Management Plan for The Western Painted Turtle (Chrysemys picta bellii ) in the Alouette River Watershed
April 2012
Prepared for: BC Hydro’s Bridge Coastal Fish and Wildlife Restoration Program 6911 Southpoint Drive (E14) Burnaby, BC V3N 4X8
And Kym Welstead Ministry of Forests, Lands and Natural Resource Operations 10470 152 nd Street Surrey, BC V3R 0W8
BCRP Report No. 11.ALU.W.01
Prepared by: Aimee M. Mitchell, M.Sc., RPBio . 103-1516 E. 1 st Avenue Vancouver, BC V5N 1A5
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Abstract In 2011, funding was approved for the Bridge Coastal Restoration program project titled “Identify, conserve and restore populations of priority species at risk and their associated habitats within the Alouette River Watershed.” One of goals of this project, in cooperation with Western Painted Turtle Recovery program, is to identify sites occupied by Western Painted Turtles ( Chrysemys picta bellii ), and assess the available habitat, including potential threats, as well as opportunities for restoration. To properly assess these features, a detailed plan was developed to facilitate efficient surveys of any and all potential habitat within the Alouette Watershed, incorporating the North and the South Alouette drainages.
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Contents
Abstract ...... ii Background/Rationale ...... 1
Status ...... 1
Threats ...... 2
Species Description ...... 2
Sampling Area and Habitat Description ...... 3
Methods ...... 4
Site Delineation ...... 4
Survey Methods ...... 5
Materials Required ...... 6 Scheduling ...... 6 Data Collection: ...... 7 Management Recommendations ...... 7
Appendix I: Site Management Plan for Jerry Sulina Municipal Park ...... 10 Appendix II: Survey Site Codes ...... 10 Appendix III: Survey Site Data Sheet ...... 11 Appendix IV: Turtle Occurrence Survey Data Collection Form ...... 12 Appendix V: Habitat and Threat Assessment Data Collection Form ...... 13 Appendix V: Survey Overview Maps ...... 14
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Management Plan for The Western Painted Turtle (Chrysemys picta bellii ) in the Alouette River Watershed
Background/Rationale The goal of the project is to identify, conserve and restore priority species at risk and their habitat within the Alouette River watershed. Western Painted Turtles (Chrysemys picta bellii ) were selected as a priority species, due to their high conservation framework ranking, as well as the abundance of opportunities for conservation, restoration and stewardship. Specifically these goals will be achieved through these objectives: 1. Mapping Western Painted Turtle occurrences, as well as their habitat to guide future conservation, restoration and stewardship efforts. 2. Identifying specific threats to the Western Painted Turtle, protecting occupied sites, and restoring degraded habitat. 3. Preventing further population declines, habitat loss and degradation through increased accessibility to data, as well as public outreach and education designed to enhance awareness and stewardship of the species and its habitat. Previous surveys in the area have only confirmed one occurrence, at Jerry Sulina Municipal Park in 2007 (Semproni, 2007). However, very few other water bodies in the watershed have been properly assessed. In order to establish the true extent of the population within the watershed, it is imperative that a thorough survey of the entire area be conducted.
Status The federally endangered and red-listed Pacific Coast population of the Western Painted Turtle (Chrysemys picta bellii ) is in danger of becoming extirpated in British Columbia (COSEWIC, 2006). This species currently occupies 71 known sites across the south coast of B.C., from the Lower Mainland/Fraser River Valley through parts of Vancouver Island, some Gulf Islands, and up through the Sunshine Coast as far north as Powell River and Texada Island (Western Painted Turtle Recovery Team, 2010; Unpubl. data, 2011). Across its range, the Pacific Coast Western Painted Turtle inhabits shallow lakes and wetlands. Its range coincides with some of the most densely populated areas of British Columbia, and the habitat in which it lives has been hardest hit by unsustainable development practices. It is estimated that over 87% of the wetlands and shallow lakes on the south coast of B.C have been lost due to agriculture and expanding urbanization (Boyle, 1997). Remaining wetlands and riparian habitats are degraded and lack critical habitat features needed to sustain the endangered Western Painted Turtle and associated species at risk.
Currently, 16 occupied sites are known in the Lower Mainland/Fraser Valley, with nearly all of the populations in the region at risk of extirpation, with less than 20 individuals present (Kilburn and Mitchell, 2011; A. Mitchell, 2011). Of these 16 sites only one exists in the Alouette Watershed and the 1
1 individual observed at that site, Jerry Sulina Municipal Park, has not been observed since 2007 (Semproni and Oglivie, 2007). Within the watershed the Western Painted Turtle is listed as species of high conservation concern in the BC Hydro Alouette Watershed Species of Interest Action Plan , with reference to habitat restoration and possible reintroduction as ways to support species recovery in the watershed (BC Hydro, 2011). The site management plan for the currently occupied site is provided in this document (Appendix I)
Threats The Western Painted Turtle faces a variety of threats including; residential and commercial development, agriculture and aquaculture, energy production and mining, transportation and service corridors, biological resource use, human intrusions and disturbance, natural system modifications, invasive and other problematic species and genes pollution, and climate change and severe weather (as listed as Threats 1-10 in Recovery Strategy, The Western Painted Turtle Recovery Team, 2010). In order to best promote recovery for painted turtles, sites need to first be identified and threats assessed. Actions to mitigate these threats are then proposed. Recommendations for the site-specific threats for occupied sites or sites with potentially suitable habitat will be provided in this document.
Species Description The Western Painted Turtle ( Chrysemys picta bellii ) is the only remaining freshwater turtle native to British Columbia (The Western Painted Turtle Recovery Team, 2010). It has a low domed, unkeeled carapace that is dark green to brown, sometimes with wormy patterns in smaller turtles, particularly males (Gregory and Campbell, 1987, Conant and Collins, 1998 and Pers. obs. Mitchell and Currie, 2011). The plastron and bridge are bright orange-red with intricate patterns of dark and light colours that extend to the edge of the plastron. The head legs and tail are dark green with irregular bright yellow stripes (Macartney, 1985) (Figure 1). Females are generally larger than males, reaching lengths of up to 25 cm, while males rarely reach more than 20 cm. Males have long front claws (females front claws are typically less than 1.1cm) and their cloaca is located farther down on the tail (Iverson, 1993) (Figure 2).
Figure 1. The dark carapace, intricately patterned orange-red plastron and yellow-striped head, legs, and feet of the Western Painted Turtle.
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Figure 2. The different position of the cloaca along the tail in male (left) and female (right) Western Painted Turtles
Although the Western painted Turtle is the only extant native turtle in British Columbia, it often occurs with other introduced species, particularly the Red-eared Slider (Trachemys scripta elegans ) which it may be confused with. The Red-eared Slider is distinguished by its higher domed, slightly keeled carapace, yellow plastron and marginal scutes, and a prominent red stripe on the side of the head (Figure 3).
Figure 3. The native Western Painted Turtle (left) compared with the introduced Red- eared Slider (right).
This stripe may become faded in older individuals, and several other species of pet turtles have been found released in the lower mainland, so care in identification must be exercised. Another possibility that may confound proper identification is the existence of another subspecies of Chrysemys picta , the Midland Painted Turtle (Chrysemys picta marginata. ) Although these subspecies are relatively simple to distinguish, where they occur together, they have been found to breed and intergrades do occur. In general Midland Painted Turtles have a paler plastron, with far less intricate markings that do not reach the edge of the plastron(Weller, 2010) (Figure 4).
Sampling Area and Habitat Description Figure 4. Typical plastron patterns of C. p. bellii (left), typical intergrade (centre), and C. p. marginata (right).
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All potential Western Painted Turtle habitat within the Alouette River watershed is to be surveyed for turtles between 2011 and 2016. All permanent water bodies in the watershed with potential habitat were identified by examining orthophotos, and digitized in ARCGIS. Coastal populations of Western Painted Turtles have only been found at elevations below 300m (Kilburn and Mitchell, 2011; M. Evelyn, unpub. data, 2009); therefore any water bodies at higher elevations were not considered. A total of 40 sites were digitized, and numbers assigned to each (Appendix I). A number of these sites are made up of numerous individual water bodies; therefore it is imperative that precise locations be recorded during surveys.
Approximately 63.4 km of linear habitat (rivers, sloughs and ditches) and a further 141.3 ha of ponds, lakes and wetlands with 34.7km of shoreline have been identified as potential habitat within the watershed. Many of these sites however may only need to be assessed once if it is determined that they do not provide habitat for turtles. The identified sites are all within the municipalities of Maple Ridge and Pitt Meadows. Many are located on municipal or provincially controlled lands. A large number however, are on private land, and ownership needs to be established, and landowners contacted in order to gain permission to access these sites.
The water bodies to be surveyed can be roughly broken into five areas. Three of the areas are in the lower watershed, which contains the highest concentration of potential habitat. The other two areas area consists of several ponds lakes and wetlands scattered throughout the rest of the watershed, including the Malcolm Knapp Research Forest. These five general areas are: (See Appendix IV) 1. The Alouette River below the confluence of the North Alouette and South Alouette rivers, and the sloughs and ponds on the north side of the river. 2. The North Alouette and South Alouette Rivers below 224 th street as well as the off channels, sloughs ponds and irrigation ditches between the rivers. 3. Blaney Creek, and the adjacent sloughs, ponds and ditches, including the Codd Wetlands. 4. Lakes and wetlands Within the Malcolm Knapp Research Forest 5. All other potential habitat, generally east and upstream of the aforementioned areas.
Methods
Site Delineation The area of interest was delineation using an ‘Assessed Watershed’ Geographic Information Systems (GIS) layer from the provincial government site providing public access to GIS information, the GEOBC Gateway (source: http://geobc.gov.bc.ca/) and from description and map provided in the BC Hydro Alouette Watershed Plan (BC Hydro, 2011). Historic observations were also searched for through the Conservation Data Centre (CDC) (source: http://www.env.gov.bc.ca/cdc/ ), whose data layers are also available through the GEOBC Gateway (See Appendix V ).
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Survey areas were identified by interpreting orthophotography of the Alouette watershed. Western Painted Turtles are known to inhabit sloughs, ditches, ponds and slow moving streams in lowland areas of British Columbia (COSEWIC Canadian Wildlife Service, 2006) These areas were identified by assessing the texture, colour, shape, and location of features in several sets of orthophotographic images. Imagery used included SPOT 15 Imagery GVRD Imagery (2004 GEOBC) as well as Google Earth satellite imagery (2010 Google). As well the Freshwater Atlas maintained by the British Columbia Integrated Land Management Bureau (Integrated Land Management Bureau, 2008) was consulted to determine the status of questionable waterbodies. Areas known to be unviable habitat were eliminated.
Survey Methods For occurrence surveys, the guidelines and protocols set out by the Resource Information Standards Committee’s Inventory Methods for Pond-breeding Amphibians and Painted Turtle will be followed. These standards can be found online at: http://www.ilmb.gov.bc.ca/risc/pubs/tebiodiv/index.htm#amphibs
The most effective way to search for Western Painted Turtles is to look for basking turtles on warm sunny days with little to no precipitation (Lefevre, 1995). Turtles will haul out of the water and lay on logs, rocks, floating vegetation or manmade structures to raise their body temperatures. For this reason, observations are far more likely during sunny days, although if air temperatures are considerably higher than water temperatures, they may bask in seemingly adverse weather conditions. Surveys are to be conducted during the warmest part of the day, between 9:00 and 15:00.
Seasonally, the best time to survey for turtles is during the spring nesting season, when females need to bask in order to raise their body temperatures high enough to be able to dig and lay their nest.
If the area to be searched is small enough, and all areas of the site can be seen, search from shore with binoculars. If the lake is too large to be effectively searched form shore, search the entire lake from a small boat.
Painted Turtles can be highly sensitive, and will quickly dive into the water if disturbed. Scan distant areas for basking turtles, then approach slowly to get a better look to identify species, sex and size. Wearing polarized glasses will help to cut glare, and allow surveyors to see turtles swimming below the surface of the water.
Since all of the sites identified in the Alouette watershed are of a small enough size, no stratification is necessary, and all sites should be systematically searched. Surveys are to be conducted at appropriate intervals from the March through to the end of September. Each site should be visited three times. If no turtles are observed after that amount of effort, they are likely not present (Resources Inventory Committee, 1998).
Search effort should be recorded precisely in the event that it may be used to calculate relative abundance.
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Standardized data sheets developed by the Coastal Painted Turtle Working Group will be provided, and must be filled out in full. Information to be recorded will include: (See Appendix II )
• Date, and start/end time of survey • Survey method (foot, kayak etc.) • Air and water temperature • Cloud cover • Precipitation • Species • Sex (if possible) • Location (use a handheld GPS) • Behavior • Associated habitat feature • Invasive/introduced species present
An assessment of the habitat including potential threats and potential for restoration will also be completed at each site. Information to be recorded will include: (See Appendix III )
• Water body type (pond, slough, lake etc.) • Bottom substrate material • Dominant aquatic vegetation • Percent and type of vegetation cover (aquatic, riparian and upland) • Available nesting habitat (type and quality) • Basking habitat • Nesting habitat • Overwintering habitat
Materials Required • Hip/chest waders and boots • Binoculars • Spotting scope • Canoe/kayak • Lifejacket • Handheld GPS • Thermometer • Waterproof notebook • Data collection sheets • Pencils
Scheduling Scheduling will be determined as the field season progresses. Priority should be given to sites close to the confirmed occurrences (as of yet only Jerry Sulina Park), and those that appear to be higher quality habitat. Ideally sites close together can be surveyed on the same day. Since potential sites were
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selected by interpreting orthophotography from 2009, some may not be viable habitat, or may have been developed in the time since the imagery was taken. After the first visit to each site, if it is determined that there is little or no habitat, those sites can be eliminated or moved to the lowest priority for future site visits.
Each site will be visited three times throughout the survey season (March to October.) To ensure that no seasonal bias occurs between sites, surveys should be evenly spaced throughout the year. Ideally, each site will be visited once in the spring (March-May) once during nesting season (June-July) and once in late summer/fall (August September.) During periods of inclement weather, surveys should be suspended, depending on time constraints. Some areas are much larger than others, and some may take several days to complete. In these cases, careful documentation of the exact area surveyed is essential to ensure any data analysis will not be compromised. During the 2011-2012 project year, 12 out of 41 sites delineated (29%) were surveyed for their first attempt (all but one during late summer/fall). During these surveys no detections of Western Painted Turtles were obtained.
Data Collection Data will be recorded on the data sheets provided. General information can be recorded in a waterproof notebook, and digitized at the end of each field day. All data collected is to be entered into various databases, and presented to the Ministry of Forests Lands and Natural Resource Operations, the Bridge Coastal Restoration Program, and the British Columbia Conservation Foundation. Data may also be shared with various community and First Nations groups.
Management Recommendations Current management recommendations for the Alouette River Watershed for occupied Western Painted Turtle sites are encompassed in the Site Management Plan for Jerry Sulina Municipal Park (Appendix I ), the only currently designated occupied site in the watershed. Management recommendations for any further identified occupied sites in the watershed will be based on site-specific threat assessments, including assessing the threats listed above. Recommendations for currently unoccupied but suitable or potential habitat (identified in the survey plan) will be made based on survey results and where feasible restoration efforts may be recommended at sites identified as highly suitable and have potential as an augmentation site in the future. Since the first year of the project was largely devoted to developing a survey plan and monitoring the existing occupied turtle site, limited survey results are available. The Western Painted Turtle Recovery Team is currently reviewing and assessing the feasibility of augmentation (via head-started hatchlings) for turtle populations with high risk of extirpation, many of which exist in the Lower Mainland/Fraser Valley. Currently, restoration efforts proposed are focused on Jerry Sulina Municipal Park. Consultation has been conducted with the District of Maple Ridge for this restoration and there are plans to implement restoration efforts in 2012
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Works Cited
BC Hydro. (2011). Alouette Watershed Species of Interest Action Plan . Final Draft. October 2011. Fish and Wildlife Compensation Program.
Boyle, C.A., L. Lavkulich, H. Schreier, and E. Kiss. 1997. Changes in land cover and subsequent effects on lower Fraser Basin ecosystems from 1827 to 1990. Environ. Manage. 21:185–196.
Conant, R. and J.T. Collins. (1998). A field Guide to Reptiles and Amphibians of Eastern and Central North America. Third edition, expanded. The Peterson Field Guide Series. Houghton Mifflin Co., New York, NY.
Committee on the Status of Endangered Wildlife in Canada (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, Ontario. vii + 40 pp.
Gregory, P.T. and R.W. Campbell. (1987). The Reptiles of British Columbia. B.C. Prov. Museum Handbook. Minist. of Prov. Secret. and Gov. Serv. Victoria, BC.
Iverson, J. a. (1993). Reproductive Ecology of the Painted Turtle ( Chrysemys picta ) in the Nebraska Sandhills and Across It's Range. Copeia , 1:1-21.
Kilburn, V. L. and A. M. Mitchell. (2011) Recovery of the Western Painted Turtle and Associated Species at Risk on the South Coast of BC. 2010-2011 Final Report. Prepared for the B.C. Ministry of Environment.
Lefevre, K. a. (1995). Effects of sex and body size on basking behaviour in a northern population of painted turtle, Chrysemis picta. Herpetoligica , 51(2):217-224.
Macartney, M. a. (1985). The Western Painted Turtle in Kikomum Creek Provincial Park. Victoria, B.C.: Department of Biology, University of Victoria.
Resources Inventory Committee. (1998). Inventory Methods for Pond-breeding Amphibians and Painted Turtle. Standards for Components of British Columbia's Biodiversity No. 37. Victoria, B.C.: Government of British Columbia. Minisrty of Environment Lands and Parks. Resources Inventory Branch for the Terrestrial Ecosystems Task Force Resources Inventory Committee.
Semproni, M. and F. Ogilvie(2007). Western Painted Turtle (Chrysemys picta bellii ). Presence / Not Detected Survey Lower Mainland Region. Summer 2007 Victoria: BC ministry of Environment.
Weller, W. F. (2010). Quantitative Assessment of Intergradation Between Two Subspecies of Painted Turtle, Chrysemis picta belii and C.p. marginata, in the Algoma District of West Central Ontario, Canada. Herpetological Conservation and Biology , 166-173.
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The Western Painted Turtle Recovery Team. (2010). Draft Recovery Strategy for the Western Painted Turtle (Pacific Coast Population), Chrysemys picta bellii , in British Columbia (March 2010). Original version prepared by Vanessa Kilburn for the B.C. Ministry of Environment, Victoria, BC. 45 pp.
Personal communications and sources of unpublished data
M. Evelyn. Research Biologist, Sunshine Coast Wildlife Project and Ruby Lake Lagoon Nature Reserve Society. Pender Harbour, BC. Email: [email protected]
A. Mitchell. 2011. Research Biologist, South Coast Western Painted Turtle Project. Vancouver, BC. Email: [email protected]
Photo and Research Credits
Title Page: David Stiles (left) and Aimee Mitchell (right)
Figure 1: Chris Currie (left and right) and Aimee Mitchell (centre)
Figure 2: Aimee Mitchell (left) and Justin Hyde (right)
Figure 3: Vanessa Kilburn
Figure 4: Casper (left), Alexis McEwan (centre) and Wayne Weller (right)
Christopher Currie of the South Coast Western Painted Turtle Recovery Project (SCWPTRP) contributed significant effort to literature review and synthesis as well as mapping for this species management plan in the Alouette Watershed. In addition, Christopher Currie, Aimee Mitchell, Justin Suraci and Vanessa Kilburn of the SCWPTRP contributed background survey information and links to outreach and restoration initiatives at the currently occupied site, Jerry Sulina Municipal Park, including sign posting and partnership with the District in Maple Ridge for habitat restoration at this site.
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Appendix I: Site Management Plan for Jerry Sulina Municipal Park
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JERRY SULINA PARK, MAPLE RIDGE, BC: SITE MANAGEMENT PLAN
Prepared by
Aimee Mitchell, Vanessa Kilburn, Justin Suraci, and Chris Currie
of the
The SouthCoast Western Painted Turtle Recovery Project
For
Kym Welstead, Ministry of Environment, Surrey, BC
and
Joanne Neilson, BC Conservation Foundation, Surrey, BC
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Site Description
Overview Jerry Sulina Municipal Park is a 6.28 ha park on the corner of 132 nd Avenue and 210 th Street in Maple Ridge B.C. The park is part of a much larger network of trails that run along the extensive dyke system in Maple Ridge and Pitt Meadows. There are two sloughs within the park that are contained by a dyke on the South and East banks and receive water from the adjacent South Alouette River. Water levels in the sloughs fluctuate seasonally, and are also slightly influenced by daily tides. The area receives a great deal of use by cyclists, horseback riders, joggers and particularly dog walkers who use the off leash area adjacent to the two sloughs. The surrounding area is almost exclusively agricultural land with many blueberry farms and hay fields. This park has high recreational use and has a popular section for off-leash dogs on the southern edge of the main pond 1.
Aquatic Habitat Aquatic habitat at Jerry Sulina Park is comprised of two sloughs that occupy 15.2 ha. Both sloughs have ample emergent and submergent vegetation. Dominant species include Asian Water Lily (Nymphaea odorata ), Millfoil ( Myriophyllum spp.), and Reed Canary Grass ( Phalaris arundinacea). The larger slough on the south side of the park has more open water and is less affected by seasonal and tidal changes in water levels. Bottom substrate is composed of sand at the perimeter adjacent to the trails and dykes, with organic detritus being the main substrate material in the less disturbed, more Figure 1. Red-eared Slider basking at pond at Jerry Sulina natural areas of the sloughs. Water depth is shallow, Municipal Park in 2010 (Photo by V. Kilburn) and rarely reaches 2 m. There is some large woody debris --both floating and attached to the shore-- that provide some basking opportunities for turtles.
Nesting Habitat There are several areas around the park that could serve as nesting habitat. There is sandy/gravelly material along the dykes and interior pathways, as well as two sand beaches on the larger slough. However, all of these areas are highly impacted by human use, particularly the large sand beach that serves as an off-leash dog area. There has been no recorded evidence of nesting activity at any of these sites. Most of the shoreline is covered with vegetation that may be encroaching on potential nesting habitat.
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Turtle Populations One Western Painted Turtle was identified at the site in 2007 by the BC Conservation Corps 1 However, in subsequent surveys from 2009 to 2011, only invasive turtles were observed. If the Western Painted Turtle inhabits this site, it is likely that there are only a small number of individuals. This population thus may not represent a true population, and it is possible that individuals occupying this site may have been a released pet. Certainly, there is anecdotal evidence that this species has been moved around by humans in other locations on the south coast of B.C. However it is possible that the Western Painted Turtle could have arrived at this site independently of humans following construction of the sloughs. The nearest known occupied sites are Minnekhada Regional Park and DeBoville Slough across the Pitt River, 7.1 kms away. These sites are connected via aquatic habitat (The mouth of Deboville Slough, which is connects to Minnekhada via a creek, is near the confluence of the Alouette and Pitt Rivers) and it is possible that turtles may have dispersed from these sites to Jerry Sulina Park. Its current absence also suggests it may have continued to move throughout the expansive aquatic habitat available to it and could be in many locations within the watershed or beyond.
Methods
Habitat and Threat Assessments Based on information synthesized by Semproni and Ogilvie 2, Engelstoft and Ovaska 3, and through a literature search on Western Painted Turtle habitat needs and associated threats, the following information on habitat features and threats to known (or potential) turtle habitat and populations was collected: • Landscape context: urban, rural, agricultural, and back-country • Landscape type: coniferous, deciduous, mix-forest, urban • Wetland type: marsh, natural pond, river, stream, man-made pond, lake • Bottom substrate: silt/mud, detritus/organics/muck, sand/gravel, bed-rock, wood • Percentage cover of emergent, submergent, and floating-leaved aquatic plants (categories for cover: <5%, 5-50%, 51-95% and >95%) and dominant plant species where possible • Percentage cover of forest, shrub, grass/herb, and developed areas along the riparian edge (categories for cover: <5%, 5-50%, 51-95% and >95%) • Availability of basking logs (none, not enough, sufficient) • Availability of nesting grounds (none, not enough, sufficient, unknown) • A site description overview • Whether or not turtles were seen during the site visit, and a list of other fish/wildlife species observed • An overview of threats to breeding grounds • Potential threats to turtles and associated habitat (aquatic and within 350 m of water’s edge) and level of threat (low, medium, and high): roads (paved and unpaved), residential, recreation (motorized and non-motorized), agriculture, pets, grazing, exotic species and other threats (usually collection and pollution)
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Surveying Basking surveys were conducted using visual searches of basking turtles (Western Painted Turtles, introduced Red-eared Sliders and other species) hauled out on logs, rocks, or shoreline areas in water bodies using binoculars and/or a spotting scope. Surveys were conducted at this site either by foot from vantage points on the shore or by kayak. All surveys were conducted between 9:00 am and 3:00 pm on warm, sunny days of zero precipitation early in the season when turtles were mostly likely to be basking 4. The following information was recorded: • Date and start/end time of the surveys to calculate search effort • Survey method (by foot or kayak) • Wind speed (various categories from Calm to Strong) • Air temperature • Percentage cloud cover • Precipitation (various categories from None to Snow). • Number of individual turtles observed • Species • Exact location of the observation (GPS coordinates: 10 U, NAD83 datum using a Garmin GPSmap 60Cx) • The activity in which the turtle was engaged (basking, swimming, nesting, etc.) • The habitat feature with which it was associated (basking log, shoreline, open water, etc.) • The size class and sex of the turtle (if known) For ease in the field, a GPS Waypoint Naming Convention was created that allowed the entry of all of this data as one Waypoint name into the GPS unit. Photographs of turtles were taken whenever possible.
Nesting surveys at this site were conducted in the late afternoons and evenings in May through June. Surveys were conducted in suitable upland habitat within 150 m from the edge of the water body based on the following criteria known from the literature 5,6,7,8 • Exposed sandy soil with little or no vegetation • South-facing aspect • Flat or gentle slope • Limited understory and canopy cover • Within 150 m from the water’s edge
We searched for both nesting turtles and evidence of nesting, which is usually visible in the form of test holes, depredated and emerged nest holes, and egg shell remains from predation 3. The following information was recorded: • Survey location (description and GPS coordinates) • Date and start/end time of the survey • Species of turtle observed • Notch code (for turtles already marked on the Sunshine Coast) • Nesting substrate used • Distance from the water • Number of eggs laid
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Landscape Mapping The landscape features we mapped were based on habitat analyses conducted by Marchand and Litvaitis 9. Habitat features were digitized using ArcGIS 10 and the bc_gvrd_west_xc200mm_utm10_2009 orthophotography layer, located on the BC Integrated Land Management Bureau’s GeoBC web map server, as well as personal knowledge from site visits. Habitat was also digitized using Google Earth imagery (2008), which was then converted into an ArcGIS shapefile. Area in hectares and perimeter in meters were then calculated for each habitat type within each buffer zone using the Intersect Tool. Habitat definitions (Table 1) were descriptions of different habitats encountered throughout the study area.
Table 1: Habitat definitions used for analysis of habitat composition in 50, 200, and 350 m buffer zones around the primary aquatic habitat.
Habitat Type Description
Aquatic Habitat Primary aquatic habitat. Water bodies known to contain WPT, and/or connected immediately adjacent waterbodies suitable for WPT
Potential Nesting Habitat Areas that WPT may use for nesting. Has somewhat suitable substrate, aspect, and cover
Known Nesting Habitat Nests, or nesting turtles have been observed in this habitat
Additional Aquatic Habitat Additional aquatic habitat that may be suitable for WPT, but have no confirmed occurrences
Wetland Terrestrial wetland habitat. May include marsh, fen, fen, bog and swamp
Stream Small streams. Low suitability as permanent habitat but may be used as movement corridors for WPT
River Large, moderate to fast flowing streams. Low suitability as permanent habitat for WPT, but may be used as movement corridors
Mixed Grass Naturalized or maintained grassy areas. Includes set-asides, oldfield habitat, dunegrass habitat, and lawns
Shrubs Shrubby species less than 3 m high. May include mixed riparian areas
Mixed Forest Mixed forest of both deciduous and coniferous species
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Coniferous Forest Forest primarily composed of coniferous species
Deciduous Forest Forest primarily composed of deciduous species
Rock Exposed bedrock
Development Developed areas, including residential, commercial and industrial buildings. May contain large areas of lawn and some trees, but not naturalized. At Iona Beach Regional Park this includes waste water treatment ponds
Agriculture Agricultural land. May include crops, small outbuildings, fallow fields
Gravel Path Gravel, sand or dirt paths used primarily for foot or bicycle traffic
Paved Path Paved path used primarily for foot or bicycle traffic
Gravel Road Gravel roads and parking lots used primarily for vehicle traffic
Paved Road Paved roads and parking lots used primarily for vehicle traffic
Railroad Railroads
Marine Marine and estuarine environments
Results
Landscape Composition This site is riverine habitat, surrounded by current and former agricultural lands. Vegetation is dominated by grass species with stands of deciduous shrubs and trees. The immediately adjacent areas are reclaimed land that is quite naturalized, though there are many footpaths throughout the site. Large flood prevention dykes surround the site on one side, and it is bound by the mainstem of the South Alouette River on the other. There is a parking lot and busy road within the first and second buffer zone, and some rural housing as well. The outer buffer zones are dominated
- 5 - by agricultural land used for blueberry and hay (Table 2). There are several areas of aquatic habitat within 350 m of the site that are apparently not currently being used by this small population of turtles.
Potentially suitable nesting habitat (PNH) is currently limited to two small gravel/sand beaches that are heavily impacted by park users and dog owners using the off-leash area (Fig. 2 and 3). As well, there are several gravel pathways that may be attracting nesting turtles, although these pathways are even more heavily impacted and compact than the beach sites.
Table 2. Landscape level habitat composition
Area Percentage of Buffer (ha) Zone Open Water Habitat 15.20 50 m Buffer Zone 7.91 Gravel Paths 0.65 8.3 Paved Roads 0.04 0.5 Development 0.42 5.3 Upland Habitat - Landscape features in 50 m Agriculture 0.21 2.6 buffer zone River 0.56 7.1 Other Aquatic Habitat 0.02 0.3 Naturalized Riparian Habitat 6.01 76.0 200 m Buffer Zone 30.12 Gravel Paths 0.70 2.3 Paved Roads 0.31 1.0 Development 4.03 13.4 Upland Habitat - Landscape features in 200 m Agriculture 13.37 44.4 buffer zone River 1.93 6.4 Other Aquatic Habitat 0.76 2.5 Naturalized Riparian Habitat 9.01 29.9 350 m Buffer Zone 43.44 Gravel Paths 0.52 1.2 Paved Roads 0.26 0.6 Development 2.64 6.1 Upland Habitat - Landscape features in 350 m Agriculture 29.74 68.5 buffer zone River 1.48 3.4 Other Aquatic Habitat 1.13 2.6 Naturalized Riparian Habitat 7.69 17.7 Nesting area within buffer zones - PNH1 0.01
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Figure 2. Western Painted Turtle habitat and associated upland buffer zones. - 7 -
Figure 3 . Zoomed view of turtle habitat at Jerry Sulina Park, including Potential nesting habitat. - 8 -
Monitoring Six occurrence surveys for a total of 6.5 Search Effort Hours were conducted at Jerry Sulina Park, in which only invasive turtles were observed, including a maximum of 16 Red-eared Sliders and 1 Easter River Cooter (Table 3.). Nesting surveys at this site have not resulted in any observations.
Table 1. Occurrence surveys conducted at Jerry Sulina Municipal Park from 2009 to 2011.
Search Survey Effort WPT Location (UTM Other Location (UTM Year # Date Hours (# Ind.) - 10 U) Comment Turtles Species - 10 U) Comment
526435 1 Red-eared Slider Basking on log 5454409 526477 1 31-May 1 0 N/A N/A 2 Red-eared Slider Basking on log 5454421 2009 526529 1 Red-eared Slider Basking on log 5454438 526458 2 31-Jul 1.5 0 N/A N/A 1 Red-eared Slider Basking on log 5454422 526508 1 14-Apr 1.25 0 N/A N/A 6 Red-eared Slider Basking on logs 5454428 526508 2010 9 Red-eared Slider Basking on log 5454428 2 16-Apr 0.5 0 N/A N/A 526508 2 Unknownn Turtle Basking on log 5454428 526479 10 Red-eared Slider 9 basking on log, 1 swimming 5454422 1 13-May 1.25 0 NA NA 526351 6 Red-eared Slider 6 basking on log 2011 5454458 5 Red-eared Slider 526461 2 31-May 1 0 N/A N/A 6 1 Eastern River Basking on log 5454417 Cooter
Threats Although the population of Western Painted Turtles at this site may or may not be natural or viable in the long term due to the limited number of individuals, it is nonetheless a population of a provincially Red-listed species and the site-level threats must be assessed.
Development of the area is not a concern in the near future, as the site is located within a municipal park. However there are several other serious threats to survival and recruitment that will likely need to be addressed in order for this population to persist.
1. Disturbance of nesting female turtles by humans and dogs: Western painted turtle females will come on land to nest during late spring to early summer, generally laying one clutch of 6 to 23 eggs in sandy, gently sloping substrate within 150 m of the shore 6. The process of digging a nest, laying eggs, and then burying the nest takes approximately an hour, during which time females are susceptible to higher levels of predation than would be the case when in water. Female turtles are therefore quite skittish during this process and are easily deterred from completing a nesting attempt by the presence of humans or
- 9 - dogs in close proximity to the nest site. The potential for human and dog disturbance of nesting turtles is quite high at Jerry Sulina, as the largest amount of suitable nesting area is a designated dog beach. During one site visit, a park visitor reported seeing a dog with a turtle in its mouth during a previous visit.
2. Nest disturbance by dogs and human-subsidized predators: In areas impacted by human activity, rates of egg and hatchling predation are increased substantially through nest disturbance by dogs and increased predation rates by subsidized predators (e.g., raccoons, coyotes, crows, etc.) 7. Off-leash dogs have been known to dig up newly laid turtle nests, destroying the eggs. Subsidized predators may be attracted to nesting sites by garbage, increasing the likelihood of nest predation.
3. Collection and movement of turtles: The collection of Western Painted Turtles as pets and movement of turtles between sites by humans constitutes a major threat to population viability via direct removal of individuals from the population and/or relocation to potentially unsuitable sites 10 . Anecdotal evidence suggests that collection and movement of Western Painted Turtles is a major problem on the south coast of B.C. 11
4. Road mortality: Western painted turtles will occasionally travel overland for considerable distances (up to 3 km) in search of suitable nesting habitat (late spring-early summer) or to transition between wintering and breeding habitat 12 . Such movements may result in a high risk of road mortality. Given the location of Jerry Sulina Park in a rural agricultural area, the risk of road mortality at this site is considerably less than at more urbanized turtle-occupied sites. However, 201st Street is within 50 m of the water’s edge, as is the park parking lot, suggesting a potential for vehicle-related mortality of turtles at this site.
5. Introduced Species: Several Red-eared Sliders ( Trachemys scripta elegans ), an exotic turtle species whose presence in the area is the result of pet release, have been observed at Jerry Sulina Park. Release of pet turtles may be ongoing and results from a lack of information by the public that this practice has a potential negative impact on native fauna. Red-eared Sliders are known to compete with the native turtles for resources such as food and, perhaps more importantly, basking space 13 . Sliders are generally larger than Painted Turtles and can easily displace them from prime basking areas. In addition to introduced turtle species, introduced frogs (e.g., Bullfrogs) and fish (e.g., Largemouth Bass) species that cohabit the Jerry Sulina wetland may pose a direct predation threat to hatchlings and juvenile turtles if successful nesting occurs 14 .
Several invasive species of upland and aquatic vegetation are also present at this site including Japanese Knotweed ( Polygonum cuspidatum ) and Asian Water Lily ( Nymphaea odorata ). These
- 10 - aggressive species may quickly overgrow potential nesting areas, cause egg damage due to their aggressive root structures 15 , and also cause changes to Western Painted Turtles’ foraging and basking behavior of if movement is restricted 6.
6. Limited basking habitat: As mentioned above and illustrated in Figure 2, all available basking habitat is located along the banks of the slough. The amount of basking area is limited, leading to potential competition for space between Western Painted Turtles and Red-eared Sliders 13 . Furthermore, the location of these habitat features (i.e., directly against the shoreline) is less than ideal as turtles prefer to bask in deeper water away from the shore, facilitating underwater escape and decreasing vulnerability to terrestrial predators 13 .
7. Human disturbance of basking turtles This site is a popular location for recreation, including cycling, horseback riding, and walking. There are numerous trails immediately adjacent to aquatic areas occupied by turtles, and this disturbance may be detrimental if basking turtles are repeatedly disturbed, which may limit their ability to properly thermoregulate 13 .
8. Natural system modifications The site is located immediately adjacent to dykes used for flood prevention. In order to ensure these structures remain in good working order, the municipality periodically modifies the bank habitat by cutting vegetation on the sides of the dykes. This mowing may negatively impact turtles, particularly if females are hit by the mower when searching for nesting habitat. This type of impact is likely if nesting turtles are attracted to the gravel pathways on the top of the dyke, as previously mentioned. If nesting in this area was occurring there would also be a potential for hatchlings to be killed while making their way from nest sites to the water. As well the high level of use has contributed to heavy erosion in some areas, particularly in potential nesting areas.
Management recommendations There is a substantial opportunity for collaboration and partnership with the municipality of Maple Ridge in protecting and enhancing the population of Western Painted Turtles at this site. As the landowners and managers of the park, any and all protection and restoration efforts would necessarily go through their staff.
Monitoring Although there have been several site surveys completed at the site, a continued effort is essential to confirm the presence of Western Painted Turtles at this site, as well as identification of essential habitat features and population structure. A survey plan for the entire Alouette watershed has been drafted as part of the BC Hydro’s Fish and Wildlife Compensation Alouette Watershed Species at Risk Project, and surveys already begun in 2011 continue in 2012.
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Interpretive Signage The South Coast Western Painted Turtle Recovery Project would like to produce and install a permanent interpretive sign describing the Western Painted Turtle, the threats it faces, and actions that community members can take to help in the recovery of this species. Examples of two existing sign designs are shown below (Figs. 3 and 4), and the designs can be edited to meet the requirements of the individual park. Working with park managers to determine the best placement for the sign is also recommended. The sign will serve to educate park patrons about the existence of this Endangered turtle species in their community, a simple and straightforward way to address several of the threats listed above (namely threats 1, 3, 4, and 5). Indeed our group has found that many BC south coast residents are unaware that a native turtle species exists in BC. This lack of information presumably contributes directly to several threats, including disturbance of nesting turtles, release of exotic pets, and turtle collection/movement.
Figure 4. Possible interpretive signage for Jerry Sulina Park –Option 1
- 12 -
Figure 5. Possible interpretive signage for Jerry Sulina Park - Option 2
Nest Site Enhancement As noted above, the designated dog beach provides the largest area of suitable nesting habitat at this park. However, rather than altering this park feature in any way, we propose an enhancement of the small gravel beach to the west of the dog beach (Fig. 2). This would serve to offer an attractive nest site alternative to gravid female turtles, and would reduce disturbance of nesting females and nest destruction by dogs and wildlife. This enhancement work would consist of:
1. Adding additional substrate (composed of sand and loam, the preferred nesting substrate for painted turtles) 16 to the target area and smoothing the slope to approximately 45 o. 2. Adding a small fence between the nesting area and the walking path immediately adjacent to it. 3. Installing a small sign describing the purpose of the nesting area and requesting that park patrons and their dogs keep off.
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This work could feasibly be completed in one day and would be effective against threats 1 and 2 above. The fence and sign will prevent the public and their pets from directly interfering with nesting females and disturbing nests. The addition of substrate will produce an attractive alternative to the dog beach. The sign and fence should also reduce the accumulation of any garbage near the nest site (reducing visitation by subsidized predators), and the fence may directly deter larger nest predators such as coyotes.
Installation of Basking Logs To increase basking habitat available to Western Painted Turtles, we propose installing additional basking logs in the open pond area. Logs would be brought to the site by truck and anchored in position, either by attaching them to objects on the shoreline or by chain to an anchor on the pond bottom. This work could be completed in one day and would address threats 5, 6, and 7 above.
References 1District of Maple Ridge, 2012. Jerry Sulina Park: Dog Off-leash area. http://www.pittmeadows.bc.ca/assets/Parks/pdfs/sulina%20off%20leash%20park.pdf
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12 Bowne, D.R., M.A. Bowers, and J.E. Hines. 2006. Connectivity in an agricultural landscape as reflected by interpond movements of a freshwater turtle. Conserv. Biol. 20(3) 780-791. 13 Cadi, A. and P. Joly. 2003. Competition for basking places between the endangered European pond turtle ( Emys orbicularis galloitalica ) and the introduced Red-eared slider ( Trachemys scripta elegans ). Can. J. Zool. 81:1392-1398. 14 Hays, D.W., K.R. McAllister, S.A. Richardson, and D.W. Stinson. 1999. Washington state recovery plan for the Western Pond Turtle. W.A. Dept. Fish and Wildl. Olympia, WA. 15 Maltby, F. L. 2000. Painted turtle nest site enhancement and monitoring, Red Devil Hill nest site at Revelstoke, BC. Prepared for the Columbia Basin Fish and Wildlife Compensation Program, Nelson, BC. 16 Costanzo, J.P., J.D. Litzgus, J.L. Larson, J.B. Iverson, and R.E. Lee, Jr. 2000b. Characteristics of nest soil, but not geographic origin, influence cold hardiness of hatchling Painted Turtles. J. Therm. Biol. 26:65-73.
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Appendix II: Survey Site Codes
SITE NAME CODE
001 Lower Alouette
Pitt River Marina Sloughs and 002 Ponds
Northwest Harris Rd. Private 003 Ponds
Northeast Harris Rd. Private 004 Ponds
North Richardson Rd. Private 005 Pond A
North Richardson Rd. Private 006 Pond B
007 McNeil Rd. Sloughs
008 West McNeil Rd. Private Pond
009 Menzies Rd. Private Pond
010 North McNeil Rd. Private Pond
011 North Alouette Ponds
011 North Alouette
012 North Alouette Environs
012 North Alouette Environs
East Neaves Rd. Ponds and 013 Sloughs
014 Blaney Creek and Environs
014 Blaney Creek and Environs
015 Codd Wetland
Southeast Neaves Rd. Private 016 Pond
016 Alouette Irrigation Ditches
Aquilini Cranberry Irrigation 018 Ditches
South Alouette Downstream of 019 Jerry Sulina
020 Jerry Sulina Park and environs
South Alouette Upstream Jerry 020 Sulinas and Upstream
021 Heron Colony Wetland
022 West 216th St Private Pond A
023 West 216th St. Private Pond B
024 East 2224th St Private Pond
South Alouette Slough at 232nd 025 St.
026 North 124th Ave Private Pond
027 Fern Crescent Private Wetland
028 South Justice Institute Pond
029 North Justice Institute Ponds
030 North
031 North 256th St. Pond A
032 North 256th St. Pond B
033 Golden Pond
034 Mike Lake
035 Mirror Lake
036 Marc Rd. Wetland
037 Cranberry Lake
038 Blaney Lake
039 Loon Lake
040 Jacobs/Marion Lake 041 Goose Lake 10
Appendix III: Survey Site Data Sheet OTHER PERIMETER FIRST SECOND THIRD MAX # TURTLE BULLFROGS SITE (m) / LENGTH HABITAT START OCC. GREEN OTHER HAB. OBS. AREA2 ) TYPE OBS. UTM'S END UTM'S SURVEY SURVEY SURVEY (Y/N) WPT SPECIES OTHER CONTACT SHEET COMMENTS CODE (m) (when (m DATE DATE DATE OBS PRESEN FROGS INVASIVES SAR INFO SHEET (Y/N) followed by T (Y/N) (Y/N) N/A in AREA) (Y/N) 001 3427 N/A
002 831 4814
003 611 7615
004 345 5032
005 130 994
006 300 3801
007 1772 N/A
008 378 2551
009 245 1100
010 476 5500
011 491 3467
011 9664 N/A
012 1640 23484
012 847 N/A
013 2077 19283
014 1195 13596
014 9900 N/A
015 2012 220322
016 238 2881
016 22256 N/A
018 6691 N/A
019 5270 N/A
020 2626 18768
020 3531 N/A
021 529 4256
022 384 3970
023 363 3010
024 108 837
025 632 3983
026 217 2445 11
027 829 5250
028 148 1025
029 761 7937
030 436 9143
031 333 6362
032 397 2883
033 913 13234
034 1812 98368
035 493 14785
036 108 791
037 905 18859
038 2962 136766
039 5713 541872
040 3058 204308
041 Needs to be delineated in GIS Appendix IV: Turtle Occurrence Survey Data Collection Form Turtle Occurrence Survey Data – Occurrence Information % Site used by turtles: Site Name: ______Survey # _____ Site ID#: ______Date ______Start: ______End: ______
Survey Canoe/ Wind: Calm Light air Light breeze Precipitation: None Fog Temp (C°): Air Method: Land Power Boat Cloud Cover: Clear Gentle breeze Moderate Fresh Mist Drizzle Light Hard Kayak <50% >50% 100% Strong Snow
Species Activity Habitat Feature Obs. # Time # Ind. (Code) WYPT ID: Easting Northing Error (Code) (Code) Size Class Sex
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Appendix V: Habitat and Threat Assessment Data Collection Form
General Site Survey Site Name: Survey # Site ID#: Elevation: Area (ha): % Site used by turtles: Cloud Cover: Clear Wind: Calm Light air Light breeze Gentle breeze Precipitation: None Fog Mist Drizzle Temp (C°): Air: Water: <50% >50% 100% Moderate Fresh Strong Light Hard Snow Power Date: Survey Start: Survey End: Survey Method: Land/ By Foot Canoe/ Kayak Boat Easting: Site GPS Information: Location: WYPT ID: ______Northing: ______Error:______Landscape context Urban Rural Agricultural Back-country Other Landscape type: Coniferous Deciduous Mix-forest Urban Other Type: Marsh Natural Pond River Stream Man-made Pond Lake Other: ______Substrate: Silt/mud Detritus/organics/muck Sand/gravel Other (Bed-rock, wood) Aquatic vegetation cover: ____% emergent ____% submergent ____% floating -leaved ____% invasives ______Dominant plant species: ______Perimeter cover: ___% Forest ____% Shrub ____%Grass/Herb ___% Developed ____% Other: ______(Categories for Cover: A: <5; B: 5 -50; C: 51 -95; D: >95 ) Site description: Basking Logs None Not enough Sufficient Nesting grounds None Not enough Sufficient Unknown Evidence of Breeding? No Yes Threats to breeding grounds Roads (paved) Roads (unpaved) Residential High Other urban High Recreation (motorized) Agriculture High Med Logging High Med High Med Low High Med Low Med Low n/a Med Low n/a High Med Low n/a Low n/a Low n/a Threats (aquatic and within n/a n/a 350 m of water's edge) Recreation (non motorized) High Med Exotic species High Med Low n/a (Species): Pets High Med Grazing High Other: ______Low n/a (Type): ______Low n/a Med Low n/a ______
Further notes on threats
Turtles seen? Yes No Western Painted Turtle? Yes No Other Wildlife:
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Appendix V: Survey Overview Maps
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15
16
17
18
19
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