks further exposing local populations to road mortality (Threat 4). Forestry activity is considered a negligible threat to Western Painted Turtle in the Intermountain – Rocky Mountain population because there are few merchantable forests around most Western Painted Turtle inhabited wetlands.

Threat 6: Human Intrusions and Disturbance

Adult turtles can be sensitive to disturbance by people and their pets near their nesting grounds (Gervais et al. 2009). Nesting females could abandon their nest excavation attempt if they are bothered by humans or loose pets (Maltby 2000), which could result in their return to the wetland and a new nesting attempt later. This increases the time they spend out of the water and their exposure to predators and road mortality.

Humans can also affect Western Painted Turtles directly by disturbing them at their basking or nesting sites, which is a common occurrence in popular recreation sites (Maltby 2000; COSEWIC 2006) or by capturing turtles for pets (Orchard 1986). Unintended disturbance by digging in sand / fine gravel beaches may disturb eggs or increase the likelihood of nest predation after humans have left. Disease can be a secondary expression of other environmental stressors associated with habitat degradation (Gibbons et al. 2000).

Threat 7: Natural System Modifications

Surface and/or groundwater use may impact turtle habitat (water quantity). Water quantity, particularly in the southern Prairies may be an issue for Painted Turtles. The 30 year (1980 to 2009) average water usage in Missouri and Souris drainages was all considered ‘High’ (more than 40% of available surface water is used) indicating “Severe Stress” (Environment Canada 2012). The Assiniboine watershed was ranked “Moderate” (10 to 20% is used) for the same time period. The only watershed in British Columbia analyzed was the Okanagan. It was ranked “Medium” (20 to 40% of available water is used indicating both water supply and water demand need to be managed). Other areas are deemed to have ‘Low’ water quantity threats with <10% of available water used (Environment Canada 2012).

The overgrowth of nesting grounds with grasses and invasive plants is an important threat to turtles because it limits the amount of available nesting habitat. Vegetation could be used by nesting females for hiding cover but the plant roots can make nest excavation difficult and shading can lower soil temperatures (Maltby 2000). Lower soil temperatures could alter the temperatures of the nests themselves, and thus affect temperature dependent sex determination and sex ratios in hatchlings (Refsnider and Janzen 2012). The lack of nest availability and poor quality of nesting sites close to wetlands may cause turtles to seek more suitable areas to nest, which could lead to increased movement across roadways.

In addition to reducing nesting habitat, invasive plants also pose a direct threat to turtle hatchlings during development. Plant roots have the ability to grow into nests beneath the ground thereby penetrating into eggs and entangling hatchlings (Maltby 2000), causing direct mortality. The roots can physically constrict hatchlings from emerging or encase them completely, causing mortality (Maltby 2000). Increased hatchling mortality compounds naturally low hatchling survivorship (Iverson 1991) and further reduces recruitment (Gervais et al. 2009).

Threat 8: Invasive and Other Problematic Species & Genes

Bullfrogs (Lithobates catesbeianus) are known to predate on hatchlings of both Western Painted Turtles (Jancowski and Orchard 2013) and Western Pond Turtles (Actinemys marmorata) (Sloan 2012). This threat is most pronounced in the Pacific Coast population on Vancouver Island and British Columbia’s Lower Mainland. However, Bullfrogs are also known to occur in the Intermountain – Rocky Mountain population at several locations including: South Okanagan (BC Frogwatch 2015); Nelway, BC, in the West Kootenays (Anderson pers. comm. 2015); within 7 km of the Canadian border in Idaho, upstream of Creston, BC (Beaucher pers. comm. 2015) and a small lake near Brisco, British Columbia (Conroy pers. comm. 2016).

Red-eared Sliders are often released as unwanted pets in many water bodies, mostly documented in the Pacific Coast population. Sliders are now known to successfully breed, at least occasionally, in southwestern British Columbia (Welstead pers. comm. 2015a). In the Lower Mainland, 15% of Western Painted Turtles captured and intended for transplantation had respiratory diseases, possibly transmitted from Red-eared Sliders (Welstead pers. comm. 2015c). There is much uncertainty, however, of the population effects of introduced species, and hence a range is used for the threat severity rating (moderate - serious).

Turtle nest predation by various predators such as Raccoons, skunks, Coyotes, and foxes is very common. In Quebec, raccoons were identified as the number one predator of Painted Turtle nests: 85.7% of nests were destroyed the same night they were laid (Christens and Bider 1987). Nests are at a high risk of predation if they are clumped together and near the shoreline because raccoons are known to forage near pond edges (Marchand and Litvaitis 2004). Predator-destroyed nests are an immediate threat to hatchling survival because eggs are consumed. A nest that has been preyed upon will not only have zero hatchling survival but this will impact the overall structure of the population because no juveniles will be recruited into the population.

Numbers of gulls and Racoons, human commensals, appear to be increasing at some localities, as do those of Great Blue Herons (Ardea herodias) and skunks, which are predators of nests and hatchling turtles. Seasonal cyanobacteria blooms at several sites (e.g., Swan Lake and Beaver Lake on Vancouver Island) may adversely affect turtles, but there are no data. Nest predation in Burnaby Lake is 100% if nests are not protected (Western Painted Turtle Recovery Team 2016). Separation of natural background predation levels from increased predation resulting from human-caused habitat modification is difficult. Therefore, the severity of this threat in the calculators is scored as “unknown”.

There is evidence of hybridization with other subspecies of painted turtles in Burnaby Lake (Jensen et al. 2014b), probably associated with the release of introduced C. picta subspecies sold in pet stores. Long-term impacts of this intra-specific hybridization are not clear.

Threat 9: Pollution

The number of chemicals used for industrial and agricultural purposes continues to grow. Effects of these pollutants on reptiles are poorly known (Pauli et al. 2010). Given that Western Painted Turtles frequently inhabit water bodies within urban areas that frequently collect runoff and discharge from various sources and their opportunity to accumulate toxins over a relatively long lifespan, Western Painted Turtles may be considered to be at significant risk due to pollution. Contaminant exposure is considered one of the six main causes of global reptile declines (Gibbons et al. 2000).

Polychlorinated biphenyls (PCBs), organochlorine pesticides, dioxins and furans can accumulate in the tissues of aquatic organisms, including turtles. In the industrial region of southern Ontario, toxic residues in the liver and adipose tissue of Snapping Turtles (Chyledra serpentina) are commonly above human consumption guidelines (de Solla and Fernie 2004). High levels of these toxins bioaccumulate in long-lived Snapping Turtles. Given that Painted Turtles live at least as long as Snapping Turtles (Congdon et al. 2003; Samson 2003), adult Painted Turtles may be expected to also carry high levels of such residues at sites where these chemicals are at high concentrations in the aquatic environment. In a study of Eastern Spiny Softshells (Apalone spinifera) in southern Ontario, for example, de Solla et al. (2003) found that PCB and pesticide contaminant concentrations were positively correlated with egg viability, although there was no evidence for any negative effect of PCBs or pesticides upon hatching success. Crews et al. (1995) noted that PCBs can alter Painted Turtle population structure by reversing gonadal sex at otherwise male-producing temperatures. Although central and western Canada are not generally exposed to the same intensity of industrialization, pesticides, herbicides and chemical fertilizers are used throughout rangelands, croplands, vineyards, and orchards. Some wetlands may be more affected than others by toxic infusions depending on bathymetry, hydrology, and exposure to the chemicals (proximity and concentrations). Despite their widespread applications, very little research has been conducted on the effects of these pesticides on reptiles, including turtles (Pauli et al. 2010).

Glyphosate herbicides have been observed being sprayed over Western Painted Turtle nests at Nicomen Slough in the Pacific Coast population. In Red-eared Sliders, glyphosate has been shown to reduce hatching success and result in genetic deformities, though at higher doses than are typical in most applications (Sparling et al. 2006 in de Solla 2010).

A number of emerging pollutants including fungicides, perfluorinated chemicals (PFCs), brominated flame retardants, anionic surfactants and antibiotic materials also have been shown to accumulate in various turtle species (McConnell and Sparling 2010). Few impacts have yet been shown, mostly due to lack of research. One study found sex-reversal in snapping turtles during incubation at temperatures that typically favour males (Place et al. 2001).

Most pollution contamination occurs in large urban areas, including British Columbia’s Lower Mainland (Pacific Coast population). Lost Lagoon in Vancouver’s Stanley Park is primarily a storm water retention pond. Many other water bodies in British Columbia are also very close to roadways and will suffer from contaminated runoff. Many lakes in the Lower Mainland are also closed to public swimming due to high coliform levels. Impacts of this pollution on Western Painted Turtles are not known, though in North Carolina, Painted Turtles did not show adverse effects from cattle accessing and fouling the water (Lindsay and Dorcas 2001).

Threat 11: Climate Change and Severe Weather

Climate change is likely to have variable impacts throughout the Western Painted Turtle’s range. In British Columbia, particularly in the Southern Interior, predicted changes are generally for warmer and wetter conditions overall. However, most precipitation is anticipated in the winter months (as more rain than snow, particularly at low elevations where turtles occur), while summers and early autumn are predicted to be much drier (Murdock and Werner 2011; Hamlet et al. 2013). On the Prairies, more significant drying is also anticipated (Sauchyn and Kulshreshtha 2008). Climate change may also impact water availability, compounding other demands on water (see Threat 7: Natural System Modifications).

Climate change is hypothesized to negatively impact species with temperature-dependent sex determination, such as Painted Turtles, by biasing sex-ratios (Janzen 1994). Female turtles have been shown to show plasticity in the timing of nesting and selection of nesting sites, suggesting that females may exert some control over the thermal conditions of their nests (Janzen and Morjan 1997; Schwanz and Jansen 2008). As such, the ability of females to adapt their breeding phenology in response to changing environmental temperatures is possible, although summer temperatures post-laying may have a stronger effect in determining hatchling sex-ratios (Schwanz and Janzen 2008).

An increase in mean temperature associated with climate change could severely impact turtles by resulting in single sex populations (Mitchell et al. 2008); however, others suggest temperature fluctuations may result in different outcomes (Escobedo-Galvan 2013). This may not be important for Canadian populations, however, that exist at the northern limits of the species’ global distribution, which extends much farther south where populations are naturally experiencing temperatures similar to those expected under climate change.

Number of locations

The most logical threat-based location for Western Painted Turtle would be at the water body or drainage level. For British Columbia and Ontario, this would be a pond or small lake that could be removed or have its habitat altered relatively rapidly by some threat (e.g., chemical spill, infill, drying up), affecting all turtles within the site. In some cases, this may a larger wetland complex (e.g., Creston Valley wetlands in southeast British Columbia may be one “location”).

If the water body level is used, there are 82 known locations in the Pacific Coast population (BC Ministry of Forests, Lands & Natural Resource Operations unpubl. data). However many of these likely do not support self-sustaining populations. The Intermountain – Rocky Mountain population has approximately 200 discrete water bodies with turtle observations, which may qualify as locations.

Estimates for the Prairie/Western Boreal – Canadian Shield population is more difficult because Western Painted Turtles on the prairies are more riverine than elsewhere, though many of their occurrences are in isolated oxbow lakes. The best fit of a location may then be some unquantified distance or reach of a river. Regardless, the number of locations for the DU is well into the hundreds when inhabited lakes and ponds in the Canadian Shield faunal province are taken into account.

If numerous water bodies in close proximity are taken as a location, then the number of locations will be reduced (e.g., the Pacific Coast has 36 “population units” that combine water bodies in close proximity). Potential for catastrophic wildfire, disease outbreak, drought or other threats could potentially threaten Western Painted Turtles at a more regional scale. The total number of locations under this scenario is more difficult to estimate, but still likely to be well over ten for each population

Protection, status and ranks

Legal protection and status

The Pacific Coast population (also known as “Pop. 1” in British Columbia) and Intermountain – Rocky Mountain population (“Pop. 2” in British Columbia) of the Western Painted Turtle are both listed on Schedule 1 of the federal Species at Risk Act in 2007 as Endangered and Special Concern, respectively.

In British Columbia, Western Painted Turtles are included under the provincial Wildlife Act, which prohibits the killing, collection, and harassment of all native vertebrates without a permit. General possession of Western Painted Turtles is not permitted under provincial Wildlife Acts for British Columbia, Alberta, and Saskatchewan, except by permit or licence. In Manitoba, the Western Painted Turtle was declared a protected species in 2015 and moved into Division 6 of the provincial Wildlife Act; as a result taking of individuals for personal use is no longer allowed. Ontario’s Fish & Wildlife Conservation Act prohibits possessing or killing the Western Painted Turtle, which is listed as a “specially protected reptile” under that Act’s Schedule 9. Although Alberta ranks Western Painted Turtle as S1 (Table 8) based on very limited native range, it is not included on the province’s list of Endangered Species under the Alberta Wildlife Act (Government of Alberta 2014).

^h NatureServe rankings: G: Global; N: National; S: Subnational; 1: critically imperilled; 2: imperilled; 3: vulnerable to extirpation or extinction; 4: apparently secure; 5: demonstrably widespread; abundant; and secure; NA: not applicable; NR: unranked (Rank not yet assessed). A range of ranks indicates uncertainty. T: indicates an infraspecific taxon ranking.

Non-legal status and ranks

Western Painted Turtle has a global ranking of G5T5 (“demonstrably widespread; abundant; and secure”). National rankings at the subspecies level also indicate the subspecies is secure when its entire range is taken into account (Table 8). Subnationally, status ranks for Western Painted Turtle vary taxonomically by jurisdiction. Many United States states within the Western Painted Turtle’s range do not rank it to the subspecies level (Table 8). Subnational status ranks in Canada range from S1 (Alberta) to S4 (Manitoba). Several states rank Painted Turtle or Western Painted Turtle as S5, but no jurisdiction in Canada considers it demonstrably secure (ranking of S5).

In British Columbia, the Pacific Coast (Pop. 1) population is “red listed” by the BC Conservation Data Centre, while the Intermountain – Rocky Mountain (Pop. 2) population is “blue listed”. These listings are analogous to their respective federal ‘Endangered” and “Special Concern” status but carry no legislated protection.

Habitat protection and ownership

Across their Canadian range, Western Painted Turtles inhabit a range of crown (mostly provincial, some municipal and federal) lands and private lands. A provincial recovery plan for the Pacific Coast population (SARA Schedule 1 ‘Endangered’) has been finalized, including Critical Habitat description (Western Painted Turtle Recovery Team 2016), but Critical Habitat has not been identified under SARA. Where they occur on federal land, Western Painted Turtles in the Pacific Coast population receive protection under SARA. The following sites occupied by Western Painted Turtle are federal land: Alaksen National Wildlife Area, Nicomen Slough, Silvermere, and the Great Blue Heron Nature Reserve, all within the Lower Mainland/Fraser River Valley (turtles in Greenburn Lake, Pender Island, within the Gulf Islands National Park Reserve appear to be C. p. picta rather than C. p. bellii; Paleczny pers. comm. 2014). The Western Painted Turtle Recovery Team (2016) states that 36% of the known sites occur on private lands and that “most” sites occur in parks or protected areas managed by regional/municipal, provincial, or federal governments.

In the Intermountain – Rocky Mountain population, Western Painted Turtles occur in the Vaseux-Bighorn National Wildlife Area in the Okanagan and may occur in the Columbia National Wildlife Area in the East Kootenay region of British Columbia. They occur in numerous provincial parks and regional / municipal parks.

In the Prairie/Western Boreal – Canadian Shield population, Western Painted Turtles are occasionally reported from Waterton Lakes National Park, but these are considered introduced (Johnston pers. comm. 2014). They are known from both Grasslands National Park in Saskatchewan and Riding Mountain National Park in Manitoba.

In British Columbia, threats posed by residential and commercial development may be addressed at least partially at the municipal level. Best management practices are available (Ovaska et al. 2004) but have no legal backing. Numerous regional districts (analogous to counties) have bylaws under official community plans that require development permit approvals. Such municipal tools may help reduce or mitigate development but are seldom legally binding. Other provincial legislation in British Columbia may provide some protection to Western Painted Turtle habitat features: Riparian Areas Regulation, Fish Protection Act, and the Water Sustainability Act.

Acknowledgements and authorities contacted

Cover photo by Ben Meunier (Cranbrook, British Columbia). GIS work by Jenny Wu (COSEWIC Secretariat). Logistic support by Kristiina Ovaska (COSEWIC Amphibians and Reptiles Co-chair), Monique Goit, Bev McBride and Angele Cyr (COSEWIC Secretariat). We thank all staff and representatives of the provincial ministries, federal departments, and conservation data centres, and the researchers and consultants who provided data, responded to requests for information, and reviewed drafts of this report. Special thanks to Kristiina Ovaska for shepherding the report through numerous edits and stages and very helpful edits and recommendations. Comments by the Amphibian and Reptile SSC members greatly improved this report.

Adama, Doug. Wildlife Biologist, LGL Environmental Research Consultants Ltd. Sidney, BC.

Basaraba, Nicole. Summit Environmental Consultants. Vernon, BC.

Beaucher, Marc-André. Head of Operations Creston Valley Wildlife Management Area, Creston, BC.

Didiuk, Andrew. Wildlife Biologist. Canadian Wildlife Service. Saskatoon, SK.

Dzilums, Andy. River Guide (former). Fairmont Hot Springs Resort. Fairmont Hot Springs, B.C.

Englestoft, Christian. Wildlife Biologist. Alula Consulting. Victoria, BC.

Evelyn, Michelle. Research Affiliate, UBC Biodiversity Research Centre, University of British Columbia, Vancouver, BC.

Gregory, Patrick. Professor, University of Victoria. Victoria, BC.

Halverson, Larry. Park Naturalist (ret’d), Kootenay National Park, Parks Canada. Radium Hot Springs, BC.

Hawkes, Virgil. Wildlife Biologist, LGL Environmental Research Consultants Ltd. Sidney, BC.

Hobbs, Jared. Wildlife Biologist, Hemmera Inc. Victoria, BC.

Johnston, Barb. Wildlife Biologist. Waterton Lakes National Park. Waterton Lakes, AB.

Kendell, Kris. Senior Biologist, Alberta Conservation Association. Edmonton, AB.

Leeming, Amy. Graduate Student, Thompson River’s University. Kamloops, BC.

Machmer, Marlene. Wildlife Biologist. Pandion Ecological Research. Nelson, BC.

Matthias, Laura. Biologist, Salt Spring Island Conservancy, Ganges, British Columbia.

Ohanjanian, Penny. Wildlife Biologist. Kimberley, BC.

Ovaska, Kristiina. Wildlife Biologist. Biolinx Environmental Research Ltd., Victoria, BC.

Quinlan, Richard. Instructor - Environmental Science, Lethbridge College. Lethbridge, AB.

Rutherford, Pamela. Associate Professor, Brandon University. Brandon, MB.

Walker, Lee-Anne. Naturalist. Fernie, B.C.

Watkins, Bill. Biodiversity Conservation Zoologist. Manitoba Conservation and Water Stewardship. Winnipeg, MB.

Wind, Elke. Consulting Herpetologist. Nanaimo, BC.

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Biographical summary of report writers

Ian Adams has over 20 years of wildlife biology experience, working from Ontario to the west coast and Yukon. He specializes in species at risk management and recovery. This is his third COSEWIC status report, previously writing American Badger (2012) and Southern Flying Squirrel (2006). Ian holds an MSc in Wildlife Ecology from University of Guelph and has been based in the East Kootenay region of British Columbia since 1997.

Leigh Anne Isaac specializes in reptile and amphibian ecology. She has participated in various inventory and assessment projects for Western Painted Turtle in the Kinbasket and Revelstoke reservoirs in British Columbia. Most recently, Leigh Anne completed fieldwork on a multi-year study of Painted Turtles at Creston, BC (Intermountain-Rocky Mountain DU) which focused on population structure, habitat use, movement patterns and threat impact assessment that will directly inform recovery work for this species. As an adjunct professor at Thompson Rivers University, Leigh Anne sits on graduate student committees contributing to master’s projects such as Western Painted Turtle winter ecology.

Collections examined

No collections were examined for the preparation of this status update report.

Appendix 1. Threats assessment for the Western Painted Turtle – Pacific Coast Population.

Threats assessment worksheet

Appendix 2. Threats assessment for the Western Painted Turtle – Intermountain – Rocky Mountain Population.

Threats assessment worksheet

Appendix 3. Threats assessment for the Western Painted Turtle – Prairie/Western Boreal – Canadian Shield Population.

Threats assessment worksheet