Search

Urbanization is a significant driver of the global biodiversity crisis. Turtles are particularly impacted by urbanization because of the vulnerability of riparian habitats to habitat loss and road mortality. Behaviour plays a crucial role in determining the success of urban animals. Behavioural responses to urbanization, however, are rarely studied in turtles even though many turtles are at‐risk and sometimes live in urban areas. Therefore, we evaluated behavioural changes in painted turtles (Chrysemys picta) living in wetlands surrounded by a gradient of urbanization. We tested the consistency of painted turtle behaviour in the laboratory and examined the behaviour of painted turtles from 24 wetland sites across an urbanization gradient in Ottawa, Ontario, Canada. We assessed: (i) aggression by measuring the number of active defensive behaviours the turtles performed in response to handling, (ii) boldness by measuring the amount of time the turtles took to emerge from their shells and move from their initial locations in a circular arena and (iii) activity by measuring the amount of time the turtles spent moving in the same circular arena. We found that all behaviours were consistent in the laboratory. We also found that as the level of urbanization increased, turtles were more aggressive and bolder. Urbanization affects painted turtle behaviour, but further research is required to understand the mechanisms responsible and the conservation implications. [ABSTRACT FROM AUTHOR]

Balancing urban development with environmental sustainability is a major challenge that is increasingly recognized in planning decisions. Urban development proposals are often approved with the expectation that deleterious impacts on native species will be constrained, but this assumption is rarely tested over sufficient timelines to confirm its validity for long‐lived, at‐risk species. We tracked changes in Blanding's turtle (Emydoidea blandingii) habitat availability and demography over 10 years near Ottawa, ON, Canada, to determine whether urban development and associated mitigation measures were sufficient to ensure long‐term population persistence. Suitable turtle habitat declined by 10% during the study, and wetland corridors were essentially lost. Habitat loss coincided with a marked reduction in adult turtle apparent survival, resulting in a 70% decline in population size. Adult females experienced the greatest decline, and despite wildlife fencing and culvert placement as conditions of project approval, turtle road mortality likely was the primary cause of the decline. Deterministic population viability analysis revealed that ~4 adult female road mortalities (of an initial 56 females) per year produced a comparable decline to that observed in our population estimates; at this rate, the population will likely breach its quasi‐extinction threshold (4 females) in under a decade. Accordingly, we infer that in our study area, approved urban development was not compatible with at‐risk turtle population viability. Our findings imply that urban development approval conditions, even when conducted in the context of seemingly robust species‐at‐risk protection, can be inadequate to ensure sustainability. We contend that if environmental sustainability is to be prioritized, urban development projects in areas occupied by at‐risk species must be subject to more stringent oversight during the planning, approval and implementation phases. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Field-Naturalist is the property of Ottawa Field Naturalists' Club and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Freshwater turtles face many threats but roadkill is one of the most serious for many species. Roadkill of turtles is not uniformly distributed across roads but aggregated in certain areas, termed hotspots. A key question in identifying hotspots is whether they are fixed locations or if they shift from year to year because of changes in movement patterns. We compared how one, two, and three years of road survey data compared with the pooled data from four years of surveys. We found 254 turtles during 73 surveys during four years along a 15.5 km road section in Ottawa, Ontario, Canada. The four years of pooled data produced four hotspots ("pooled hotspots") while each year or combination of years produced from three to five hotspots, four of which approximately corresponded to the pooled hotspots. The average percentage overlap of hotspots between one, two, or three years of survey data and the pooled hotspots ranged from 58.7% to 88.9%. Just one year of surveys sometimes missed one of the pooled hotspots, underestimated the spatial extent of the pooled hotspots, and also sometimes produced an additional "temporary" hotspot. Two years of surveys generally produced better approximations of the pooled hotspots and better identified the spatial extent of those hotspots. [ABSTRACT FROM AUTHOR]

Habitat loss and degradation have led to the extinction of many species worldwide. The endangered Blanding's Turtle (Emydoidea blandingii (Holbrook, 1838)), a semi-aquatic freshwater turtle, occupies a wide range of wetlands and landscapes primarily in southeastern Canada and the Great Lakes region of the United States. We explored whether the probability of wetland occupancy by Blanding's Turtles is affected by the surrounding landscape. We used visual surveys, environmental DNA, and Atlas data to document the presence of Blanding's Turtles in wetlands in Ottawa, Ontario, Canada. We tabulated landscape composition at multiple scales surrounding the wetlands to determine whether landscape composition can predict wetland occupancy. Generally, wetlands surrounded by forest and other undisturbed lands were most likely to harbour Blanding's Turtles, whereas those surrounded by more human-disturbed lands were least likely to harbour Blanding's Turtles. Larger wetlands and a high proportion of wetlands in the surrounding landscape also increased the probability of occupancy by Blanding's Turtles. Finally, older wetlands were more likely to be occupied by Blanding's Turtles. The ability to estimate a species' probability of occupancy can aid in conservation efforts, such as critical habitat delineation. [ABSTRACT FROM AUTHOR]

While Bitran and Tan (2013. Diaspora Nation: An Inquiry into the Economic Potential of Diaspora Networks in Canada. Toronto: Mowat Centre, University of Toronto, 8) believe that Canada (Turtle Island) is a 'diaspora nation', it is also evident that Canada as a settler colonial state has deeply rooted systemic and blatant forms of racism that have historically victimized and otherized diasporic communities of colour for the purpose of maintaining and perpetuating White hegemony. Even though cultural diversity and diasporic identities are often hailed to have underpinned Canadian 'multiculturalism', the aforementioned contradiction unravels the discourse or intent of multiculturalism in Canada – a country not fostering inclusivity, equality and justice for all the marginalized populations – but quite strikingly the opposite – the politics of Whiteness undergirded by the legacy of settler colonialism, historically. The identity of Canada as a country embracing 'multiculturalism' has a deeply rooted history of settler colonialism and its devastating consequences on Indigenous peoples living in this land for thousands of years before the arrival of White European settlers. And, of course, a plethora of studies have been done concerning those issues of racism, multiculturalism, settle colonialism and so forth in Canada. Similarly, a number of studies do exist that explore numerous diasporic identities based on their countries of origin. However, in this essay, I explore intersectional nature of three broad diasporic identities – Indigenous, Black and immigrant peoples of colour in Canada – who have common and intersecting experiences of forced/voluntary dispersal, homelessness, cultural alienation, marginalization, and so forth. Based on the intersecting experiences, the diasporas in Canada can ramp up an effective alliance to fight the injustices caused by White people through various institutions and state apparatuses. In order to critically examine the intersectionality of the three overarching diasporas and their issues, the essay uses Critical Race Theoretical (CRT) approach of intersectionality, postcolonial as well as Indigenous perspective to better understand how the diasporas are nuanced and interrelated despite their unique issues and existential characteristics. Similarly, viewing the diasporic intersection in Canada from critical race theoretical notion of intersectionality together with Indigenous perspective offers an understanding on how different diasporas in Canada and elsewhere share similar historical experiences and, at the same time, forge solidarity for their common good. On the one hand, the diasporic convergence with Indigenous peoples in it (re)fashions the Native space as an equitable space grounded on traditional Indigenous metaphor of common pot – inclusivity, renewal, mutual respect and responsibility, and on the other, it also highlights the necessity of critically (re)examining diasporas in Turtle Island by considering Indigeneity as an integral part of the discourse – study of diasporas not in isolation with Indigenous peoples, but as intersectional identities, so to speak. [ABSTRACT FROM AUTHOR]

Substituted phenylamine antioxidants (SPAs) are used in Canadian industrial processes. SPAs, specifically N-phenyl-1-naphthylamine (PNA), have received very little attention despite their current use in Canada and their expected aquatic and environmental releases. There is a research gap regarding the effects of PNA in wildlife; therefore, Chelydra serpentina (common snapping turtle) was studied due to its importance as an environmental indicator species. A chronic experiment was performed using PNA spiked food (0 to 3446 ng/g) to determine its toxicity to juvenile C. serpentina. A significant increase in cyp1a mRNA level was observed in the liver of turtles exposed to 3446 ng/g PNA, suggesting that phase I detoxification is activated in the exposed animals. Additionally, a significant decrease in cyp2b transcript level was observed at the two lowest PNA doses, likely indicating another metabolic alteration for PNA. This study helped determine the molecular effects associated with a PNA exposure in reptiles. [ABSTRACT FROM AUTHOR]

Males and females have divergent reproductive interests arising from their unequal investments in offspring. This sexual conflict drives an antagonistic arms race that influences sex-specific reproductive success. Alternative reproductive tactics are expected in long-lived species for which the reproductive strategy that maximizes mating success could differ across body sizes. The mating strategy of the painted turtle (Chrysemys picta) has been characterized as an elaborate and amiable male courtship display during which males use their elongate foreclaws to stroke females, coupled with female mate choice. Contrary to this long-held understanding, in situ field observations and experimental trials from our long-term study in Algonquin Provincial Park, Canada, demonstrate that males also exhibit an alternative, coercive mating strategy. Males are equipped with sexually size dimorphic tomiodonts, tooth-like cusps of the beak, as well as a weaponized anterior shell, with which they wound the head and neck of females. Behavioral trials during the breeding periods showed that male reproductive tactics shift from courtship (foreclaw display) to coercion (striking, biting, and forced submergence) across ontogeny, and male size predicts the occurrence and frequency of coercive behavior. We found phenotype-behavior matching whereby small males invest in putatively ornamental foreclaws used for courtship and large males invest in weaponry for coercion, challenging existing knowledge of this well-studied species. As a group with a long evolutionary history and varied mating systems, Testudines are a particularly interesting taxon in which to ask questions about mating system evolution. Significance statement: Alternative reproductive tactics are hypothesized for long-lived species. We quantified a shift from apparent courtship to coercive tactics during the reproductive lifespan of a well-studied freshwater turtle. Male painted turtles (Chrysemys picta) have sexual weapons that are used to promote female acquiescence. Using behavioral trials with turtles from a long-term study population, we demonstrate that males match their morphology (ornament/weapons) to reproductive behavior (courtship/coercion) as their reproductive tactics shift. Our findings hint at the behavioral complexity of aquatic turtles, a challenging and often-overlooked group in behavioral studies. [ABSTRACT FROM AUTHOR]

Ranaviruses have been associated with chelonian mortality. In Canada, the first two cases of ranavirus were detected in turtles in 2018 in Ontario, although a subsequent survey of its prevalence failed to detect additional positive cases. To confirm the prevalence of ranavirus in turtles in Ontario, we used a more sensitive method to investigate if lower level persistent infection was present in the population. Here we report results via a combination of qPCR, PCR, Sanger sequencing and genome sequencing from turtles from across Ontario, with no clinical signs of illness. We found 2 positives with high viral load and 5 positives with low viral load. Histopathology found subtle histological changes. DNA sequences identified two types of frog virus 3 (FV3), and genome sequencing identified a ranavirus similar to wild-type FV3. Our results show that the virus has been present in Ontario's turtles as subclinical infections. • Positives turtles with high and low viral load based on qPCR. • Evidence of subclinical infection. • Histopathology found subtle histological changes. • DNA sequences identified two types of frog virus 3. • Genome sequencing identified a ranavirus similar to wild-type FV3. [ABSTRACT FROM AUTHOR]

Long-term studies on wildlife populations are necessary to track population abundance and shifts in demography over time, yet such studies are difficult to plan, fund, and conduct and are therefore rarely undertaken. Such studies are especially important for long-lived species that can persist for long periods of time with little to no reproductive output or recruitment. We conducted two population studies spanning a 30-year time frame on the globally endangered Spotted Turtle (Clemmys guttata) on protected land in the center of their range. Spotted Turtles are endangered in Canada, listed as globally endangered on the IUCN red list, and declining throughout their range. However, there has only been one previous long-term study tracking their long-term population trajectory. Here, we use mark–recapture data collected over a 30-year time frame and report that the estimated population size of Spotted Turtles has decreased by 49% at our study site despite the habitat residing with a protected area. This decline was concurrent with a significant increase in the proportion of larger individuals within the population, indicating a lack of recruitment into the sub-adult stage class. These results highlight the value of long-term studies in monitoring population changes of long-lived species, the importance of active management within protected areas, and the ability of long-lived species to persist for long periods of time despite having little recruitment and a declining population trajectory. [ABSTRACT FROM AUTHOR]

Roads impact wildlife in a variety of direct and indirect ways. Roads may act as barriers to dispersal, lead to decreasing population size and genetic diversity, change animal behavior, result in direct mortality, and increase habitat disturbance. Road mortality is especially detrimental to long-lived species, such as freshwater turtles, whose population persistence relies on high adult and subadult survivorship to counter high egg and hatchling mortality. The Spotted Turtle (Clemmys guttata) is a small-bodied, freshwater turtle species that is listed as endangered in Canada and proposed for federal listing in the United States. We used a population viability analysis to attempt to quantify the impact that road mortality has on two distinct populations of Spotted Turtles. The baseline model for the North Wetland Complex (NWC) population predicted a probability of quasi-extinction within 150 yr of 20%. The baseline model for the South Wetland Complex (SWC) predicted a probability of quasi-extinction within 150 yr of 24%. Including an estimate of road mortality (modeled as a reduction in adult survival through annual catastrophic events) into the models, the probability of quasiextinction within 150 yr changed to 93% for the NWC and 94% for the SWC. Our results highlight the critical importance that anthropogenic additive adult mortality has on small populations of turtles and the necessity of detailed demographic studies to detect potential declines in populations of long-lived species. [ABSTRACT FROM AUTHOR]

Species at risk in Canada receive different levels of habitat protection depending on their status under the federal Species at Risk Act (e.g., Endangered or Threatened, vs. Special Concern). Accurate detection of species presence can facilitate appropriate habitat protection. For example, the Blanding's turtle (Emydoidea blandingii; Threatened, COSEWIC 2016) receives legislated habitat protection for its nesting sites on federal lands throughout its Canadian range, and on Crown and private lands in Ontario under the provincial Endangered Species Act. Nesting sites of the sympatric northern map turtle (Graptemys geographica; Special Concern, COSEWIC 2012) do not receive the same legislative protection. The eggs of these 2 species look very similar, making nest identification challenging. In this study we tested whether external egg morphology can reliably identify these species' eggs, using measurements from 13 Blanding's turtle clutches (143 eggs) and 72 northern map turtle clutches (873 eggs). Although the mean length, width and volume of eggs differed significantly between the species, strong overlap in the ranges of these measurements prevent reliable identification to species. Alternative methods for egg identification include incubation and identification of the hatchlings, scanning electron microscopy of eggshell fragments, or eDNA analysis of swabs taken from the surface of recently laid eggs. [ABSTRACT FROM AUTHOR]

We examined captures of Painted Turtle (Chrysemys picta) in Algonquin Provincial Park, Ontario, Canada, during the understudied summer-autumn transition period (August-September). The proportion of captured male turtles increased relative to the proportion of females during the late summer and early autumn sampling period, leading to male-biased capture rates in a population with a strongly female-biased sex ratio. We consider explanations for the capture bias in relation to sex-specific activity patterns and briefly discuss the implications of sampling period on the outcome of population structure studies. [ABSTRACT FROM AUTHOR]

Snapping Turtle (Chelydra serpentina) is native to mainland Nova Scotia, but its status on Cape Breton Island has been uncertain. Although it was recorded from Cape Breton Island as early as 1953, until 1984, it was known from only three widely scattered locations. Since that time, additional reports received from the public by Nova Scotia Department of Natural Resources and the Nova Scotia Museum of Natural History suggest that the species is native to Cape Breton Island. Thus, we are adding Snapping Turtle to the native herpetofauna of Cape Breton Island, Nova Scotia. [ABSTRACT FROM AUTHOR]

Based on current knowledge of the ecology and distribution of Snapping Turtle (Chelydra serpentina), both in eastern Canada and elsewhere, we conclude this species is native to Cape Breton Island. Seventy-two reports of Snapping Turtle from Cape Breton (1999-2017) indicate a range centred in the area south of Bras d'Or Lake. Date of oviposition ranged from 19 June to 10 July (median = 26 June) among 26 nests observed during 2012-2014. Clutch size for these nests was 23-65 eggs (mean = 46) and among 25 protected nests average rate of hatchling emergence was 21.5%. Time from oviposition to emergence of hatchlings (n = 256) was 75-120 days (mean = 87.2; SD = 9.0) among 20 nests. First emergence ranged from 9 September to 20 October (75-114 nest days; mean = 90) and last emergence ranged ftom 13 September to 28 October (86-120 nest days; mean = 100). Duration of emergence ranged from one day (i.e., synchronous emergence; five nests) to 37 days (mean = 11 days). The number of days on which hatchlings emerged at a nest ranged from one to nine days (mean = 4 days). Maximum carapace length was 25.0-31.8 mm (mean = 29.0 mm) and maximum carapace width was 23.5-30.0 mm (mean = 27.0 mm) for 256 hatchlings that emerged from 20 protected nests. Mass of hatchlings was 4.9-9.9 g (mean = 7.8 g). [ABSTRACT FROM AUTHOR]

The viability of freshwater turtle populations is largely dependent on the survivorship of reproducing females but females are frequently killed on roads as they move to nesting sites. Installing artificial nesting mounds may increase recruitment and decrease the risk of mortality for gravid females by enticing them to nest closer to aquatic habitats. We evaluated the effectiveness of artificial nesting mounds installed in Algonquin Park, Canada. Artificial mounds were monitored for 2 years to determine if turtles would select them for nest sites. We also simulated turtle paths from wetlands to nests to determine the probability that females would encounter the new habitat. A transplant experiment with clutches of Chrysemys picta and Chelydra serpentina eggs compared nest success and incubation conditions in the absence of predation between artificial mounds and natural sites. More turtles than expected used the artificial mounds, although mounds comprised a small proportion of the available nesting habitat and the simulations predicted that the probability of females encountering mounds was low. Hatching success was higher in nests transplanted to artificial mounds (93%) than in natural nests (56%), despite no differences in heat units. Greater use than expected, high hatching success, and healthy hatchlings emerging from nests in artificial mounds suggest promise for their use as conservation tools. [ABSTRACT FROM AUTHOR]

Sexual selection theory predicts that males should be promiscuous to maximize their reproductive success, while females should be choosy. Yet females of many taxa often produce progeny sired by multiple males, indicating that promiscuity can be important for the reproductive success of females. Promiscuity may enhance the fitness of females if it increases the genetic quality, or the genetic variety, and thus the viability of their offspring. We quantified the number of sires per clutch in a population of Northern Map Turtles ( Graptemys geographica (LeSueur, 1817)) in Lake Opinicon, Ontario, Canada, and tested whether the number of sires affects several metrics of viability in hatchlings. Based on the most conservative estimate, at least 71% of clutches in this population are sired by multiple males, but there was no evidence that larger clutches are sired by more males. Clutches sired by more males had higher hatching success and survival, but the differences were not statistically significant. We did not find any effect of the number of sires on hatchling morphology or locomotor performance. Collectively, our results partially support the hypothesis that promiscuity can increase the reproductive success of female Northern Map Turtles. [ABSTRACT FROM AUTHOR]

The "information age" ushered in an explosion of knowledge and access to knowledge that continues to revolutionize society. Knowledge about turtles, as measured by number of published papers, has been growing at an exponential rate since the early 1970s, a phenomenon mirrored in all scientific disciplines. Although knowledge about turtles, as measured by number of citations for papers in scientific journals, has been growing rapidly, this taxonomic group remains highly imperiled suggesting that knowledge is not always successfully translated into effective conservation of turtles. We reviewed the body of literature on turtles of the United States and Canada and found that: 1) the number of citations is biased toward large-bodied species, 2) the number of citations is biased toward wide-ranging species, and 3) conservation status has little effect on the accumulation of knowledge for a species, especially after removing the effects of body size or range size. The dispersion of knowledge, measured by Shannon Weiner diversity and evenness indices across species, was identical from 1994 to 2009 suggesting that poorly studied species remained poorly-studied species while well-studied species remained well studied. Several species listed as threatened or endangered under the U.S. Endangered Species Act (e.g., Pseudemys alabamensis, Sternotherus depressus, and Graptemys oculifera) remain poorly studied with the estimated number of citations for each ranging from only 13-24. The low number of citations for these species could best be explained by their restricted distribution and/or their smaller size. Despite the exponential increase in knowledge of turtles in the United States and Canada, no species of turtle listed under the Endangered Species Act has ever been delisted for reason of recovery. Therefore, increased knowledge does not necessarily contribute appreciably to recovery of threatened turtles. [ABSTRACT FROM AUTHOR]

Remotely sensed tracking technology has revealed remarkable migration patterns that were previously unknown; however, models to optimally use such data have developed more slowly. Here, we present a hierarchical Bayes state-space framework that allows us to combine tracking data from a collection of animals and make inferences at both individual and broader levels. We formulate models that allow the navigation ability of animals to be estimated and demonstrate how information can be combined over many animals to allow improved estimation. We also show how formal hypothesis testing regarding navigation ability can easily be accomplished in this framework. Using Argos satellite tracking data from 14 leatherback turtles, 7 males and 7 females, during their southward migration from Nova Scotia, Canada, we find that the circle of confusion (the radius around an animal's location within which it is unable to determine its location precisely) is approximately 96 km. This estimate suggests that the turtles' navigation does not need to be highly accurate, especially if they are able to use more reliable cues as they near their destination. Moreover, for the 14 turtles examined, there is little evidence to suggest that male and female navigation abilities differ. Because of the minimal assumptions made about the movement process, our approach can be used to estimate and compare navigation ability for many migratory species that are able to carry electronic tracking devices. [ABSTRACT FROM AUTHOR]

Understanding habitat use of declining species is essential for their management and successful recovery. We examined habitat selection at multiple spatial scales by Northern Map Turtles (Graptemys geographica (Le Sueur, 1817)), a species at risk, in the St. Lawrence Islands National Park, Ontario, Canada. At the scale of the home range, Map Turtles generally avoided deep water (>2 m) and selected home ranges in waters <1 m deep. Importantly, turtles used home ranges with significantly more natural than developed shoreline. At the scale of the location, adult females used deep water more often and males preferred areas with surface cover. Management efforts should implement regulations concerning further shoreline development. La gestion et la récupération réussie des espèces en déclin nécessitent une compréhension de leur utilisation de l'habitat. Nous examinons la sélection de l'habitat à plusieurs échelles spatiales chez la tortue géographique (Graptemys geographica (Le Sueur, 1817)), une espèce vulnérable, dans le parc national des Îles-du-Saint-Laurent, Ontario, Canada. À l'échelle du domaine vital, les tortues géographiques évitent généralement les eaux profondes (>2 m) et choisissent des domaines vitaux dans des eaux de <1 m de profondeur. Ce qui est plus important, les tortues utilisent des domaines vitaux qui possèdent significativement plus de ligne de rivage naturelle que modifiée. À l'échelle du site, les femelles adultes utilisent les eaux profondes plus fréquemment et les mâles préfèrent les zones qui possèdent un couvert en surface. Les efforts de gestion devraient inclure la mise en vigueur de règlements concernant les modifications futures des rivages. [ABSTRACT FROM AUTHOR]

The estimation and maintenance of connectivity among local populations is an important conservation goal for many species at risk. We used Bayesian statistics and coalescent theory to estimate short- and long-term directional gene flow among subpopulations for two reptiles that occur in Canada as peripheral populations that are geographically disjunct from the core of their respective species' ranges: the black ratsnake and the Blanding's turtle. Estimates of directional gene flow were used to examine population connectivity and potential genetic source-sink dynamics. For both species, our estimates of directional short- and long-term gene flow were consistently lower than estimates inferred previously from FST measures. Short- and long-term gene flow estimates were discordant in both species, suggesting that population dynamics have varied temporally in both species. These estimates of directional gene flow were used to identify specific subpopulations in both species that may be of high conservation value because they are net exporters of individuals to other subpopulations. Overall, our results show that the use of more sophisticated methods to evaluate population genetic data can provide valuable information for the conservation of species at risk, including bidirectional estimates of subpopulation connectivity that rely on fewer assumptions than more traditional analyses. Such information can be used by conservation practitioners to better understand the geographic scope required to maintain a functional metapopulation, determine which habitat corridors within a working landscape may be most important to maintain connectivity among subpopulations, and to prioritize subpopulations with respect to their potential to act as genetic sources within the metapopulation. [ABSTRACT FROM AUTHOR]

Northern ectotherms must seek refuge from winter conditions for a large portion of their annual activity cycle. The objective of this study was to quantify physical properties of overwintering sites selected by wood turtles (Glyptemys insculpta (LaConte, 1830)) at the species’ northern range limit. We mapped all structural features (e.g., root balls and log jams), water depth, and sediment types along a 1.5 km stretch of river that was available to turtles outfitted with radio transmitters (N = 8) during winter. Temperature selection was assessed by comparing thermal profiles from data loggers on turtles and temperature stations within the river and other riparian habitats (e.g., ephemeral pools and oxbows). Dissolved oxygen (DO) was measured at each temperature station and turtle location. Wood turtles overwintered in the river, which was colder (~0 °C), had more stable temperatures, and provided higher DO (12.64 ppm) compared with adjacent habitats. Some turtles selected structured refuges for overwintering. Winter movements were not related to temperature or DO, but may be related to maintaining a certain distance from shore and water depth to protect against accidental relocations during winter. We discuss hibernacula as potential factors limiting the northern distribution of wood turtles, a species at risk in Canada. Les ectothermes nordiques doivent trouver un refuge contre les conditions hivernales durant une partie importante de leur cycle annuel d’activités. L’objectif de notre étude est de mesurer les propriétés physiques des sites d’hivernage choisis par les tortues des bois (Glyptemys insculpta (LeConte, 1830)) à la limite boréale de la répartition de l’espèce. Nous avons cartographié tous les éléments structuraux (par ex., boules de racines et embâcles), la profondeur de l’eau et les types de sédiments sur une section de 1,5 km de rivière disponible à des tortues (N = 8) porteuses de radiotransmetteurs pendant l’hiver. La sélection de la température a été évaluée en comparant les profils de températures sur les enregistreuses fixées aux tortues et ceux des stations d’enregistrement dans la rivière et dans les autres habitats de la rive (par ex., les étangs temporaires et les bras morts). Nous avons mesuré l’oxygène dissous (DO) à chaque station d’enregistrement thermique et à chaque emplacement habité par une tortue. Les tortues des bois passent l’hiver dans la rivière qui présente des températures plus froides (~0 °C), mais plus stables et des concentrations de DO plus grandes (12,64 ppm) que les habitats adjacents. Quelques tortues ont choisi des refuges dans des structures pour passer l’hiver. Les déplacements en hiver ne sont pas reliés à la température, ni à la concentration de DO, mais s’expliquent peut-être par le besoin de maintenir une certaine distance de la berge et une certaine profondeur d’eau afin d’éviter les déplacements accidentels pendant l’hiver. Nous discutons des hibernacles comme facteurs potentiels qui peuvent limiter la répartition vers le nord de la tortue des bois, une espèce à risque au Canada. [ABSTRACT FROM AUTHOR]

Reptiles are in decline globally, and one-third of turtle species are considered endangered or vulnerable. Conservation of turtles presents special challenges, as turtles are long-lived, and have delayed sexual maturity, making long-term study necessary for accurate calculation of life history parameters. The spotted turtle (Clemmys guttata) is listed as an endangered species in Canada. A population in eastern Georgian Bay, Ontario has been the focus of the longest-running ecological study (30 years) on the species to date. The objective of the current project was to use the long-term demographic data to parameterize a stage-classified matrix and to use the model to asses several hypothetical management scenarios. Elasticity analyses and simulations indicated that small changes in adult survivorship would have the largest proportional effect on population growth rate, and that increasing survivorship of juveniles to 100% would result in the largest increase in population growth rate. Simulation of nest protection and headstarting scenarios indicated that these are inefficient conservation strategies for this species. We recommend that adults, and when possible, juveniles, be the stages targeted for conservation in spotted turtles and other long-lived iteroparous vertebrates. [Copyright &y& Elsevier]

Nineteen Blanding's turtles (Emydoidea blandingii), eight snapping turtles (Chelydra serpentina) and fourteen painted (Chrysemys picta) turtles trapped in Nova Scotia in 2005 were examined for epizoic algae. Algae were macroscopically apparent on 14 Blanding's and seven snapping turtles; microscopic examination of material scraped from various surfaces of these turtles revealed the predominance of two algal taxa. The cladophoroid green alga Basicladia chelonum was common on the shell of both Blanding's and snapping turtles and also present on the head and tail of the latter. B. chelonum is reported for the first time in Canada east of Ontario. A filamentous cyanobacterium, Komvophoron sp., formed extensive colonies solely in the leg bases of Blanding's turtles, where B. chelonum was absent. Although the nature of the interaction is unknown, this is the first potential symbiosis between a cyanobacterium and a turtle. Examination of a historical (2001-05) photographic database for Blanding's turtle in Nova Scotia revealed a colonization rate of 10% for B. chelonum and 46% for Komvophoron sp. It also revealed population and age-specific differences in frequency of the two algal taxa on Blanding's turtles. [ABSTRACT FROM AUTHOR]

Changes to population and community structure can have important ecological consequences and raise conservation concerns when causes are anthropogenic; however, signs of stress may not always be apparent. Turtles are long-lived and presence of adults may suggest healthy populations when lack of recruitment is actually threatening persistence. We observed and captured turtles for two years in Point Pelee National Park, Ontario, Canada, and compared our results with those collected 30 years earlier to determine if (1) species relative abundance, (2) sex ratios, and (3) age structure changed over three decades. Extirpation of the spotted turtle since 1972–1973 has altered the park’s species assemblage. Evidence also suggests that Blanding’s turtles have declined. Sex ratios were similar between time periods for all species except for the painted turtle which has become significantly more male-biased. Size structure for Blanding’s and snapping turtles shifted towards larger and presumably older age classes. Our results suggest that limited juvenile recruitment caused the size shift. Heavy predation on turtle nests from a dense raccoon population appears to be the main factor limiting recruitment. Despite protecting a sizable fragment of turtle habitat for a century, Point Pelee has lost one species and only one other species has a large healthy population. Our study illustrates that habitat protection provides no guarantee for species persistence when multiple threats exist and highlights the necessity for monitoring populations of long-lived species. [Copyright &y& Elsevier]

In North America, the spatio-temporal scale of deforestation has resulted in a 94% decrease in temperate forests within 360 years. Despite the enormous scale of this disturbance, agriculture is so pervasive in modern society that its impacts are highly underappreciated. We investigated the impact of current agricultural practices on a disturbance-dependent species in southern Québec, Canada. Of 30 wood turtles (Glyptemys insculpta) followed via radio-telemetry, 20% died as a result of agricultural activities. Anthropogenic mortality estimates for adults and juveniles in 1998 were 0. 10 and 0. 18, respectively. For 1999, these values were 0. 13 and 0. 17, respectively. Of those turtles that survived, many had injuries inflicted by agricultural machinery. Sub-lethal mutilation rates for adults were 90±3% in both years, whereas the maximum frequency for juveniles was 57%. A Carapace Mutilation Index was derived to quantify the distribution and severity of injuries observed. Only male and juvenile Carapace Mutilation Index values differed significantly. Adults had significantly more carapace injuries and limb amputations on their right sides. This bilateral asymmetry of injuries resulted from of a combination of turtle flight behavior and traditional harvesting practices. We reiterate the recommendations of forage researchers: setting the cutting height of disc mowers to 100mm increases harvest yields, reduces wear on machinery, and decreases soil erosion. A by-product of such a change in cutting height is that turtle mortality and injury rates should be reduced, as wood turtle carapace height is <87mm. Without changes in agricultural practices, this population will be extirpated. [Copyright &y& Elsevier]

Three turtles are present in a Turonian–Coniacian age high-latitude vertebrate assemblage from Axel Heiberg Island: Borealochelys axelheibergensis gen. et sp. nov., a generically indeterminate eucryptodire, and a trionychid. The assemblage differs from most Late Cretaceous turtle assemblages from North America in that members of the Paracryptodira are absent. The absence of this group is interpreted as a result of latitudinal differentiation of turtle assemblages in North America during the Late Cretaceous. The level of diversity of turtles in the Axel Heiberg assemblage is comparable to that of mid-latitude assemblages associated with a mean annual paleotemperature of 14 °C, adding to the evidence for high mean annual temperatures at high latitudes during Turonian–Coniacian times. [ABSTRACT FROM AUTHOR]

Like other terrestrial tortoises, the courtship behaviour of Hermann's tortoises (Testudo hermanni Gmelin, 1789) is based on a multiple signalling system that involves visual, olfactory, tactile, and acoustic signals. In this study, we analysed relationships between male morphology, hematological profile, courtship intensity, vocalizations, and mounting success in Hermann's tortoises breeding in semi-natural enclosures to investigate the effects of male condition on signals exhibited during courtship and on their mounting success. Results showed that mounting success of Hermann's tortoise males was positively affected by the number of sexual interactions/h, number of bites given to the female during interactions, and by call rate and frequency-modulation range. Call rate, frequency-modulation range, and number of sexual interaction/h increased with hematocrit value, while number of bites given to females decreased with leukocyte concentration. In conclusion, courtship signals exhibited by Hermann's tortoise males, including vocalizations, reliably reveal different components of male condition, and females may use these multiple traits to choose high-quality partners. This is the first study documenting the condition-dependent nature of tortoise courting signals and their effect on male mounting success. [ABSTRACT FROM AUTHOR]

The small tortoises of southern Africa include the only testudinid taxa that produce single-egg clutches. This group includes the world's smallest tortoise, Homopus signatus (Gmelin, 1789), which inhabits a harsh, arid environment. Climate and body size may influence reproductive output, so we hypothesized that the east–west aridity gradient in southern Africa affects egg and clutch size of the small indigenous tortoises, and that the morphology of H. signatus constrains egg size, preventing the formation of optimal eggs. Here we show that aridity and unpredictable rainfall determine which of these tortoise taxa produce single-egg clutches. Taxa in less predictable environments produce larger eggs relative to body size than do taxa in more predictable environments. Homopus signatus produces the largest egg relative to body size, probably to enhance offspring survival in its harsh environment. Body size, pelvic aperture size, and the narrow anal gap of H. signatus appear to constrain egg size. Despite these constraints, females produce rigid-shelled eggs larger than the pelvic canal and use pelvic kinesis to pass eggs at oviposition; both features are unknown in other chelonians and emphasize the selective advantage of large eggs to H. signatus. [ABSTRACT FROM AUTHOR]

The Green Turtle (Chelonia mydas) principally occupies tropical and subtropical waters, although juveniles are known to occur seasonally in temperate coastal waters. Collaboration with commercial fishers in eastern Canada yielded the most northerly records of this species in the northwest Atlantic. Here we report on the first confirmed record of a Green Turtle in eastern Canada and on the occurrence of a rare Green Turtle-Loggerhead Turtle (Caretta caretta) hybrid. Hybridization between the Carettini and Chelonini is extraordinary given that these groups have been genetically distinct for 50 million years or more. [ABSTRACT FROM AUTHOR]

Mark-recapture and radio telemetry data were collected from 1999-2001 on a population of Spotted Turtles, Clemmys guttata, near their northern limit in Ontario, Canada, and compared with a similar study conducted from 1983-1986. In 1999-2001, 32 Spotted Turtles were caught, 27 of which were adults. Females outnumbered males 3.5:1. The carapace length (CL) of adult males (108.5 ±5.7 mm) and adult females (106.4 ± 6.0 mm) did not differ significantly. A minimum of 22% of juveniles and 40% of adults marked in 1983-1984 were still alive in 1999-2001. Adult population size was estimated to be 45 (95% confidence interval: 34-78). Tile average size of individual adults marked in 1983 (105.6 ± 6.0 mm CL) and recaptured during 19992001 (106.3 ± 5.9 mm CL) did not differ significantly. There was also no significant difference in the number of growth lines on adults caught in 1983 (12.9 ± 2.0) and 1999 (14.0 ± 2.3). Based on the number of growth lines in 1983, these turtles averaged a minimum of 28.9 years in 1999, but actual ages are likely greater. Summer range length averaged 233 m (range: 200-275 m), while total range length averaged 327 m (range: 275-375 m). [ABSTRACT FROM AUTHOR]

The Wood Turtle, Glyptemys insculpta, population at River Denys, Inverness County, Cape Breton Island. Nova Scotia. was unknown except locally until listed in a provincial survey in 1995, Subsequently a hatchling was photographed at McLennan Brook on 17 September 1999, and three adult males were photographed between 14 and 19 September 2000. Two adult females were photographed at South Side River Denys on 18 June 2001. An excavated nest and empty egg shells were located at the same time on a stony-gravel bank at the outflow of McLennan Brook, and one sub-adult male was found at the edge of a hay field on 19 August 2001. Additional observations made of a nesting site and five basking sites, mostly along the main branch of River Denys, provide further evidence that a breeding population of Wood Turtles exists in River Denys watershed. [ABSTRACT FROM AUTHOR]

Provides information on a study that analyzed variation in the rapidly evolving mitochondrial control region in 241 turtles from 117 localities across North America from southern Canada to extreme northern Mexico to examine whether the painted turtle, Chrysemys picta represents a continentally distributed species based on molecular analysis. Methodology of the study; Results and discussion on the study.

A new fauna of fossil marine reptiles is described from the Late Cretaceous Nanaimo Group of Vancouver Island. The fossils are from the Haslam and Pender formations (upper Santonian) near Courtenay, British Columbia, and include elasmosaurid plesiosaurs, turtles, and mosasaurs. This is only the second fauna of Late Cretaceous marine reptiles known from the Pacific Coast, the other being from the Moreno Formation of California (Maastrichtian). The new Nanaimo Group fossils are some 15 million years older than those from the Moreno Formation. However, like the California fauna, there are no polycotylid plesiosaurs, and one of the mosasaurs is a new genus. This reinforces the provinciality of the Pacific faunas and their isolation from contemporaneous faunas in the Western Interior Seaway.Une nouvelle faune de reptiles marins est décrite en provenance du Groupe de Nanaimo (Crétacé tardif) de l'île de Vancouver. Les fossiles proviennent des formations de Haslam et de Pender (Santonien supérieur), près de Courtenay, en Colombie-Britannique et ils comprennent des plésiosaures Elasmosauridae, des tortues et des mosasaures. Cette faune est seulement la deuxième de reptiles marins du Crétacé tardif connue sur la côte du Pacifique, l'autre provenant de la Formation de Moreno (Maastrichtien) en Californie. Les nouveaux fossiles du Groupe de Nanaimo sont quelque 15 millions d'années plus âgés que ceux de la formation de Moreno. Toutefois, tout comme la faune de la Californie, il n'y a pas de plésiosaures Polycotylidae et l'un des mosasaures représente un nouveau genre. Cela donne du poids à l'idée de provincialisme des faunes du Pacifique et leur isolation des faunes contemporaines de la « Western Interior Seaway ».[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

We present morphological data on the four subspecies of painted turtles (Chrysemys picta) from 20 states in the U.S.A. and three provinces in Canada, and from localities within them that are removed from reported zones of intergradation. The characters used are those of Hartman (1958), which have been routinely used in subsequent studies: the extent of plastral patterning (here quantified by image analysis), the degree of misalignment of carapacial scutes, and the width of the light anterior margins of the second lateral scutes. Our purposes are to present descriptive baseline data for each subspecies for use in comparisons with the results of past and future studies of intergradation, and to critique the oft-accepted theory of Bleakney (1958) regarding the evolutionary origins of the current subspecies, particularly C. p. marginata. Data are given for C. p. bellii from 5 states ranging from Minnesota to New Mexico, for C. p. dorsalis from 3 states (Arkansas, Louisiana, and Mississippi), for C. p. marginata from 4 localities (Ontario, Michigan, Indiana, and Ohio), and for C. p. picta from 11 localities from Nova Scotia to Georgia. We find that (i) a "pure" picta does not exist; there is marginata influence throughout picta's range, particularly at the extremes; (ii) similarities exist that group dorsalis with picta; (iii) there is a north-south cline of reduced scute alignment in picta; (iv) there is a north-south cline of increasing extent of the plastral pattern in bellii; (v) the question of which subspecies first reached New England after the Wisconsinan glaciation remains unresolved, but it was likely not picta; (vi) there is no compelling reason to accept or reject Bleakney's theory of the distribution of painted turtle subspecies at the height of the Wisconsinan glaciation or his conjecture that marginata arose as in intergrade of bellii and dorsalis; in fact, it could be argued that if marginata is a hybrid, it could be a hybrid of picta and bellii.On trouvera ici des données morphologiques sur les quatre sous-espèces de Tortues peintes (Chrysemys picta) de 20 états (É.-U.) et trois provinces (Canada) et dans ceux-ci, de localités qui sont éloignées des zones connues d'intergradation. Les caractères choisis sont ceux de Hartman (1958) qui ont été utilisés couramment dans des recherches subséquentes : l'importance des dessins sur le plastron (quantifiée ici avec un analyseur d'images), le degré du désalignement des plaques de la carapace et la largeur des bordures antérieures claires des secondes plaques latérales. Nous nous proposons d'établir un système descriptif de base pour chaque sous-espèce de façon à faciliter les comparaisons avec d'autres travaux, passés ou futurs, sur l'intergradation et à faire le point sur la théorie souvent acceptée de Bleakney (1958) au sujet de origines évolutives des sous-espèces actuelles, particulièrement C. p. marginata. Les données concernent C. p. bellii de cinq états du Minnesota au Nouveau-Mexique, C. p. dorsalis de trois états (Arkansas, Louisiane et Mississippi), C. p. marginata de quatre localités (Ontario, Michigan, Indiana et Ohio) et Chrysemys picta picta de 11 localités, de la Nouvelle-Écosse à la Géorgie. Nous avons observé que (i) il n'existe pas de picta pur; l'influence de marginata se fait sentir dans toute la répartition de picta, particulièrement aux limites extrêmes; (ii) il y des similarités qui unissent dorsalis et picta; (iii) la réduction de l'alignement des plaques du bouclier chez picta suit un gradient nord-sud; (iv) l'augmentation de l'importance des dessins sur le plastron chez bellii suit également un gradient nord-sud; (v) la question à savoir quelle sous-espèce a atteint la Nouvelle-Angleterre la première après les glaciations du Wisconsinien n'est pas résolue, mais il est peu probable que ce soit picta; (vi) rien ne permet d'accepter ou de rejeter la théorie de Bleakney sur la répartition des sous-espèces au plus fort des glaciations du Wisconsinien ou son hypothèse selon laquelle marginata est apparue comme intergradation entre bellii et dorsalis; en fait, on pourrait argumenter que si marginata est un hybride, c'est un hybride de picta et de bellii.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Random amplified polymorphic DNA (RAPD) was used to compare the Nova Scotia population of Blanding’s turtle (Emydoidea blandingii) with several populations from the species’ main range. The Nova Scotia population is believed to have been isolated from the main range for 4000–8000 years. Cluster analysis using a neighbour-joining algorithm produced a dendrogram showing the Nova Scotia population clustering separately from those populations in the main range. Analysis of molecular variance shows 34.28% of total variance to be accounted for between the Nova Scotia population and populations in the main range. While this study is preliminary, the results suggest that the Nova Scotia population of Blanding’s turtle may be important to the maintenance of genetic diversity in the species. [ABSTRACT FROM AUTHOR]

End lines used in commercial trap/pot fishing pose a significant entanglement risk to whales, sea turtles, and sharks. Removal of these ropes for buoyless fishing is being considered by the United States and Canadian governments, but a method to systematically locate the gear without an attached buoy is required. A method was developed for an acoustic modem to self-localize and broadcast its location to nearby ships to minimize gear conflict, optimize power consumption, and reduce lost gear. This method was implemented using a research modem that self-localized to within 5 m of its estimated location on the sea floor.

The article features calendars with drawings and photographs of endangered reptiles in Canada. For 2004, black-and-white drawings of blue racer, black ratsnake, eastern foxsnake, stinkpot, wood turtle, prairie rattlesnake, and eastern ribbonsnake are included. These drawings were contributed by Joe Crowly, Kathryn Peiman, Mandi Eldridge, Kevin Kerr, Sonya Amin, Maris Bonofiglio, and Sarah Ingwerson. In the 2005 version, the drawings were replaced by colored photographs of seven snakes, six freshwater turtles, and a lizard.

During the period from 1994 to 1996, an increase in the number of laboratory-confirmed cases of human salmonellosis associated with exposure to exotic pets including iguanas, pet turtles, sugar gliders, and hedgehogs was observed in Canada. Pet turtle-associated salmonellosis was recognized as a serious public health problem in the 1960s and 1970s, and in February 1975 legislation banning the importation of turtles into Canada was enacted by Agriculture Canada. Reptile-associated salmonellosis is once again being recognized as a resurgent disease. From 1993 to 1995, there were more than 20,000 laboratory-confirmed human cases of salmonellosis in Canada. The major source of Salmonella infection is food; however, an estimated 3 to 5% of all cases of salmonellosis in humans are associated with exposure to exotic pets. Among the isolates from these patients with salmonellosis, a variety of Salmonella serotypes were also associated with exotic pets and included the following: S. java, S. stanley, S. poona, S. jangwani, S. tilene, S. litchfield, S. manhattan, S. pomona, S. miami, S. rubislaw, S. marina subsp. IV, and S. wassenaar subsp. IV.

The occurrence of Salmonella spp. in red-eared (Pseudemys scripta elegans) turtle eggs imported into Canada from Louisiana in June to September 1988 was examined. Of 28 lots tested, six (21%) lots from three of four exporters harbored salmonellae. Salmonella poona and Salmonella arizonae were frequently encountered in both fertile eggs and packaging moss. Turtles hatched in our laboratory from affected lots of eggs shed Salmonella in tank water for up to 11 months. Widespread use of gentamicin on turtle farms to produce Salmonella-free eggs for export apparently encouraged development of antibiotic resistance in bacterial strains. Of 37 Salmonella strains isolated in this study, 30 (81%) were gentamicin resistant. Such high levels of antibiotic-resistant salmonellae in turtle eggs pose a serious human health risk. Further marketing of turtle eggs and hatchlings should be curtailed until consistent production and distribution of Salmonella-free stocks can be assured.