Small Turtles Research Articles

Overwintering site fidelity and communal hibernation predispose Northern Map Turtles to mass mortality events

Mass mortality events appear to be increasing in intensity and frequency, so understanding their causes and consequences is imperative for wildlife conservation. We report on a mass mortality event in a population of Northern Map Turtles ( Graptemys geographica (LeSueur, 1817)). At a communal overwintering site, 142 carcasses (ca. 10% of population) were recovered, seemingly depredated by river otters ( Lontra canadensis (Schreber, 1777)). We compared the size and sex of the carcasses to those of turtles that survived. Smaller turtles and males were more likely to be depredated than larger turtles and females. Using captures made at the same overwintering site between 2003 and 2022, we assessed the vulnerability of this population to mass mortality events during winter. Nearly 60% of the 1875 turtles marked between 2003 and 2022 used the overwintering site where the mass mortality event occurred at least once. On average, turtles overwintered at the site at least 38% of the winters between their first and last capture. Our study shows how behaviour and physiology interact to predispose a species to mass mortality events and ecological traps. Protecting overwintering sites and minimizing human pressures affecting winter depredation may be essential for the preservation of certain turtle populations.

Multistate outbreak of turtle-associated salmonellosis highlights ongoing challenges with the illegal sale and distribution of small turtles.

The sale and distribution of small turtles (shell length <4 inches) as pets has been banned in the United States since 1975 because of the risk of Salmonella transmission, especially to children. Despite this 48-year-old ban, salmonellosis outbreaks continue to be linked to contact with small turtles. During investigations of turtle-associated outbreaks, information regarding the turtle farm of origin is difficult to obtain because turtles are commonly sold by transient vendors. During 2020-2021, public health officials investigated a multistate illness outbreak caused by Salmonella enterica serotype Typhimurium linked to pet small turtles. Cases were defined as a laboratory-confirmed Salmonella Typhimurium infection highly related (within 0-6 allele differences) to the outbreak strain based on whole-genome sequencing analysis by core-genome multilocus sequence typing with illness onset occurring during 27 August 2020-14 May 2021. Forty-three patients were identified from 12 states; of these, 35% (15/43) were children <5 years old. Among patients with available information, 37% (14/38) were hospitalized, and one death was reported. Seventy-four percent (25/34) of patients reported turtle exposure in the week before illness onset, and 84% (16/19) specified exposure to small turtles. The outbreak strain was isolated from samples collected from a Pennsylvania patient's small turtle tank. Two patients reported purchasing their small turtles from pet stores. Salmonella Braenderup was isolated from samples collected from small turtles and their habitat at one of these stores; however, at that time, this strain was not associated with any human illnesses. This investigation was notable because of the documented sale of small turtles from several pet stores combined with the identification of a single small turtle supplier to these pet stores. The high proportion of children involved in this outbreak highlights the continued need to educate the pet industry as well as parents and caregivers about the risk of turtle-associated salmonellosis especially in children. Understanding and addressing the persisting challenges related to the illegal sale and distribution of small turtles could reduce the burden of turtle-associated salmonellosis.

Using baited remote underwater videos to survey freshwater turtles

AbstractNew and innovative techniques utilizing underwater cameras have the potential to track changes in turtle populations whilst being less invasive and time intensive than traditional trapping surveys. In this study, we trialled the use of Baited Remote Underwater Videos (BRUVs) in five upland streams to test if BRUVs could be used for abundance, size and sex estimates of freshwater turtles. We also compared BRUVs to cathedral traps and identified key considerations for future use of this method, such as whether the time of day influenced results. Our study successfully detected 83 turtles from 52 h of footage and identified all species known to occur in the study area. The deployment time did not significantly influence relative abundance. BRUVs also produced statistically similar catch per unit effort estimates to cathedral trapping techniques. No small turtles (i.e. juveniles) were detected, and difficulties with visibility, sex accuracy and carapace measurements are discussed for future BRUV use. Our study shows that BRUVs are a useful, time effective, non‐invasive technique to collect relative abundance and species richness estimates for freshwater turtles.

Movement ecology of adult and juvenile spotted turtles (Clemmys guttata) in a seasonally dynamic environment

Context Understanding the temporal and spatial scales at which wildlife move is vital for conservation and management. This is especially important for semi-aquatic species that make frequent inter-wetland movements to fulfil life-history requirements. Aims We aimed to investigate the drivers of movement and space-use of the imperilled spotted turtle (Clemmys guttata), a seasonal wetland specialist, in three large, isolated wetland complexes in Virginia, USA. Methods We used VHF radio-transmitters to radio-locate adult and juvenile turtles, and estimated movement and space-use during their active and aestivation seasons (March–August). We then used generalised linear mixed models to examine how movement and space-use varied, based on intrinsic turtle characteristics and extrinsic wetland and climatic factors. Key results We show that, on average, individual spotted turtles used five wetlands per year (range 3–13), and that their inter-wetland movement and movement distance varied seasonally in accordance with wetland availability and breeding phenology. Spotted turtle movement and space-use was influenced by the arrangement and size of the wetland complexes, with turtles moving further and occupying larger home-ranges as size and distance between wetlands increased. Inter-wetland movement was not influenced by intrinsic turtle effects but larger adult turtles moved further, used more wetlands, and had larger home-ranges than smaller turtles. Conclusions Turtle responses to variation in season and wetland configuration highlight the need for complex and dynamic landscapes required to sustain this species. Implications This study has important conservation implications showing that spotted turtles rely on a large number of diverse wetlands, as well as upland habitat, to fulfil their resource needs – and that these habitat associations vary seasonally. Results from our study can aid the understanding of spatial and temporal variation in patch characteristics (e.g. quality and extent) and inter-patch movement by organisms, which is critical for the conservation and management of semi-aquatic species and other organisms that occupy patchy habitat complexes.

Online sale of small turtles circumvents public health regulations in the United States.

In the United States (U.S.), pet turtles have been associated with outbreaks of salmonellosis, a serious and sometimes-fatal intestinal illness caused by Salmonella bacteria, with nearly 300,000 people being infected in some years. Children are particularly susceptible because of their propensity to put items, including small turtles, in their mouths. In 1975, a U.S. federal regulation prohibited the sale of turtles <4 inches (101.6 mm) in size, except for the purposes of export, scientific, or educational purposes. This regulation was established to reduce the incidence of salmonellosis, particularly in small children. Previous research has not evaluated the availability of turtles <4 inches in size on websites selling wildlife. We monitored 16 websites in 2021 and quantified listings of small turtles. We determined whether information on Salmonella, the 1975 federal regulation, or related state regulations were provided on the websites and determined legality of sales of small turtles by state regulations. We found that all 16 websites openly advertised and sold turtles <4 inches in size, but only half of these websites provided information about Salmonella and/or the federal regulation. These websites required buyers to confirm that they were not purchasing a turtle as a pet, thereby putting the onus on the consumer to adhere to the regulation. We documented 515 listings of turtles <4 inches in size, including 47 species and one hybrid. Our study has demonstrated that internet sales of small turtles currently represent part of the thriving online pet trade in the U.S. Enforcement of the federal regulation faces jurisdictional challenges in most states. Therefore, we recommend continued public education campaigns by public health agencies in the U.S. to help reduce the risk that pet turtle ownership presents.

An alternative interpretation of small-bodied turtles from the “Middle Purbeck” of England as a new species of compsemydid turtle

A series of small-sized fossil turtles were collected from Beckles’ Pit, Durlston Bay, Dorset, United Kingdom in 1856 from a sediment package referable to the Early Cretaceous (Berriasian) Purbeck Group. The two primary accounts that previously documented these turtles concluded that they represent the juveniles of the coeval early pleurosternid Pleurosternon bullockii. A brief, third account, however, suggested that these may represent a new species of compsemydid turtle. We here highlight a series of discrete morphological characters that consistently distinguish the small-bodied turtles from Beckles’ Pit from large-bodied Pleurosternon bullockii, in particular the arrangement of the bones and scutes along the anterior margin of the shell. As these characters are otherwise used to diagnose new species of turtles, in particular compsemydids, and to establish the phylogeny of fossil turtles, we side with the latter interpretation and name a new taxon of early compsemydid, Tongemys enigmaticagen. et sp. nov. The early record of compsemydid is restricted to the Early Cretaceous of Europe, but is extremely fragmentary. We suggest that this may be a bias towards the collection and identification of small turtle remains, but also that a re-study of Early Cretaceous continental turtle faunas is likely to yield further material.

Multistate reptile- and amphibian-associated salmonellosis outbreaks in humans, United States, 2009-2018.

Non-typhoidal Salmonella cause an estimated 1.4 million human illnesses, 26,000 hospitalizations and 400 deaths annually in the United States. Approximately 11% of these infections are attributed to animal contact. Reptiles and amphibians are known sources of salmonellosis; young children (aged <5 years) are disproportionately affected by reptile- and amphibian-associated salmonellosis (RAAS) outbreaks. We describe multistate RAAS outbreaks to characterize illnesses and inform prevention efforts. RAAS outbreaks were defined as ≥2 culture-confirmed human Salmonella infections with similar pulsed-field gel electrophoresis patterns and epidemiologic, laboratory or traceback evidence linking them to a common reptile/amphibian exposure. Data sources included the Animal Contact Outbreak Surveillance System; CDC Outbreak Response and Prevention Branch's outbreak management database; PulseNet, the national molecular subtyping network for foodborne disease surveillance in the United States; and the National Antimicrobial Resistance Monitoring System. Twenty-six RAAS outbreaks were reported during 2009-2018, resulting in 1465 illnesses and 306 hospitalizations. The outbreaks were associated with turtles (19), lizards (5), snakes (1) and frogs (1). Sixteen (61.5%) outbreaks were linked to small turtles (<4 inches), resulting in 914 illnesses. Forty-nine percent of outbreak-associated patients were aged <5 years. Of 362 patients/caregivers interviewed, 111 (30.7%) were aware that reptiles/amphibians can carry Salmonella. Among 267 patient isolates with antimicrobial susceptibility information, 20 (7.5%) were non-susceptible to ≥1 antibiotic used to treat human salmonellosis. RAAS outbreaks result in considerable morbidity, particularly among young children. Illnesses linked to small turtles are preventable through education, targeted outreach to caregivers and paediatricians, and when appropriate, enforcement. Historically, individual states and jurisdictions have enforced existing or promulgated new authorities to address outbreaks. Preventing future RAAS outbreaks requires addressing challenges related to the illegal sale/distribution of small turtles; and for legal reptile sales, providing information on RAAS risk to consumers at point of sale to support informed pet ownership decisions.

A half-century of demographic changes in a green turtle (Chelonia mydas) foraging aggregation during an era of seagrass decline

To understand the demographic responses of green turtles to seagrass decline, we examined a data set from study of a mixed-stock foraging aggregation of immature green turtles, Chelonia mydas, collected in Bermuda (32o18’N, − 64o46’W) over five decades. Average turtle size (SCLmin) and mass declined by 22.3% and 58.2%, respectively. Aggregation size structure shifted to smaller sizes and now consists of more small turtles and fewer large turtles. Density (turtles ha−1) increased significantly but biomass (kg ha−1) remained unchanged and low compared to C. mydas biomass observed elsewhere. Green turtles exhibited reduced site fidelity during two portions of the study period, suggesting increased foraging effort. Reduction in turtle body condition index and seagrass coverage occurred from offshore to inshore. Changes in aggregation composition and behavior were consistent with expectations given a documented decline in seagrass availability, combined with increased output from source rookeries. Apparent response to resource decline is traced back to 1976, well before seagrass loss was first documented. Green turtles and their primary food source (Thalassia testudinum) are at the northern limit of their range in Bermuda, where seagrasses would be expected to have a reduced tolerance for natural grazing pressure and increased susceptibility to synergistic stressors, especially temperature, bioturbation and phosphorus limitation. Our results suggest that synergistic stressors, and not green turtles alone, have produced the observed reduction in seagrasses on the Bermuda Platform. Given that seagrass declines have been reported worldwide, our findings may suggest how green turtles will respond elsewhere.

Plastic ingestion by green turtles (Chelonia mydas) over 33 years along the coast of Texas, USA

Despite exponential growth of anthropogenic marine debris in recent decades, plastic ingestion by marine turtles in the Gulf of Mexico is not well understood. Gastrointestinal tracts were examined from 464 green turtles that stranded in Texas between 1987 and 2019, and 226 turtles ingested plastic (48.7%). This number doubled from 32.5% in 1987–1999 to 65.5% in 2019, but mass of ingested items was lowest in 2019. No turtles showed evidence of death directly related to plastic ingestion. Compared to other regions, plastic ingestion was low. Small turtles (<25 cm straight carapace length) ingested plastic more frequently and in greater amounts than larger turtles. Small turtles also ingested more hard plastic while larger turtles ingested more sheet-like and thread-like plastics, which may correspond to size-based habitat shifts. This is among the largest marine turtle ingestion studies to date and demonstrates an increasing prevalence of plastic ingestion.

Characterization of Salmonella spp. isolated from small turtles and human in Republic of Korea

In 2013, the World Health Organization (WHO) reported that small, pet turtles had caused multistate Salmonella outbreaks in the United States, from where small turtles were subsequently exported into the Republic of Korea. We investigated cases of salmonellosis in South Korea associated with domestic small turtles and analysed genetic characteristics of Salmonella isolates in commercially-available small turtles. We traced six Salmonella serovars, known to have caused human infection in the United States (S. Sandiego, S. Pomona, S. Poona, S. Newport, I 4,(5),12:i:-, and S. Typhimurium), in isolates from suspected Salmonella infection cases in Korea from 2006 to 2015. Additionally, we conducted a pilot study of isolates from small turtles being sold in Korean markets, and performed molecular genetic analysis on the identified strains. S. Pomona was identified in one Salmonella infection case, while all strains isolated from small turtles belonged to either subspecies I (enterica, n = 10, 71.4%) or subspecies IIIb (diarizonae, n = 4, 28.6%). Two serovars (S. Pomona and S. Sandiego) that were highly associated with turtle-to-human transmission were identified with 100% homology to human isolates. Previous to this study, turtle-associated human S. Pomona infections were not well reported in Korea. We report Salmonella infection in small turtles in Korea, and confirm that small turtles should be considered the first infectious agent in S. Pomona infection. We therefore suggest quarantine measures for importing small turtles be enhanced in Korea.

Investigations of Possible Multistate Outbreaks of Salmonella, Shiga Toxin-Producing Escherichia coli, and Listeria monocytogenes Infections - United States, 2016.

Investigations of Possible Multistate Outbreaks of Salmonella, Shiga Toxin-Producing Escherichia coli, and Listeria monocytogenes Infections - United States, 2016.

Historical museum collections and contemporary population studies implicate roads and introduced predatory bullfrogs in the decline of western pond turtles.

The western pond turtle (WPT), recently separated into two paripatrically distributed species (Emys pallida and Emys marmorata), is experiencing significant reductions in its range and population size. In addition to habitat loss, two potential causes of decline are female-biased road mortality and high juvenile mortality from non-native predatory bullfrogs (Rana catesbeiana). However, quantitative analyses of these threats have never been conducted for either species of WPT. We used a combination of historical museum samples and published and unpublished field studies shared with us through personal communications with WPT field researchers (B. Shaffer, P. Scott, R. Fisher, C. Brown, R. Dagit, L. Patterson, T. Engstrom, 2019, personal communications) to quantify the effect of roads and bullfrogs on WPT populations along the west coast of the United States. Both species of WPT shift toward increasingly male biased museum collections over the last century, a trend consistent with increasing, female-biased road mortality. Recent WPT population studies revealed that road density and proximity were significantly associated with increasingly male-biased sex ratios, further suggesting female-biased road mortality. The mean body size of museum collections of E. marmorata, but not E. pallida, has increased over the last 100 years, consistent with reduced recruitment and aging populations that could be driven by invasive predators. Contemporary WPT population sites that co-occur with bullfrogs had significantly greater average body sizes than population sites without bullfrogs, suggesting strong bullfrog predation on small WPT hatchlings and juveniles. Overall, our findings indicate that both species of WPT face demographic challenges which would have been difficult to document without the use of both historical data from natural history collections and contemporary demographic field data. Although correlational, our analyses suggest that female-biased road mortality and predation on small turtles by non-native bullfrogs are occurring, and that conservation strategies reducing both may be important for WPT recovery.

Behavioural and physiological responses to simulated predator-induced stress in the eastern box turtle, Terrapene carolina carolina

Abstract In spite of the fully-hinged shell being the defining characteristic of box turtles, few studies have quantified the behavioural use of the shell in response to predator encounters. While it is often assumed that box turtles simply withdraw into their shell in response to threats, we expected variability among individuals in shell usage and in the degree of head and limb retraction because withdrawal is likely to be costly. We tested the behavioural and physiological responses of free-ranging eastern box turtles to stimuli of varying intensity: observation only, a visual stimulus, a poke on the leg, or a pinch on the leg before being flipped. The more intense the simulated predatory stimulus, the more likely turtles were to fully close their shell. However, stimulus intensity did not affect plasma corticosterone or lactate levels. This may be due to too brief or weak of a stimulus, increased parasympathetic activity, or seasonal effects. Upon capture and during handling, almost all turtles withdrew into their shells and closed their anterior plastron, although fewer closed their posterior plastron, and a few engaged in other behaviours such as biting and urinating. Older, larger turtles were able to close their shells with greater strength than younger and smaller turtles. Our results indicate that in spite of their fully closable shell, box turtles exhibit a graded response to perceived threats. This suggests that full closure of the shell is likely to be costly and occurs only in response to the most intense stimuli.

Lower Eocene Footprints from Northwest Washington, USA. Part 1: Reptile Tracks

Lower Eocene fluvial strata in the Chuckanut Formation preserve abundant bird and mammal tracks. Reptile trace fossils include footprints from a small turtle (ichnogenus Chelonipus), and several Crocodylian trackways that consist of irregularly spaced footprints associated with linear tail drag marks. The latter trackways represent “punting” locomotion, where a submerged Crocodylian used intermittent substrate contacts to provide forward motion of their neutrally buoyant bodies. Two adjacent sandstone blocks preserve Crocodylian trace fossils that are named herein as a new ichnogenus and ichnospecies Anticusuchipes amnis. Two other Crocodylian trackways lack sufficient detail for ichnotaxonomic assignment.

Diverse foraging habits of juvenile green turtles (Chelonia mydas) in a summer-restricted foraging habitat in the northwest Pacific Ocean

Green turtles in year-round neritic foraging habitats are widely considered to have small home ranges and to mainly feed on plant-based diets. In contrast, few studies have examined the summer-restricted habitats to which these turtles seasonally migrate. In this study, we investigated the foraging habits of green turtles migrating to the Sanriku Coast, a summer-restricted foraging habitat in a temperate area (38–39°N) of the northwest Pacific Ocean, using stable isotope analysis and biologging experiments from 2007 to 2015. Stable isotope analysis (n = 40, straight carapace length (SCL): 36.8–90.9 cm) indicated that most of the turtles, especially all smaller turtles (n = 35, SCL < 58 cm), relied on gelatinous prey before arriving at the Sanriku Coast. According to the biologging experiments (451.2 h of behavioral data and 43.2 h of video data, n = 6, SCL: 44.5–81.0 cm), the turtles shifted their main food to macro-algae (135 out of 148 feeding events) and consumed it at the sea bottom during their stay in the specific localized area of the Sanriku Coast. However, the turtles still consumed gelatinous prey in midwater during their movement to other locations along the Sanriku Coast and/or during their migration to southern overwintering habitats (13 events). These results indicated that green turtles migrating to the Sanriku Coast exhibit dietary diversity relative to year-round habitats, and the turtles in this area seem to consume gelatinous prey during the transit period in addition to feeding on macro-algae during the resident period.

Morphometric Models of Growth in Ornate Box Turtles (Terrapene ornata ornata) as Related to Growth Rings

Few studies document early growth of hatchling turtles. We fit growth models to 606 carapace length (CL) measurements of ornate box turtles (Terrapene ornata ornata) for 231 males, 226 females, and 53 individuals of undetermined sex. We used the Richards model to fit 95% confidence bands and 95% prediction bands on the best-fit curves for males and females. We also computed Spearman's rho correlation relating growth ring counts to CL and plotted change in CL for 131 recaptured individuals (45 males, 57 females, and 29 individuals of undetermined sex) for which we had two or more measurements from different years. There was a strong correlation between CL and number of growth rings. Using the properties of the derivative of Richards growth model, juvenile 1, juvenile 2, subadult, and adult stages were defined for male and female growth. Our overall growth models were similar to those for studies of ornate box turtles in Kansas and South Dakota and the desert box turtle (T. o. luteola) in New Mexico; however, our growth stages were defined by smaller turtles. Unlike a previous study in South Dakota, our adult males were larger than adult females. Prior to a CL of approximately 86 mm and 8 growth rings, the carapace grew faster than the plastron, after which the plastron grew faster than the carapace. Five hatchlings' plastra grew an average of 26% (SD = 14%) the first year and the carapace grew an average of 15% (SD = 7%). During the first 3 yrs, most individuals developed only one growth ring per year. If major growth rings approximate age, size can be used to estimate age in ornate box turtles up to 60–90 mm (about 8 growth rings). Between 8 and 12 growth rings, size and age are also correlated, but accuracy of age estimates decreases. Life-history traits such as age at reproductive maturation and size at which individuals are vulnerable to predation are important to assess long-term viability of a population; therefore, understanding environmental impacts on individual growth is important for conservation planning and management of this threatened species in Iowa.

Using mixed stock analysis to assess source populations for at‐sea bycaught juvenile and adult loggerhead turtles (Caretta caretta) in the north‐west Atlantic

AbstractAssessments of fisheries by‐catch on marine megafauna are important for developing effective management strategies. For sea turtles, impacts may be evident in nesting population trends, but generally only after a lag, as turtles are slow to mature. We examined 850 loggerhead turtle (Caretta caretta) by‐catch samples collected over 14 years throughout the western North Atlantic to identify source nesting populations. We identified proportions of turtles from 19 distinct management units (MUs), using mitochondrial DNA and mixed stock analysis, considering population size. We found a significant split in the distribution of small versus large loggerheads to the north and south of Cape Hatteras, North Carolina (latitude 35°N). North of Cape Hatteras, large turtles came from south‐east Florida (SEFL; 44% ± 15%) and the northern United States (33% ± 16%) MUs, while south of Cape Hatteras, the major contributors were Central East Florida (52% ± 20%) and south‐east Florida (SEFL; 41% ± 20%). Small turtles in the north came from Central East Florida (64% ± 14%), and in the south, south‐east Florida had the highest representation (56% ± 25%). There was little contribution from Mediterranean and Cape Verde populations, indicating low risk from western North Atlantic by‐catch to MUs in the Mediterranean. Understanding where threats may impact source populations is important, particularly for larger size turtles, as these individuals have the highest reproductive value. These findings allow more informed threat assessments to be conducted for loggerhead turtles considering spatial and demographic structure.

Flea market finds and global exports: Four multistate outbreaks of human Salmonella infections linked to small turtles, United States-2015.

Zoonotic transmission of Salmonella infections causes an estimated 11% of salmonellosis annually in the United States. This report describes the epidemiologic, traceback and laboratory investigations conducted in the United States as part of four multistate outbreaks of Salmonella infections linked to small turtles. Salmonella isolates indistinguishable from the outbreak strains were isolated from a total of 143 ill people in the United States, pet turtles, and pond water samples collected from turtle farm A, as well as ill people from Chile and Luxembourg. Almost half (45%) of infections occurred in children aged <5years, underscoring the importance of the Centers for Disease Control and Prevention recommendation to keep pet turtles and other reptiles out of homes and childcare settings with young children. Although only 43% of the ill people who reported turtle exposure provided purchase information, most small turtles were purchased from flea markets or street vendors, which made it difficult to locate the vendor, trace the turtles to a farm of origin, provide education and enforce the United States federal ban on the sale and distribution of small turtles. These outbreaks highlight the importance of improving public awareness and education about the risk of Salmonella from small turtles not only in the United States but also worldwide.

The effects of climate on annual variation in reproductive output in Snapping Turtles (Chelydra serpentina)

Reptiles are highly dependent on climatic patterns to regulate their behavior and physiology, and studies of the effects of climate on the biology of organisms are increasingly important given expected climate change. Our study examined the effects of climate variation over 15 of the 26 years between 1990 and 2015 on the reproductive output of the Snapping Turtle (Chelydra serpentina (Linnaeus, 1758)). Egg mass, clutch size, and clutch mass (relative to body size) were significantly higher in years following warmer temperatures in September and October of the year before reproduction, but not related to temperatures in April and May just before reproduction. Of the above life-history traits, egg mass varied the least across years, and after warm autumns small turtles (225–285 mm carapace length) increased clutch mass by increasing clutch size but not egg mass. In contrast, under the same conditions, large turtles increased clutch mass by increasing egg mass but not clutch size. Our data suggest optimal egg mass may vary with female size. Climate change may already have impacted reproductive output in Snapping Turtles at the site because temperatures during September and October have increased about 0.5 °C each decade for the last 45 years.

Assessment of Road Mortality in the Spotted Turtle (Clemmys guttata)

The Spotted Turtle (Clemmy guttata), a small freshwater turtle species, prefer shallow wetland habitats, and are restricted to eastern North America, predominantly in southern Ontario along the southern shores of the Great Lakes. However, the Spotted Turtle has been classified as ‘vulnerable’ (a species of special concern) by COSEWIC since 1991, owing to the 35% decline of the population throughout the past century. This is primarily of concern regarding reductions of ecosystem biodiversity, and further anthropogenic pressures will drive the species towards further endangerment. High rates of road mortality are considered a key actor in facilitating a decline in the Spotted Turtle population. A study by Ashley and Robinson (1996) found that approximately 25% of annual Spotted Turtle deaths are a direct result of roadway incidents, around the Long Point Causeway, bordering Lake Erie. By utilizing data from Long Point, the extent of road mortality of the Spotted Turtle will be characterized by analyzing the proportions of deaths in high-density versus low-density roadways. There is varied response to the effectiveness of various solutions to minimize road mortality, including a vegetation management approach boarding roadways, subterranean passages, barriers along roadsides, and influencing and informing in decision-making processes. With the Sandy Pines Wildlife Center, Napanee, reductions in roadway mortality rates will decline along the 401 by increasing both public and private sector awareness regarding the issue of Spotted Turtle road mortality. Recommendations to communities and government entities will be made to facilitate the improvement of the status of Spotted Turtle.