An Examination of the Western Pond Turtle (Actinemys. marmorata), to Improve Monitoring and Habitat. Conservation

Transcription

1 An Examination of the Western Pond Turtle (Actinemys marmorata), to Improve Monitoring and Habitat Conservation Ryan Patrick Shaw ENVS 190; Senior Thesis California State University, Sacramento December 15, 2016

2 Table of Contents: Abstract...pg. 2 Introduction.. pg.2 Background....pg.2 Range and Description.. pg.3 Area of Focus pg.5 Biology.pg.5 Habitat.pg.7 Stressors..pg.8 Resiliency.pg.9 Status.pg.10 Methods pg.10 Sampling and Monitoring pg.11 Results pg.14 Visual Encounter Surveys.pg.14 Trapping pg.14 Discussion pg.16 Monitoring and Conservation pg.16 Conclusion pg.18 Figures pg.20 Literature Cited pg.23 1

3 Abstract The Western Pond Turtle (Actinemys marmorata), California s only native freshwater turtle species, has seen significant population declines resulting mostly from habitat loss. In this report, an in-depth examination of the western pond turtle was conducted as well as an assessment of various sampling techniques and monitoring strategies, to improve conservation and restoration efforts. While the Western Pond Turtle has yet to gain federal status as an endangered species, the states of Washington, Oregon, and California have designated the western pond turtle as either endangered or as a species of special concern under state laws. While there is, limited information published on the wester pond turtle; it is the goal of this study to provide information in hopes of improving monitoring, management, and conservation strategies, to increase population distributions as well as improve survival rates. Introduction Background Western Pond Turtle (WPT) populations thrived in freshwater systems along the west coast long before the arrival of a European settlers (Bushell and Geist, 2012). Most of California s marshes, wetlands, lakes, and ponds provided refuge to the WPT, which had populations estimated in the millions (Bushell and Geist, 2012). As populations of European settlers began to increase, cities and areas of urbanization exploded causing a dramatic surge in the turtle harvesting industry. Commercial turtle harvesting, which peaked in the late 1800 s, led to the slaughter of more than ten thousand Western Pond Turtles, dramatically reducing populations across the state (Bushell and Geist, 2012). Additionally, as part of a fast-growing 2

4 human population, came higher demands for water resources, mostly in the form of irrigation to sustain a flourishing agricultural industry, which proceeded to the draining of critical turtle habitats (Bushell and Geist, 2012). The Western Pond Turtle is still facing many of the same adversities it saw over a century ago. Drought conditions have led to population declines throughout its distribution mainly from increased anthropogenic water needs, increased urbanization, and agricultural water exploitation which continues to create fragmented WPT populations. The introduction of exotic species, such as the Red Eared Slider (Trachemys scripta elegans), has also been an important factor which has further exacerbated the levels of strain placed upon this turtle species, affecting its push for survival (Bushell and Geist, 2012). Range and Description The Wester Pond Turtle, also known as the Pacific Pond Turtle, is California and southern Oregon s only native fresh water turtle species, ranging (Figure 1) along the Pacific coast of North America from Washington south to Northern Baja California (Germano and Rathbun, 2008; Rathbun, et al., 2002). There are records of the Western Pond Turtle inhabiting parts of eastern Oregon as well as isolated incidences of populations found in the Truckee and Carson Rivers located in western Nevada (Bury, et al., 2012a). Much of the Western Pond Turtle s populations, however, are found within the state of California, west of the Cascade and Sierra Nevada Mountain ranges, where it benefits from a Mediterranean climate distinguished by long, warm, dry summers, and short, mild, wet winters (Rathbun, et al., 2002). In Washington, Western Pond Turtle populations have been virtually eradicated from historic habitat, while the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) recently listed the turtle as a Canadian Species at Risk (Giese, et al., 2012). The Western Pond 3

5 Turtle is semiaquatic, meaning that spends its lifetime in both aquatic and terrestrial microhabitats (Bury, et al., 2012a). The Western Pond Turtle is described as a small to medium sized aquatic turtle (Bury, et al., 2012a). It can grow up to 241 mm in length and can reach a maximum weight of 1,200 g. On average, however, many adults measure between 160 mm to 180 mm long and weigh 500 g to 700 g (Bury, et al., 2012a). The coloration and markings found on these turtles can widely vary based on geography, ontogeny (developmental history), and sex (Bury, et al., 2012a). In most cases, however, turtles are olive to dark brown dorsally, with many exhibiting darker reticulations (dots or streaks) (Bury, et al., 2012a). Western Pond Turtles utilize this cryptic coloration pattern as these dorsal colors are made to resemble rocks, like the ones found in lakes and ponds (Bury, et al., 2012a). Coloration on the underside of this species can be yellowish, occasionally with dark blotches found near the center of the hardened scutes. Males tend to have yellow or whitish chin and throat color patterns, while female species (Figure 2) are more lighter shades of brown containing darker spots. While there is some degree of color dimorphism, is has been shown to be less pronounced or even absent in southern California sub-species, although these characteristics have not been well researched (Bury, et al., 2012a). Apart from the WPT sub-species inhabiting southern Calidornia, many of these turtles do exhibit sexual dimorphism at maturity, usually observable when carapace lengths measure roughly 125 mm (Bury, et al., 2012a). Until then, juveniles of both sexes often display coloration and markings of females (Bury, et al., 2012a). 4

6 Area of Focus This project will provide an evaluation of methods and techniques used in the sampling and monitoring of the western pond turtle. As part of a thorough examination of the species, this evaluation will also assess the biology, habitat, stressors, status and resiliency for the purposes of improving and maintaining conservation and restoration practices. Biology The WPT is omnivorous establishing itself as an opportunistic feeder (Bury et al., 2012b). Showing preferences for adult and larval insects, crustaceans, and various annelids, plant matter makes up a significant portion of the diet as well (Bury, et al., 2012b). Although most of their diet is comprised of small aquatic invertebrates, occasionally they have been shown to consume small vertebrates such as fish, frogs, and tadpoles (Bury, et al., 2012b). This species spends most the day searching for food, utilizing its highly-developed sense of sight and smell (Bury et al., 2012c). The western pond turtle spends varying parts of the day basking in the sun as a primary way of increasing and maintaining body temperature (thermoregulation). During these times, the WPT is most visible, as they position and expose themselves upon logs, rocks, or shorelines (Bury, et al., 2012b). Typically, the WPT will participate in aerial basking when water temperatures become lower than surrounding air temperatures (Jennings and Hayes, 1994). How often this species basks in a day depends on multiple factors acting together, such as ambient air temperature, water temperature, and body size (Bury, et al., 2012b). On average, however, during spring and summer months, turtles have been recorded as spending between 5

7 2 and 4 hours basking per day. The WPT is also capable of aquatic basking (e.g., floating in upper thermal layers found in algal mats), where they can remain undetected (Bury, et al., 2012b). Furthermore, basking in exposed areas out of the water can occur with less frequency in warmer areas. For instance, in California s Central Valley, the amalgamation of warm air temperatures common during summer months and shallow-water habitats, increases water temperatures for extensive periods of the year (Bury, et al., 2012b). Conversely, opposite of basking to increase body temperatures, the WPT also has been shown to aestivate, (enter a state of dormancy comparable to that of hibernation, defined by inactivity to lower metabolic rates in response to high temperature extremes and arid conditions), to maintain its physiological functions (Jennings and Hayes, 1994). Many WPT populations overwinter by burying themselves in leaf litter or other terrestrial substrates (Bury, et al., 2012b). This process usually begins in September or October and ends in the spring typically in March through April (Bury, et al., 2012b). In Central California, adult turtles leave aquatic and riparian habitats and move upland into terrestrial areas varying with microhabitat structures with distances measuring 500 meters or more for 110 days on average (Bury, et al., 2012b; Reese and Welsh 1997). Bury et al (2012b) and Giese et al (2012), both agree that sexual maturity is reached in females between seven and eleven years of age, however, reproductive maturity can also be established based on carapace length, which is concluded as being roughly mm (Bury et al., 2012b; Giese et al., 2012). It is largely unknown when males become sexually mature, although males begin to show external signs of dimorphism when carapace length reaches mm (Bury, et al., 2012b). Courtship and mating occurs predominantly during the spring, 6

8 however can ensue throughout most of the year except between December and January (Bury et al., 2012b). Nesting typically takes place anywhere from April through August, with the majority taking place from late May to early July (Giese, et al., 2012). Females will travel rather extensively to find suitable nest sites in terrestrial habitats, with distances being recorded as far as 400 meters (Ernst et al., 1994). When appropriate nesting sites are found, the female will evacuate her bladder to loosen soils for easier digging, creating a flask shaped hole measuring roughly seven cm deep (Bury, et al., 2012b). The female WPT will typically produce one to two clutches per year, with clutch sizes ranging from one to twelve eggs, usually depending on female carapace length (Ernst et al., 1994). Incubation periods last approximately three months, while hatchling survival rates during the first year are estimated at just fifteen percent (Reese, 1996). Habitat The WPT is a species that requires aquatic and terrestrial habitats. Within its range, the WPT has been found to inhabit riparian habitats with populations occurring in ponds, marshes, streams, rivers, lakes, vernal pools, and reservoirs (Bury, et al., 2012b; Giese, et al., 2012). Common features of turtle habitat include slow moving deep waters, abundant vegetation, as well as available aerial basking sites (Jennings and Hayes, 1994). Hatchlings necessitate shallow water habitats with plenty of vegetation in which to forage (Jennings and Hayes, 1994). Aside from providing as a nutritional resource, aquatic vegetation also serves as refuge from predators and heat (Ernst et al., 1994). While aquatic habitats are vital for this species, adjacent terrestrial habitats are just as important (Giese, et al., 2012). Terrestrial habitats are used for migration, overwintering, aestivation, and nesting (Giese, et al., 2012). 7

9 Stressors As a significant component of aquatic ecosystems, freshwater turtles are vital due to their abundance, large biomass, and longevity (Bury, 2011). Unable to endure significant losses and still maintain population levels due to slow rates of maturation and reproduction, the western pond turtle is threatened with the ability to maintain its persistence (Bury, 2011). Anthropogenic influences, combined with various environmental events have led to population declines as well as overall decreases in population distributions. However, habitat loss, fragmentation, and alteration, are main reasons for declines in WPT populations (Giese, et al., 2012). Within California, distributions have become limited, as 15-20% of their range has been reduced as well as most of their remaining habitat being greatly fragmented (Reese, 1996). Furthermore, roughly 90% of Central Valley grasslands, riparian habitats, old growth forests, and wetlands within the state of California no longer exist due to increased farmland and urbanization placing many species, like the WPT and many others at risk (Soule, 1995). The introduction of exotic pest species, also referred to as invasive or introduced species, has also contributed to population declines of the WPT. Invasive species affect the survival of the WPT through predation, exposure to disease, and direct competition (Giese, et al., 2012). Furthermore, studies have indicated that other factors such as habitat modification, chemical contaminants, and disease, can increase the negative effects of invasive species (Giese, et al., 2012). As an indirect effect of urbanization, invasive species are shown to be more common in urban areas resulting from human releases (Giese, et al., 2012). Among the most noteworthy invasive species to affect the health of western pond turtle, are the red-eared 8

10 slider (Trachemys scripta elegans), bullfrog (Rana catesbeiana), and bass (Micropterus spp.) (Thomson, et al., 2010; Giese, et al., 2012). Resulting from widespread introductions from both the pet and food industries, the redeared slider is the leading invasive reptile species in the world (Thomson, et al., 2010). This invasive turtle species has been shown to outcompete western pond turtles for habitat and food resources as they are significantly larger and can reproduce at faster rates (Thomson, et al., 2010). The Bullfrog, native to eastern North America has successfully established itself in all lower 48 states including California (Giese, et al., 2012). A bullfrog will prey upon any live animal they can swallow, including young western pond turtles and hatchlings (Giese, et al., 2012). It is also worth noting that bullfrogs in their larval stage can act as predators against the WPT (Giese, et al., 2012). Additionally, bass have been reported to prey on the WPT, however small juveniles are mostly targeted (Giese, et al., 2012). Resiliency Despite the many hardships facing western pond turtle populations, they have shown great resiliency in their survival. One unique mechanism utilized by the WPT is the ability of females to initiate a preoviposition arrest (a mechanism that allows females to retain their eggs), when conditions are less desirable or when faced by different threats (Reese and Welsh, 1997). The WPT is benefitted by its ability to survive durations of low or limited recruitment directly attributed to its longevity (Germano and Bury, 2001). The turtle species is considered to be a habitat generalist, meaning that it can survive in a wide range of combined terrestrial and aquatic habitats (Reese and Welsh, 1997). Additionally, the Western Pond Turtle can increase 9

11 its chances of survival through its dietary habits. Being omnivorous, these turtles can take advantage of vegetative food resources in the absence of its carnivorous preferences and vice versa (Giese, et al., 2012). Status As well as being significantly threatened within the state of California, recent studies have found the WPT to be seriously threatened in most of its range outside of the golden state (Jennings and Hayes, 1994). Regardless of its ability to make use of a wide range of habitat, populations are in decline (Reese and Welsh, 1997). In 1992, the WPT was petitioned for listing under the Federal Endangered Species Act; however, following an official review, United States Fish and Wildlife Service (USFWS) concluded that listing the Western Pond Turtle as threatened or endangered was not justified at this time (Bury, et al., 2012a). Within the state of California, the WPT has been delegated as a Species of Special Concern. Furthermore, the state of Washington listed the WPT as an endangered species and the state of Oregon has the WPT listed as Sensitive-Critical (Bury, et al., 2012a). Methods The information provided in this report was collected through extensive library research. Discussed in this section are the methods used in researched reports for the collection of data surrounding the WPT. The methods that will be expanded upon include visual encounter surveys (VES) as well as three trapping designs including: muddling, commercial collapsible traps, and fyke traps. 10

12 Sampling and Monitoring Visual Encounter Surveying Visual encounter surveys (VES) allow for quick evaluations of species within a study area (Bury, et al., 2012c). VES s are based on consistent timed periods in which quick assessments of species occurrence (found/not found) and population counts can be measured (Bury, et al., 2012c). In addition, while conducting visual surveys, the use of binoculars or spotting scopes may be used for more effective measuring (Bury, et al., 2012c). In a study conducted by Germano and Bury (2001) to determine status and population structure, visual surveys were conducted throughout 55 sites in the Central Valley of California. 10 X 50 binoculars were used for scanning potential basking sites within turtle habitats for the presence of the WPT (Germano and Bury 2001). Individuals observed were recorded and separated by size classifications (small, medium, large) (Germano and Bury 2001). VES surveying was also used to determine preferred or potential habitat through the visual assessment of vegetation and in locating basking sites (Germano and Bury 2001). In a separate study, conducted by Burbrink, et al., (1998), VES surveying techniques were used to tract the movement of reptiles and amphibian species in a riparian zone located in southern Illinois to determine a dispersal corridor. To determine the numbers of reptile and amphibian species present within the study zone, daylight visual encounter surveys were conducted within a 500 meter transect by turning ground cover, inspecting retreats, and watching for surface activity (Burbrink, et al., 1998). 11

13 Trapping It is critical to remember that a State scientific collection or study permit is needed and required when collecting the WPT in all states where they naturally exist (note: additional permits may be required from federal agencies) (Bury, et al., 2012d). Permits are required for field sampling (Bury, et al., 2012d). Once permits have been obtained, traps must be appropriately labeled including the name of the responsible party conducting research, contact name and phone number, as well as the permit number (Bury, et al., 2012d). Most studies researched in this report utilized various trapping methods to sample the western pond turtle. Trapping or capturing turtles can enable the assessment of various population factors, such as demographic structure, sex ratio, and other individual parameters (Bury, et al., 2012d). Some of the different trapping methods often used in the sampling of the WPT include commercial collapsible traps (Figure 3), fyke traps (Figure 4) (or drift fence or mesh traps), and hand trapping (or muddling) (Bury, et al., 2012d). Muddling is described as wading through shallow water and simply feeling with your hands until a turtle is encountered. While muddling, your head and chest should typically remain above water and must be agencyapproved as part of a safety plan for working near water systems (Bury, et al., 2012d). Commercial traps are most often used to capture crayfish and other types of fish; however, it has been discovered that medium sized traps work well in trapping the WPT (Bury, et al., 2012d). This trap design is approximately 70 cm long containing a flat bottom which prevents the trap from rolling. Dome-shaped covers which stand 33 cm tall provides enough room for turtles to reach the air (Bury, et al., 2012d). Fyke traps, commonly referred to as drift fence or drift mesh traps, may be used with or without bait (Bury, et al., 2012d). Traps usually measure 1 12

14 m tall X 10 to 20 m long attached with floats on top to ensure turtle individuals ability to reach air. The ends of the fence or mesh, is attached to the openings of the traps where each fence ends. When turtles encounter the drift fence, they are led into the traps (Bury, et al., 2012d). In a study conducted by Bider and Hoek (1971), research teams used muddling (or hand trapping) as one of the sampling methods used to determine what sampling methods could have the most potential risk for biases in turtle sampling techniques. In that study, research teams went out into shallow water and felt through an array of aquatic vegetation to hand capture turtles for the study (Bider and Hoek, 1971). Furthermore, in a study done by Rathbun, et al., (2002), the WPT was captured by hand in shallow waters so that transponders could be placed on the shells of WPT specimens for monitoring. Other studies have relied on the use of commercial collapsible traps to sample the WPT. In a study focused on terrestrial land use of western pond turtles in a Mediterranean climate, commercial collapsible traps were used, baited with canned sardines over four successive days during the spring and fall (Rathbun, et al., 2002). Another study was found to have used predominately commercial traps, but also used homemade fyke traps as well, all baited with cans of sardines in soybean oil (Germano and Bury,2001). In that study, a total of 17 sites were sampled, each equipped with as many as eight traps and were left out for a total of one day (Germano and Bury 2001). Additionally, in a study surrounding the ecology of the WPT, Germano (2010), used both commercial traps and fyke traps as well. That study trapped western pond turtle specimens over the course of a few years using both combinations of trap designs, all baited using canned sardines (Germano, 2010). 13

15 Results Visual Encounter Surveys Visual encounter surveying is a field method most often used in the observation of the WPT (Bury, et al., 2012c). The VES survey can be extremely beneficial over expansive areas or when working with limited resources (Bury, et al., 2012c). However, there are restrictions associated with VES surveying relating to replication, and length of observation times. Data collected can prove to be inaccurate when comparing counts of occurring turtles amongst different study sites (Bury, et al., 2012c). For this reason, caution is warranted for visual observations used in concluding relative abundance (Bury, et al., 2012c). The WPT is classified as an ectotherm (relying on external energy sources to regulate body temperatures), manifesting ideal VES surveying times to be during basking periods (Bury, et al., 2012c). In most cases of aerial basking, the WPT is visible as it perches itself upon logs are rocks, however, these turtles have developed strong senses of eyesight and hearing and respond quickly in response to perceived threats (e.g., approaching surveyors) (Bury, et al., 2012c). Furthermore, many of these turtles participate in aquatic basking where they can remain covered in the water, thus staying hidden from observers leading to inaccurate counts of individuals present in a population (Bury, et al., 2012c). Trapping In many cases, trapping is regarded as the best technique for the capturing of the WPT in aquatic habitats especially in the presence of cloudy water, abundant vegetation and muddy terrains (Bury, et al., 2012d). Capture by hand, or muddling, is typically preferred in sites with 14

16 flowing water, however capturing by hand has a strong potential to bring bias into studies if there are inconsistencies between collectors and selected habitats (Bury, et al., 2012d). There are also risks associated with muddling due to reaching in underwater cervices where snapping turtles or venomous snakes may be present (Bury, et al., 2012d). Aside from the potential of being bitten by other species present within the WPT habitat, is the danger of being injured by debris and garbage hazards that may exist underwater (Bury, et al., 2012d). Furthermore, the muddling technique has shown higher amounts of juvenile turtles being captured versus adults, thus making muddling an ideal technique for assessing juvenile specimens present within populations (Bury, et al., 2012d). Commercial collapsible traps have been reported as being the top choice in trapping WPT specimens due to their efficiency, relative low cost, and portability. Being both portable and lightweight, these traps also lend themselves to being easily positioned in secluded water sources, away from predation and vandalism risks (Bury, et al., 2012d). The addition of bait (e.g.; tuna or sardine cans) to the traps may or may not be used, although there has been no significant data supporting the claim of increased capture (Bury, et al., 2012d). Fyke traps are also effective with or without the incorporation of bait. A benefit of these traps however, is that they can be assembled in two different ways: set in free standing open waters or positioned along the edge of a pond or other water system where turtles are intercepted moving across terrestrial substrates (Bury, et al., 2012d). This trap design has shown success in trapping the WPT locally in the tributaries of the Sacramento river as well as other large rivers of the eastern United states, however, these traps have not been tested extensively in western North America for reasons including: bulkiness, expense, and long set up times (Bury, et al., 2012d). 15

17 As observed in the methods section of this report, many studies have relied on the implementation of multiple sampling designs, as it is understood that utilizing a single method may greatly increase biases amongst collected samples (Bury, et al., 2012d). An example of this occurrence can be illustrated by an unusually low representation of female turtles resulting from relying solely on aquatic traps during nesting seasons (Bury, et al., 2012d). Discussion Associated with traps, are increased risks of turtle mortality and bycatch (unwanted aquatic creatures caught during commercial fishing or sampling of different species) (Bury, 2011). It has been shown that traps which allow turtles the ability to receive adequate oxygen levels and are checked regularly, have shown significant decreases in turtle mortality (Bury, 2011). If trapped turtles found within traps are unresponsive of appear dead, it is recommended that the turtle is placed into a dry bucket and placed under a shaded area. The WPT has shown a capability to recover from anoxia (lack of oxygen) and may in fact make return to its normal state (Bury, et al., 2012d). Monitoring and Conservation Many of the studies researched for this project utilized many techniques involving trapping the WPT. Many of these methods were used as part of a way of monitoring existing turtle populations. Using a method known as radiotelemetry, radio transmitters were placed on the carapace of turtles and electronically monitored as to learn more about activity patterns, microhabitat use, reproduction, and behavior (Ashton, et al., 2012). 16

18 Monitoring of the WPT can be done in a variety of ways including VES surveying and installing radio transmitters, however to significantly increase the survival of the WPT, different strategies geared at restoring and protecting habitat across its range are greatly needed (Haws, et al., 2012). Ecosystem management is driven by flexibility found in monitoring and constructed on proven knowledge of ecological mechanisms that sustain diversity and function (Bodie, 2001). Moreover, ecosystem management incorporates current habitat conditions and combines them with the processes of natural ecosystems as well as disturbance effects, and facilitate them to healthy futures (Haws, et al., 2012). Numerous conservation principles are essential to a successful ecosystem conservation based plan. As directly stated by Haws, et al., (2012), are the listed conservation principles which prove to be essential in ecosystem management. They are as follows: 1.) Species that are well distributed across their range are less prone to extinction than species that are restricted to small portions of their range. 2.) Large, intact blocks of habitat with many individuals present are more likely to persist than small fragmented blocks of habitat with few individuals. 3.) Habitat patches that are in close proximity, are preferable to more widely dispersed habitat. 4.) Habitat between protected areas that more closely resembles suitable habitat for all species is more easily and successfully traversed by dispersing individuals. 5.) Connected populations are better than disjointed ones. By initiating projects based on these principles, the WPT as well as other species within their ecosystems, should see improvements in their fitness (Haws, et al., 2012). As part of a well-integrated conservation plan, processes of preservation, restoration, and mitigation should all be incorporated as part of an adapted management approach (Haws, et al., 2012). Additionally, young WPT hatchlings require areas with shallow water and so it is essential that 17

19 recently built ponds or restored wetlands, incorporate as much natural habitat characteristics to ensure populations are maintained once introduced (Haws, et al., 2012). Conclusion The western pond turtle has seen significant declines in its population across most of its range establishing itself as a threatened species. The main causes of western pond turtle population declines can be directly attributed to anthropogenic activities which have led to habitat loss. Urbanization, agricultural land use, and changes to water systems have all effected the survival of the WPT, further exacerbating associated impacts as human populations continue to grow. While federal listing as an endangered species has not been granted, California, Oregon, and Washington have designated the WPT as either endangered or as a species of special concern. Consequently, these states have implemented many habitat conservation and restoration projects in hopes of reestablishing the WPT across its range, many with great success. This report focused its research on the examination of the species including its history, biology, habitat preferences, status, as well as current sampling techniques to better understand the methods in which to care for current populations, particularly those found at Bushy Lake in Sacramento, California. It is critical that all aspects of a species are understood before initiating any type of conservation plan, especially in regards to a species behavior and habitat preferences. This study has concluded that sampling and monitoring techniques are more efficient and successful when used in combination with each other, ensuring that populations are properly and adequately represented. 18

20 Moving forward, it is imperative that habitats are conserved, preserved, and restored for this species to increase it populations and increase its survival. The WPT is extremely resilient and possesses unique characteristics manifesting its ability for survival. It is with great hope that the information provided in this report can assist in future habitat conservation and restoration projects and grow existing WPT populations. The western pond turtle, has faced and continues to face many challenges ahead, however with the proper knowledge of biology, habitat, and history, many of those challenges can be mitigated. At Bushy Lake in Sacramento, California, restoration and preservation efforts are underway under the leadership and supervision of Dr. Michelle Stevens. Bushy Lake offers a unique opportunity for researching Western Pond Turtle populations as well as applying many of the methods and techniques examined in this report. With a small WPT population already inhabiting the restoration site, studying proper monitoring strategies and conservation efforts establishes Bushy Lake as being invaluable and offers a chance in making significant differences pertaining to the fitness of this turtle species. 19

21 Figures Figure 1: Range and distribution of the western pond turtle. This species is endemic only to the western portion of the North American Continent ( 20

22 Figure 2: Image of female western pond turtle basking. Notice coloration and distinct spotting on throat area ( Figure 3: Commercial collapsible trap attached with floatation devices to ensure turtles ability to reach the surface for air ( 21

23 Figure 4: Traditional fyke trap with drift fences on both sides of the opening to assist in guiding turtles in to the trap. Traps can be used in the water or on land. Three anchors are used to keep the trap in place ( 22

24 Literature Cited Ashton, D.T., K. Beal, S. Wray, N.E. Karraker, D.A. Reese, K.E. Schlick, F. Slavens, K. Slavens, and R. Goggans, Field Procedures in: Western Pond Turtle: Biology, Sampling Techniques, Inventory and Monitoring, Conservation, and Management, Northwest Fauna (The Society for Northwestern Vertebrate Biology), Olympia, pp Bider, J.R. and W. Hoek, An Efficient and Apparently Unbiased Sampling Technique for Population Studies of Painted Turtles, Herpetologica, 27: Bodie, J.R., Stream and Riparian Management for Freshwater Turtles, Journal of Environmental Management, 62: Burbrink, F.T., C.A. Philips, and E.J. Heske, A Riparian Zone in Southern Illinois as a Potential Dispersal Corridor for Reptiles and Amphibians, Biological Conservation, 86: Bury, B. R., 2011, Modifications of Traps to Reduce Bycatch of Freshwater Turtles, The Journal of Wildlife Management, 75: 3-5. Bury, B.R., H.H. Welsh Jr, D.J. Germano, and D.T. Ashton., 2012a. Objectives, Nomenclature and Taxonomy, Description, Status, and Needs for Sampling, in: Western Pond Turtle: Biology, Sampling Techniques, Inventory and Monitoring, Conservation, and Management, Northwest Fauna (The Society for Northwestern Vertebrate Biology), Olympia, pp Bury, B.R., D.T. Ashton, H.H. Welsh Jr., D.A. Reese, and D.J. Germano, 2012b. Synopsis of Biology in: Western Pond Turtle: Biology, Sampling Techniques, Inventory and Monitoring, Conservation, and Management, Northwest Fauna (The Society for Northwestern Vertebrate Biology), Olympia, pp Bury, B.R., D.T. Ashton, and R. Horn, 2012c. Visual Encounter Surveys in: Western Pond Turtle: Biology, Sampling Techniques, Inventory and Monitoring, Conservation, and Management, Northwest Fauna (The Society for Northwestern Vertebrate Biology), Olympia, pp Bury, B.R., D.T. Ashton, D.J. Germano, N.E. Karraker, D.A. Reese, and K.E. Schlick, 2012d. Sampling of Turtles: Trapping and Snorkeling in: Western Pond Turtle: Biology, Sampling Techniques, Inventory and Monitoring, Conservation, and Management, Northwest Fauna (The Society for Northwestern Vertebrate Biology), Olympia, pp

25 Bushell, J., and Geist, N., 2012 Conservation and Research for the Western Pond Turtle, (Clemmys marmorata), in Northern California, Animal Keepers Forum, vol. 39, p Ernst, C.H., J.E. Levich, and R.W. Barbour, Turtles of The United States and Canada. Smithsonian Institute Press, Washington D.C. Germano, D.J and Bury, R.B., 2001, Western Pond Turtles (Clemmys marmorata) in the Central Valley of California: Status and Population Structure, Transactions of the Western Section of The Wildlife Society, 37: Germano, D.J., 2010, Ecology of Western Pond Turtles (Actinemys marmorata) at Sewage-Treatment Facilities in the San Joaquin Valley, California, The Southwestern Naturalist, 55: Germano, D.J., and Rathbun, G.B., 2008, Growth, Population Structure, and Reproduction of Western Pond Turtles (Actinemys marmorata) on the Central Coast of California, Chelonian Conservation and Biology, 7: Giese, C.L.A., N.D. Greenwald, and T. Curry, Petition to List 53 Amphibians and Reptiles in the United States as Threatened or Endangered Species Under the Endangered Species Act. Haws, C., R. Horn, K. Beal, L. Todd, S. Wray, S. Wessel-Kelly, and B.R. Bruce, Conservation and Restoration Strategies in: : Western Pond Turtle: Biology, Sampling Techniques, Inventory and Monitoring, Conservation, and Management, Northwest Fauna (The Society for Northwestern Vertebrate Biology), Olympia, pp Jennings, M.R., and Hayes, M.P., 1994, Amphibian and Reptile Species of Special Concern in California, (Report No. 8023), California Department of Fish and Game, Rancho Cordova, CA, Inland Fisheries Division. Rathbun, G.B., N.J. Scott Jr, and T.G. Murphey, Terrestrial Habitat Use by Pacific Pond Turtles in a Mediterranean Climate, The Southwestern Naturalist, 47: Reese, D.A., Comparative demography and habitat use of western pond turtles in Northern California; the effects of damming and related alterations. Unpubl. Ph. D. Diss. University California, Berkeley. Reese, D.A., and Welsh, H.H., 1997, Use of Terrestrial Habitat by Western Pond Turtles, Clemmys marmorata, Implications for Management, New York Turtle and Tortoise Society, pp

26 Soule, M.E., Biodiversity indicators in California: taking nature s temperature. California Agriculture, 49: Thomson, R.C., et al., 2010, Distribution and Abundance of Invasive Red-Eared Sliders (Trachemys scripta elegans) in California s Sacramento River Basin and Possible Impacts on Native Western Pond Turtles (Emys marmorata), Chelonian Conservation and Biology, 9: