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INTERACTIVE EFFECTS OF MALATHION EXPOSURE AND RANAVIRAL INFECTIONS IN WOOD FROGS (Rana sylvatica)

Amanda L. J. Duffus¹, Craig Brunetti², Bruce D. Pauli³ and Michael Berrill⁴.
¹Watershed Ecosystems Graduate Program, Trent University, Peterborough, ON. K9J 7B8. Tel: (705) 748 - 1011 ext. 1455, Fax: (705) 748 - 1205, email: [email protected]
²Department of Biology, Trent University, Peterborough, ON. K9J 7B8. Tel: (705) 748 - 1011 ext. 5151,Fax: (705) 748 - 1205, email: [email protected]
³Canadian Wildlife Service, National Wildlife Research Centre, Carleton University, Ottawa, K1A 0H3. Tel: (613) 998 - 6690, Fax: (613) 998 - 0458, email: [email protected]
⁴Department of Biology, Trent University, Peterborough, ON. K9J 7B8. Tel: (705) 748 - 1011 ext. 1455, Fax: (705) 748 - 1205, email: [email protected]

The interaction of stressors is becoming an important avenue of research permitting us to begin to understand how anthropogenic factors interact with naturally occurring stressors. Malathion is a common pesticide used to control mosquitoes and other insects in both urban and rural areas.

Malathion is also a known immunosuppressant. Ranaviruses are a group of emerging wildlife pathogens, of which Frog Virus 3 is a member, and are credited with contributing to the global decline of amphibians. In the wild, FV3 infections, on their own, cause a high mortality rate in wood frog tadpoles. This experiment examined the interaction between malathion exposure and induced infections of the emerging amphibian disease Frog Virus 3 (FV3) in wood frog (Rana sylvatica) tadpoles. Animals used in this experiment were bred in the lab from parents that were collected in terrestrial amplexus in the wild. Both of the parents tested negatively for the virus. The tadpoles were exposed to a consistent amount of the virus, which is known to cause infection in wood frog tadpoles, and two different levels of the pesticide in a controlled laboratory setting. It was found that the application of a combination of a high concentration of malathion and FV3 created symptomatic viral infections after only 24 hours post exposure/inoculation and the resulting FV3 infections were confirmed by PCR analysis. When the tadpoles were exposed to both malathion and FV3 the mortality rate increased, with the higher level of malathion exposure having the greatest mortality rates. With a lower concentration of malathion and FV3, mortality also increased. PCR was used to confirm the presence/absence of the virus in all trials. This study indicates that there is a synergistic or additive interaction between malathion exposure and FV3 infections. Thus, exposure to malathion increases tadpole susceptibility to FV3 infections.

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QUICK IDENTIFICATION OF Ambystoma HYBRIDS FROM THE JEFFERSON SALAMDER COMPLEX /IDENTIFICATION RAPIDE DES HYBRIDES Ambystoma DU COMPLEXE DE LA SALAMANDRE DE JEFFERSON

Jeanne Dumoulin¹, Sarah Noël¹, Martin Ouellet², Patrick Galois², and François-Joseph Lapointe¹
[email protected], [email protected], [email protected], [email protected], [email protected]
¹Département de Sciences Biologiques, Université de Montréal, C.P.6128, Succursale Centre-ville, Montréal, Québec, H3C 3J7, Canada (514) 343-6111 ext. 1031
²Amphibia-Nature, 4254 rue Garnier, Montréal, Québec, H2J 3R5, Canada, (514) 522-8105

Populations of unisexual salamanders of the genus Ambystoma can be found in eastern North America and are mainly composed of females. These unisexual salamanders arose from ancestral hybridization events, by incorporating the nuclear genomes of four bisexual species, and show different levels of ploidy. Although bisexual species are easily differentiated morphologically, hybrids can be difficult to discriminate visually because they may possess intermediate characters, or morphological traits from either of their diploid counterparts. Therefore, identification methods based on allozyme or chromosome data are often required to tell apart hybrids from bisexual species. In the present study, we introduce a novel way to discriminate between bisexual and unisexual salamanders based on species-specific primers designed in the mitochondrial cytochrome b region. This molecular approach provides a simple, rapid, non-invasive and efficient method, using a multiplex PCR and small tissue samples that can easily be obtained from live specimens. This method allows for a quick identification of hybrid populations. Because of their reproduction mode (parthenogenesis, gynogenesis or hybridogenesis), unisexual populations are more vulnerable to the loss of genetic diversity and are therefore more susceptible to local extinction if their habitat is fragmented or altered. It is thus of primary importance to identify hybrid populations to protect their habitat.

Les populations de salamandres unisexuées du genre Ambystoma se retrouvent dans l'Est de l'Amérique du Nord et sont principalement composées de femelles. Ces salamandres unisexuées qui proviennent d'hybridations ancestrales, ont incorporé le génome nucléaire de quatre espèces de salamandres bisexuées et présentent différentes combinaisons de ploïdie. Alors que les espèces bisexuées sont différenciées morphologiquement sans ambiguïté, les salamandres hybrides peuvent posséder certains caractères intermédiaires ou traits phénotypiques provenant de deux espèces parentales diploïdes et être difficiles à distinguer. En effet, des méthodes d'identification avec les allozymes ou les chromosomes sont souvent requises pour différencier les hybrides des espèces parentales. Dans la présente étude, nous introduisons une nouvelle méthode pour discriminer les salamandres unisexuées et bisexuées avec des amorces spécifiques, provenant de la région du Cytochrome b de l'ADN mitochondriale. Cette approche moléculaire est simple, rapide, non invasive et utilise une RPC en multiplex avec des petits échantillons de tissus pouvant provenir d'individus vivants. Cette méthode permet une identification rapide des populations hybrides. À cause de leur différents modes de reproduction (parthénogenèse, gynogenèse ou hybridogenèse), les populations de salamandres unisexuées sont plus vulnérables à la perte de diversité génétique et donc plus susceptibles à l'extinction locale si leur habitat est fragmenté ou altéré. Il est donc primordial de pouvoir identifier les populations hybrides afin de bien protéger leur habitat.

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IMPACTS OF POND CONNECTIVITY ON AMPHIBIAN LIFE STAGES AT DELTA MARSH, MANITOBA

Katarzyna A. Dyszy¹, Dr. Dale Wrubleski², Dr. John Spence^3
1Dept of Renewable Resources, University of Alberta, Edmonton, Alberta, Email: [email protected] , Mailing address: 638 Warsaw Avenue, Winnipeg Manitoba, R3M 1C6, Tel: (w) 204-474-8469 (h) 204-474-2749
²Institute for Wetland and Waterfowl Research, Ducks Unlimited Canada, Stonewall, Manitoba, Email: [email protected], Mailing address: P.O Box 1160, Stonewall, Manitoba, R0C 2Z0
³Dept of Renewable Resources, University of Alberta, Edmonton, Alberta, Email: [email protected], Mailing address: 751 General Services Bldg, Universiy of Alberta, Edmonton, Alberta, T6G 2H5

Delta Marsh, located on the south shore of Lake Manitoba, is home to several anuran species that use the area extensively as breeding and summering grounds. Over the past 40 years, the introduction of common carp (Cyprinus carpio) and water level stabilization have contributed to the deterioration of those ponds connected to the main marsh while ponds isolated from the main marsh have not undergone such changes. To study the impact of pond connectivity on anuran populations, three anuran life stages were examined at Delta Marsh. Pond connectivity may play a key role in both breeding site selection and survival of anuran eggs. This data is supported with observations of reduced abundances of anuran breeding choruses and egg masses in connected sites when compared with isolated sites. Connected sites also had greater physical disturbance of artificial egg masses, suggesting where egg masses are oviposited at these sites, compounded effects from physical damage, such as from spawning common carp found exclusively at connected sites, further reduces egg mass numbers. Tadpole abundance, growth and rate of development was also examined with respect to pond connectivity, and found lower abundances of tadpoles in connected sites compared with isolated sites.

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THE EFFECT OF THE CONFIGURATION OF HABITAT RELATIVE TO ROADS ON POND-DWELLING AMPHIBIANS

Felix Eigenbrod¹, S.J. Hecnar², and L. Fahrig^1
1Geomatics and Landscape Ecology Research Laboratory (GLEL), Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, Canada K1S 5B6 Tel: 613-520-2600 ext 3831 Fax: (613) 520-3539
²Department of Biology, Lakehead University, 955 Oliver Rd, Thunder Bay, Ontario, Canada P7B 5E1 Tel: (807) 343-8250 Fax (807) 346-7796
Email addresses of authors: [email protected], [email protected], [email protected]

Two landscape variables have been found to be particularly important in predicting the species richness of pond-dwelling amphibians - the amount of natural habitat (forest and wetlands) and the density of paved roads present in the landscape. Many amphibians require secondary upland habitat (usually forest), and all benefit from additional breeding habitat in the landscape (wetlands and water bodies) to allow re-colonization of breeding ponds, whereas the main effect of roads is thought to be direct mortality. However, it seems likely that a road that needs to be crossed to access secondary habitat or other wetlands has a much greater negative effect than one that does not. In other words, the configuration of natural habitat relative to roads is likely very important. This is not directly measured by either habitat amount or road density. We hypothesized that the amount of natural habitat that is accessible from a breeding pond without crossing a paved road (accessible habitat amount) will be a better predictor of amphibian species richness than the combined effects of habitat amount and road density. We tested this hypothesis by looking at 30 pond dataset of species richness data. We found some evidence that accessible habitat was a better predictor of amphibian species richness than the combined effect of total habitat and road density at the 500m and 600m scale. However, above the 600m scale, total habitat and road density were highly correlated, making it impossible to tell from this dataset whether the results we found at 500m and 600m hold at higher spatial scales. While further studies are clearly needed, these results suggest that accessible habitat amount may be the best way to look at the combined effects of roads and habitat loss.

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DEMOGRAPHY AND BEHAVIOUR OF A GEORGIAN BAY POPULATION OF THE SPOTTED TURTLE (Clemmys guttata)

Jean Enneson, Jacqueline D. Litzgus
Department of Biology, Laurentian University, Sudbury, ON P3E 2C6, Telephone: (705) 675-1151 ext. 2314, Fax: 705-675-4859, Email: [email protected], [email protected]

The spotted turtle is listed as Vulnerable by the IUCN, Endangered in Canada, and Vulnerable in Ontario. An island in eastern Georgian Bay is the site of the longest-running mark-recapture study to date of the spotted turtle. Data collection has been carried out since 1977, for a total of 27 years of study. The purpose of the current study is to continue the long-term mark-recapture study to allow examination of life history, demographic, and population size changes. From May to August of 2005, known breeding aggregations were surveyed for spotted turtles. All turtles were marked if new, measured, weighed, sexed, injuries noted, and released. Palpation was used to determine if females were gravid and X-rays were used to determine clutch size. Ten turtles were outfitted with radio transmitters, and their movements monitored using GPS. A total of 33 turtles were captured in 2005; 42.4% were females, 39.4% were males, and 18.2% were juveniles. 66.7% of female turtles captured between breeding season and nesting season were gravid (N=9). All X-rayed gravid turtles (N=3) had clutch sizes of 6 eggs. Two radio-tracked turtles nested on a neighbouring island, which was not previously known to be a spotted turtle nesting site. The data collected from this ongoing study will allow determination of individual survivorship, population size, and aspects of population demography, which will be applied in population viability analyses. Ongoing radio-tracking will provide data to allow accurate calculation of home-range size. These data will be also used to examine critical habitat shifts and breeding behaviour responses by spotted turtles to natural habitat modification (caused by beaver damming) of a primary breeding aggregation site on the island.

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LANDSCAPE AND LOCAL FACTORS ASSOCIATED WITH VERTEBRATE ROADKILL IN SOUTHERN ONTARIO

Bob Farmer and Ron J. Brooks
Department of Integrative Biology, University of Guelph, 519-824-4120 ex. 58360, Fax 519-767-1656, [email protected], [email protected]

From mid-May until mid-October, I am surveying roads for vertebrate roadkill in the greater-park areas of Rondeau Provincial Park and Point Pelee National Park . By considering a variety of broad-scale and local variables, including landscape type, road density, road type, embankment slope, shoulder type, shoulder width, road curvature, road temperature, traffic volume, weather, time of day and season, this research will identify important determinants of roadkill for both individual and groups of species. Results will guide mitigation strategies and future construction by identifying road designs, locations and times associated with the highest collision risk.

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ASSESSING DNA DAMAGE IN FROGS FROM AGRICULTURAL AREAS OF SOUTHWESTERN ONTARIO, CANADA

Robyn M. Ferguson¹, Bruce D. Pauli¹, Pamela A. Martin², Tana V. McDaniel² , Chris Marvin³, Loren D. Knopper^4
1National Wildlife Research Centre, Canadian Wildlife Service, Environment Canada, Ottawa, ON, K1A 0H3
²Canadian Wildlife Service, Environment Canada, Burlington, ON, L7R 4A6
³National Water Research Institute, Environment Canada, Burlington, ON, L7R 4A6
⁴Jacques Whitford, Ottawa, ON, K1B 1A7

Genotoxicity in wildlife species as a result of non-target pesticide exposure has been reported in numerous studies. We examined whether field exposure to agricultural chemicals might result in measurable DNA damage in ranid amphibians inhabiting areas of intensive corn-soybean agriculture. To accomplish this we measured DNA damage in Rana pipiens (Northern leopard frogs) and Rana clamitans (Green frogs) collected in agricultural ponds and drainage ditches in southwestern Ontario. Blood from 72 adult frogs was collected between July and October, 2004, from 11 different sites: two control sites (without agricultural influence), one "agricultural control" site (marsh located within an agricultural area), and eight agricultural sites. Whole blood was diluted in a cryopreservant and flash frozen in vapor phase nitrogen and subsequently stored at -80(C. At a later date, blood was thawed and DNA damage (single and double DNA strand breaks) was assessed using the alkaline Comet assay. Water collected at the same sites as the frogs had measurable levels of atrazine, metolachlor, nutrients, and heavy metals in the agricultural and agricultural control sites, whereas these contaminants were very low or not detected in control sites. Because of this shared contamination, agricultural and agricultural control data were pooled and compared to control data. Measures of DNA damage using the Comet assay (tail length, % DNA in the tail) in frogs from agricultural sites was significantly greater than in frogs from control sites (p = 0.046, 0.08). The specific cause of the observed genotoxic damage is not known but our results suggest that frogs living in agricultural areas are exposed to genotoxins.

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CHRONIC EFFECTS OF ATRAZINE HERBICIDE ON THE DEVELOPMENT OF NORTHERN LEOPARD FROG (Rana pipiens) TADPOLES

Christina M. Fridgen¹, Bruce D. Pauli², Michael Berrill¹, Kenneth Doe³ and Paula Jackman^3
1Trent University Biology, Symons Campus 1600 West Bank Road, Peterborough Ontario Canada K9J 7B8, [email protected]
²Canadian Wildlife Service Ottawa Ontario
³Environment Canada Moncton New Brunswick

Amphibians are excellent model organisms in which to observe chronic effects of contaminants. They are particularly useful to examine effects of contaminants on the thyroid and gonadal axes, because of their endocrine-mediated differentiation processes such as metamorphosis and gonadal development. Exposure of amphibians to the popular corn herbicide atrazine has been associated with abnormal development of exposed frogs, particularly demasculinization and feminization, through a proposed mechanism of induced aromatase activity levels increasing conversion of androgens to estrogens. We conducted a blinded study examining the effects of chronic atrazine exposure (0.1 and 1.8 �g/L as Aatrex Liquid 480) on the development of Northern Leopard Frog Rana pipiens tadpoles. Animals were exposed from the egg stage to metamorphosis. Our main objectives were to compare our results with existing data, provide information concerning sensitive stages and endpoints in Ranid amphibians, and investigate new histological methods to quantify and stage early gonad differentiation in R. pipiens. Atrazine exposure caused significant chronic effects on both the growth and development of tadpoles and their gonads at concentrations as low as 0.1 �g/L. Preliminary statistical analyses indicate that Gosner Stage 25 to 40 tadpoles exposed to the lowest concentration tested have significantly increased body length and mass, as well as an increased average stage of development over time, yet significantly fewer tadpoles being reared in both test concentrations reached metamorphic climax at test termination. Both atrazine concentrations induced significantly larger female gonads, increasing both the ovary length and area. In addition, preliminary histology has revealed signs of intersex, testes with large primary oocytes, and ovaries with areas of abnormal somatic tissue. Further in-depth histological analysis of gonads to examine the influence of atrazine exposure on oocyte size, gonadal differentiation rate and stages, as well as intersex incidence is being conducted.

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THE RELATIVE EFFECTS OF FORESTED, AGRICULTURAL AND URBAN LANDSCAPES ON AMPHIBIAN COMMUNITIES IN EASTERN ONTARIO

Sara A. Gagné and L. Fahrig
Geomatics and Landscape Ecology Research Laboratory, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6

Since the early 1990s, evidence has been accumulating of the impact of landscape composition on amphibian species richness and abundance. The present study seeks to determine the relative effects of forested, agricultural and urban landscapes on anuran species richness and abundance in eastern Ontario. Six evening call surveys were conducted between April and June 2004 to assess anuran species richness and abundance at ponds surrounded by > 50% forest cover (9 ponds), > 70% open cover (10 ponds), and > 50% urban cover (11 ponds) within 1.5 km radius landscapes. Vegetation and water quality surveys were also conducted at each pond in June 2004 to measure local variables likely to affect anuran diversity. Preliminary results indicate that anuran species richness is significantly higher in forested and agricultural ponds than in urban ponds. Pond perimeter has also been identified as a significant positive predictor of anuran species richness. The effects of forested, agricultural and urban landscapes on the abundance of individual amphibian species will also be discussed.

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ASSESSING PREVALENCE OF CHYTRID FUNGUS (Batrachochytrium dendrobatidis) IN NATIVE AMPHIBIANS AND BULLFROGS (Rana catesbeiana) ON VANCOUVER ISLAND, BRITISH COLUMBIA /L'ÉVALUATION DE LA PRÉDOMINANCE DU MYCÈTE DE CHYTRID (Batrachochytrium dendrobatidis) DANS LES AMPHIBIES INDIGÈNE ET LES OUAOUARONS (Rana catesbeiana) SUR L'ÎLE DE VANCOUVER, COLOMBIE BRITANNIQUE

Purnima P. Govindarajulu¹, Trenton W. J. Garner² and Bradley R. Anholt^1
1Department of Biology, University of Victoria PO Box 3020 STN CSC Victoria, BC V8W 3N5, Canada Tel: (250) 383 6262 Fax: (250) 721 7120 Email: [email protected]
²Institute of Zoology, Zoological Society of London Regent's Park, London NW1 4RY U.K. Tel: 011 44 (0)20 7449 6687 Email: [email protected]
Bradley R. Anholt Department of Biology, University of Victoria PO Box 3020 STN CSC Victoria, BC V8W 3N5, Canada Tel: (250) 721 7106 Fax: (250) 721 7120 Email: [email protected]

Emerging wildlife diseases are increasingly recognized as a great threat to global biodiversity. Recently, the amphibian chytrid fungus (Batrachochytrium dendrobatidis) has been implicated in catastrophic declines of amphibians in Europe, North America, Central and South America, and Australia. In British Columbia, the distribution and level of prevalence of the chytrid fungus is poorly known. Important vectors of introduction and dispersal are thought to be to be commercially traded amphibians such as the African clawed frog (Xenopus laevis) and the American bullfrog (Rana catesbeiana). American bullfrogs have been widely introduced in the southwestern part of British Columbia and are expanding their range. In the summer of 2005, we sampled native amphibians and bullfrogs in four bullfrog and four bullfrog-free sites on southeastern Vancouver Island. Sensitive molecular techniques will be used to detect presence of the fungus from tissue samples of both the aquatic and terestrial life-stages. Up to date results from this ongoing study will be presented. This study will enable us to quantify the level of prevalence of chytrid fungus in free-ranging bullfrog populations. The level of prevalence of chytrid fungus in the non-bullfrog sites will be used to assess background levels of infection in native amphibians. Comparison of levels of prevalence of chytrid fungus in bullfrog vs. bullfrog-free sites will enable us to assess whether introduced bullfrogs were acting as vectors of spread of the disease.

Les nouvelles maladies de faune sont de plus en plus identifiées comme une des grandes menaces pour la biodiversité globale. Récemment, le mycète amphibie de chytrid (Batrachochytrium dendrobatidis) a été impliqué dans des déclins catastrophiques des amphibies en Europe, l'Amérique du nord, L'Amérique Centrale et Sud, et l'Australie. En Colombie Britannique, la distribution et le niveau de la prédominance du mycète de chytrid est peu connue. Des vecteurs importants de l'introduction et de la dispersion sont considerés d'être les amphibiens commercés tels que Xenopus laevis et les ouaouarons (Rana catesbeiana). Les ouaouarons ont été introduits en grand nombre au sud-ouest de Colombie Britannique et ils sont en train d'augmenter leur domaine. En été de 2005, nous avons prélevé les amphibiens indigènes et les ouaouarons dans quatre emplacements avec les ouaouarons, et les amphibiens indigènes dans quatre emplacement sans ouaouarons dans le sud-est de l'île de Vancouver. Des techniques moléculaires précises seront employées pour détecter la présence du mycète dans les échantillons de tissu tirés des specimens d'étapes aquatiques et terrestres. Les résultats le plus courant de cette étude continuelle seront presentés. Cette étude nous permettra de mesurer la fréquence du mycète de chytrid dans les populations des ouaouarons libres en Colombie Britannique. La frequence du mycète de chytrid dans les emplacements sans ouaouarons sera employé pour évaluer le niveau de reference de l'infection dans des amphibiens indigènes. La comparaison de la frequence du mycète de chytrid dans les emplacements avec ouaouarons par rapport aux emplacements sans ouaouarons nous permettra d'évaluer si les ouaouarons sont les vecteurs de la diffusion du mycète de chytrid.

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EFFECTS OF SEXUAL SIZE DIMORPHISM ON DIET SPECIALIZATION IN THE COMMON MAP TURTLE (Graptemys geographica)

Marie-Ange Gravel¹, Gregory Bulté², Gabriel Blouin-Demers³
Département de biologie - Department of Biology, Université d'Ottawa - University of Ottawa, 150 Louis Pasteur, Ottawa (Ontario) K1N 6N5 Canada, T: (613) 562-5800, F: (613) 562-5486, ¹ [email protected] , ² [email protected] , ³ [email protected]

Sexual size dimorphism may arise from sexual selection where one sex gains a reproductive advantage from being larger, or natural selection such as diet divergence, or both. In the Common Map Turtle (Graptemys geographica), females are much larger than males, often exceeding twice their size. Extreme female-biased sexual size dimorphism had been hypothesized to be a result of natural selection for diet divergence. The goal of our study is to test the hypothesis that male and female map turtles specialize on different prey. We assessed prey availability in our study lake (Lake Opinicon, Queen's University Biological Station). We collected fecal samples of adult and juvenile turtles of both sexes. Prey size can be reconstructed from mussel septa length and snail opercula length that are passed with the feces. The two sexes appear to be choosing different prey, as well as different prey size. Large females prey mostly on zebra mussels and snails (Viviparous georgianus), while juvenile females and males seem to consume smaller snails, small zebra mussels and caddisfly larva (Tricoptera). Also prey size seems to increase with body size within each sex.

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POPULATION DYNAMICS OF THE WOOD TURTLE IN THE GREATER KOUCHIBOUGUAC ECOSYSTEM, NEW BRUNSWICK / DYNAMIQUE DES POPULATIONS DE TORTUES DES BOIS DANS LE GRAND ÉCOSYSTÈME DE KOUCHIBOUGUAC, NOUVEAU-BRUNSWICK

Mireille Gravel¹, Éric Tremblay², Tom Herman³, and Donald McAlpine^4
1Kouchibouguac National Park of Canada, New Brunswick, E4X 2P1, Canada / Phone number: (506) 876-2443 / Fax number: (506) 876-4802 / Email address: HYPERLINK "mailto:[email protected]" [email protected]
²Kouchibouguac National Park of Canada, New Brunswick, E4X 2P1, Canada / Phone number: (506) 876-2443 / Fax number: (506) 876-4802 / Email address: HYPERLINK "mailto:é[email protected]" é[email protected]
³Biology department, Acadia University, Nova Scotia B4P 2R6, Canada / Phone number: (902) 585- 1469 / Fax number: (902) 585-1059 / Email address: HYPERLINK "mailto:[email protected]" [email protected]
⁴New Brunswick Museum, New Brunswick, E2K 1E5, Canada / Phone number: (506) 643-2345 / Fax number: (506) 643-2360 / Email address: HYPERLINK "mailto:[email protected]" [email protected]

The wood turtle and its habitat suffer important threats, linked predominantly to human activity like major deforestation, habitat fragmentation, growing tourism and road kills, all clearly present in New Brunswick. Nevertheless, only minimal protection has been accorded in Maritime Provinces. This turtle is widely spread in New Brunswick but of unknown abundance since no formal surveys have been undertaken. Aware of the presence of this designated "species of special concern" reptile in Kouchibouguac National Park and its Greater Ecosystem, it becomes crucial to act quickly by assessing the population. The specific objectives of this project are to 1) create a preliminary map of susceptible wood turtle habitat, 2) estimate the population density, 3) investigate movements, home range and habitat selectivity and 4) elucidate reproduction events in time and space (e.g. nesting, hatching). This project began in June 2005 and therefore, results remain preliminary. Most riparian habitats in the region, potentially suitable for wood turtles, have been monitored. Although we cannot yet estimate population densities, we are currently following 5 individuals by telemetry throughout the region, most likely belonging to 4 different populations. The location of hibernating sites of these turtles will allow us to find more individuals next year and to start earlier to record reproduction events as well. By informing and implying local communities to the project, we passed from 9 wood turtle sightings to 38 for the area and we plan on maintaining this collaboration through the years.

Des perturbations majeures affectant la tortue des bois et son habitat telles que la déforestation, la fragmentation de l'habitat, le tourisme grandissant et la mortalité sur la route, sont toutes clairement présentes au Nouveau-Brunswick. Toutefois, les mesures de protection accordées à l'espèce dans les provinces maritimes demeurent minimales. Bien que cette tortue soit largement répandue au Nouveau-Brunswick, son abondance n'est pas connue puisque aucun suivi n'a été fait dans la région jusqu'à ce jour. En sachant que ce reptile, désigné "espèce préoccupante", est présent dans le Grand Écosystème de Kouchibouguac, il est impératif d'agir rapidement en inventoriant les populations. Les objectifs spécifiques de ce projet sont de 1) créer une carte préliminaire d'habitats potentiels, 2) estimer la densité des populations, 3) suivre les mouvements afin de déterminer le domaine vital et la sélectivité d'habitats et 4) identifier les événements reliés à la reproduction temporellement et spatialement (ex. nidification, éclosion). Comme le projet a débuté en juin 2005, les résultats demeurent préliminaires. Nous avons visité la majorité des habitats rivulaires de la région afin de déterminer la présence d'habitats potentiels pour l'espèce. Quoiqu'il soit encore impossible d'estimer la densité des populations, nous suivons 5 individus par télémétrie dans l'aire d'étude, appartenant possiblement à 4 populations distinctes. La localisation des sites d'hibernations de ces tortues nous permettra de trouver plus d'individus l'an prochain ainsi qu'a suivre dès avril 2006 les événements reliés à la reproduction. En informant et en impliquant les communautés locales, nous sommes passé de 9 observations de tortues des bois à 38 dans la région et nous prévoyons entretenir cette précieuse collaboration tout au long de ce projet.

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PAVED ROADS AS BARRIERS TO AMPHIBIAN MOVEMENTS / LES ROUTES ASPHALTÉES: UNE BARRIÈRE AUX MOUVEMENTS D'AMPHIBIENS?

Mireille Gravel¹, Marc J. Mazerolle² and Marc-André Villard^3
1Canada Research Chair in Landscape Conservation, Département de biologie, Université de Moncton, Moncton, New Brunswick E1A 3E9, Canada. / Phone number : (506) 858-4869 / Fax number : (506) 858-4541 / Email address : [email protected]
²USGS Patuxent Wildlife Research Center, Laurel, MD 20708-4017 USA / Phone number: (301) 497-5636 / Fax number: (301) 497-5545 / Email address: [email protected]
³Canada Research Chair in Landscape Conservation, Département de biologie, Université de Moncton, Moncton, New Brunswick E1A 3E9, Canada. / Phone number: (506) 858-4334 / Fax number: (506) 858-4541 / Email address : [email protected]

We investigated whether paved roads acted as barriers to amphibian movements in the vicinity of 16 roadside ponds of southeastern New Brunswick, Canada. Our study was conducted over two successive summers (April-September), and focussed on three species groups: mole salamanders, toads, and ranid frogs. Using pitfall traps and drift fences placed on each side of the pond (i.e., one fence was separated from the pond by the road, the other was in continuous habitat, we examined the effects of roads, on 1) roadside adult and juvenile amphibian abundance and 2) movements across the road. We measured a number of road-associated variables such as traffic intensity, road proximity to the pond, and terrestrial habitat structure as well as others potentially influencing movements (e.g., pond size, hydroperiod). Despite considerable variation among groups, the abundance of juveniles and adults of each group was generally negatively influenced by road-associated variables for at least one of the study years. The proportion of juveniles dispersing from the pond was lowest at the roadside fence. In contrast, adult movements from the pond were highest at the roadside fence under high traffic intensities. Our results strongly suggest a barrier effect of paved roads on adult and juvenile amphibians even under low traffic densities and relatively low roadside habitat disturbances. This provides empirical evidence for deleterious effects of roads on amphibian populations and highlights the importance of accounting for roads in amphibian management.

Nous avons étudié l'effet des routes asphaltées comme potentielles barrières aux mouvements d'amphibiens en bordure de 16 étangs le long de routes dans le sud-est du Nouveau-Brunswick, Canada. Notre étude s'est déroulée pendant deux étés consécutifs (avril-septembre) et a ciblé trois groupes d'espèces: les salamandres, les crapauds et les grenouilles. En utilisant des pièges-fosses et des clôtures de dérive disposées de part et d'autre de l'étang (i.e., une clôture séparée de l'étang par une route, l'autre dans de l'habitat continu), nous avons examiné les effets de la route sur 1) l'abondance d'amphibiens adultes et juvéniles en bordure de route ainsi que 2) les déplacements impliquant une traversée de la route. Nous avons mesuré différentes variables associées à la route telles que l'intensité du trafic, la distance de la route à l'étang, la structure de l'habitat terrestre ainsi que d'autres facteurs pouvant influencer les mouvements (e.g., taille de l'étang, hydropériode). Malgré les variations considérables entre les groupes, l'abondance de juvéniles et d'adultes de différents groupes d'espèces était généralement influencée négativement par les variables associées à la route, et ce, pour au moins une des deux années de l'étude. La proportion de juvéniles en dispersion était plus faible à la clôture en bordure de la route qu'à celle située du côté de l'étang. Les mouvements des adultes étaient, au contraire, plus fréquents à la clôture en bordure de la route sur les sites ayant une grande intensité de trafic. Nos résultats suggèrent fortement un effet de barrière des routes asphaltées sur les mouvements d'amphibiens, même à faible intensité de trafic et faibles perturbations de l'habitat en bordure des routes. Cette étude fournit donc une preuve empirique des effets néfastes des routes sur les populations d'amphibiens et souligne l'importance de considérer les routes dans de futurs plans de gestion de ce taxon.

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THERMAL ECOLOGY OF OVERWINTERING WOOD TURTLES (Glyptemys insculpta) AT THE SPECIES' NORTHERN RANGE LIMIT

William F. Greaves and Jacqueline D. Litzgus
Laurentian University, Department of Biology, Sudbury, ON, P3E 2C6, Canada, Phone 705-670-1063, Fax: 705-675-4859, [email protected], [email protected]

Seasonal variation in activity patterns of reptiles is accompanied by physiological and behavioural adjustments that influence both their ecology and life history. Over-winter survival is an important factor limiting a species' northern range extension. A northern population of wood turtles (Glyptemys insculpta) in the Sudbury District, Ontario was surveyed in fall 2004 and a subset of adults (N = 5) radio-tracked during the winter of 2004-2005 to examine thermal aspects of hibernation. We tested the hypothesis that hibernation sites that provide protection from freezing and predation are a limited resource in the north, thus requiring turtles to use communal hibernacula. Temperature data loggers indicated that turtle body temperatures and hibernacula temperatures remained relatively stable at -0.5�C from 2 December 2004 until 3 April 2005. During the same period, air temperature was highly variable, ranging between -40�C and 11�C (average air temperature = -9.9�C). Turtles did not use distinct structures (e.g., root hollows, logjams, and holes in the riverbank) that would protect from predation during hibernation, but instead rested relatively exposed on the riverbed at a water depth of approximately 1m and at a mean distance of 0.99 m from the riverbank. Surprisingly, turtles made small movements during winter, typically against the river current and in a direction parallel to the riverbank. Average winter home range size was 4.40 m2. These findings contribute to a better understanding of the over-wintering ecology and thermal tolerances of G. insculpta at its northern limit, and are especially important because G. insculpta is declining in numbers, and is particularly vulnerable to increases in adult mortality (that may occur during hibernation) as a result of its bet-hedging life history.

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THE FOWLER'S TOAD RECOVERY PLAN

David M. Green¹ and Anne Yagi^2
1Redpath Museum, McGill University, 859 Sherbrooke St. W., Montreal, Quebec H3A 2K6. tel: (514) 398-4086 ext 4088. fax: (514) 398-3185. email: [email protected]
²Ministry of Natural Resources-Niagara Area Office, 4890 Victoria Ave. North, Box 5000, Vineland Station, Ontario, L0R 2E0. tel: 905-562-1196. fax: 905-562-1154. email: [email protected]

Although widespread throughout the eastern United States, Fowler's toad (Bufo fowleri) is restricted in Canada to sandy or rocky points and beaches along the northern shore of Lake Erie in Ontario. Viable populations are known from only three localities immediately adjacent to the lake: Rondeau, Long Point, and the Niagara peninsula. Assessed as "Threatened" by COSEWIC in 2000, Fowler's Toad has been legally listed under the Species at Risk Act as of 2003. Primary identified threats to the well-being of Fowler's toads in Canada include shoreline development and stabilization. Limiting factors include the animals' high mortality and short life span as well as the instability of its preferred shoreline habitats. Population size fluctuations and variable connectivity between required habitats also affect population survival. With these and other considerations in mind, the Fowler's Toad Recovery Team has crafted a recovery plan for the species based on assessment of population viability. In rank order, recruitment of juveniles into the adult population, population number, dispersal survival and, finally, adult survival are identified as the major factors affecting viability of Fowler's toad populations and, consequently, are the major components addressed in the recovery plan. The heart of the plan is contained under the headings "Not Worse (Conservation)", "Know More (Research)" and "Make Better (Amelioration and Recovery)". Outreaches to stakeholders, education, funding and reporting are also addressed as these are necessary for ensuring the plan's successful implementation. Action items include measures to protect of existing habitat, curb the number of vehicles on the beach, curtail aggressive beach maintenance, define critical habitat, pursue research to gain better knowledge of juvenile survivorship and dispersal, and increase public awareness through activities, publications, toad posters, toad stickers and more.

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DEMOGRAPHIC TRAITS OF INTRODUCED COMMON WALL LIZARDS (Podarcis muralis) ON VANCOUVER ISLAND

Patrick T. Gregory
Department of Biology, University of Victoria, PO Box 3020, Victoria, BC V8W 3N5, Telephone: (250) 721-7103; FAX: (250) 721-7120; E-mail: [email protected]

Non-indigenous species represent potential threats to the persistence of native species. It is therefore important to understand the ecology of introduced species in order to develop appropriate mitigation strategies when needed. Here, I describe some basic demographic attributes of common wall lizards (Podarcis muralis), a European species, introduced near Victoria, British Columbia, in the early 1970s. Male and female wall lizards reached similar body lengths, but males had relatively longer tails and were heavier than non-gravid females. Gravid females were found in all months from May-July, inclusive, but hatchlings did not appear in the field before late August. Thus, individual females apparently produce only one clutch per year. Growth rate was highest in small lizards and maturity probably was attained in the second full summer of life. As is generally true of injury patterns, large lizards were more likely than small lizards to have experienced tail loss prior to capture. These results suggest that P. muralis on southern Vancouver Island are fundamentally similar demographically to conspecifics at sites within the species' natural range in Europe. However, whether P. muralis on Vancouver Island is a threat to the native northern alligator lizard, Elgaria coerulea, remains an open question. Anecdotal observations suggest that wall lizards negatively affect alligator lizards, but both species coexist at some sites and recent studies of behavioural interactions between the two species are somewhat equivocal.

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EXPLORING THE LIMITS OF A RANGE: Thamnophis sauritus IN NOVA SCOTIA

T. Herman¹, R. Wassersug², J. McNeil¹, J. Todd ², S. Bell², G. Bourque¹, B. Caverhill¹, M. Lawton¹, E. Newton¹, N. Seguin¹ and J. Caron^1
1Biology Department, Acadia University, Wolfville NS B4P 2R6
²Department of Anatomy & Neurobiology, 5850 College Street, Dalhousie University, Halifax, NS B3H 1X5, 1902 585 1469 2902 494 2244 ph
1902 585 1059 fax
[email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected], [email protected]

In Canada, the Eastern Ribbonsnake (Thamnophis sauritus) reaches its northeastern limit in isolated pockets of southwestern Nova Scotia. We used 1) historical records and extensive visual searching to locate populations in Nova Scotia, and 2) radio-telemetry, capture-mark-recapture and direct observation to assess abundance, activity and movement, and to locate hibernacula at one intensively sampled site in Kejimkujik National Park. At this site 105 individuals were marked in 2001, and a subset of 13 adults were implanted with radio transmitters and tracked from May until November. At the same site in 2004, 135 snakes were observed and captured, and their positions, behaviour and environmental characteristics noted. In April, newly emerged snakes were most abundant in two relatively rocky areas at the edge of a floodplain. By mid-May all snakes were immediately adjacent to the nearest body of water. In September snakes concentrated in a grassy area several meters from water. One presumed mating aggregation of 10+ snakes in <5 m radius was observed at this time. By mid-October most snakes were again in rocky areas away from water. Snakes were rarely observed basking fully exposed. Based on 11 observations of feeding on anurans (Ranidae) and fish (Cyprinidae), the species appears to be a sedentary ambush predator. Radio telemetry yielded only one hibernaculum, but spring and fall concentrations suggest that snakes hibernate in rocky areas near the water table. Our extensive searches have confirmed the species' presence on three watersheds in southwestern Nova Scotia. However, success of these labour-intensive efforts has been limited by the apparently patchy distribution of the species in space and time, its cryptic nature and the high density of vegetative cover in its preferred habitats.

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Xenopus tropicalis: A NOVEL SURROGATE SPECIES FOR AMPHIBIAN TOXICOLOGY

Natacha S. Hogan and Vance L. Trudeau
Centre for Advanced Research in Environmental Genomics (CAREG), Department of Biology, University of Ottawa, Ontario, Ph: (613) 562-5800 ext.6015, Fax: (613) 562-5486, [email protected] , [email protected]

With the development of standardized toxicity testing protocols, amphibians are becoming a favoured model animal for evaluating the effects of environmental compounds. As with fish, individual amphibian species have unique characteristics that make them suitable for measuring specific endpoints. Size of larvae and adults, developmental rate, animal husbandry and ease of rearing are some factors to consider when choosing a species model. Xenopus laevis has long been exploited as a laboratory animal for studying early vertebrate development and more recently as a surrogate species for amphibian toxicity testing. However, X. tropicalis also presents unique opportunities to study how aquatic pollutants affect vertebrate development. X. tropicalis has a shorter generation time of 4-6 months and the adults are significantly smaller than X. laevis. In addition to these rearing advantages, X. tropicalis has one of the smallest genomes among amphibians (20 chromosomes, half the size of X. laevis) and is a diploid species. In fact, a genome sequencing initiative for X. tropicalis is underway and near completion (consult: http://genome.jgi-psf.org/Xentr3/Xentr3.home.html). We have established a colony of X. tropicalis and are currently optimizing conditions for tadpole rearing. In this presentation, we will describe some of our current work using X. tropicalis in comparative toxicity testing, along with future projects involving the characterisation of sexual development and assessment of endocrine disruption using thyroid-response assays.

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THE GENETICS OF PERIPHERAL POPULATIONS

Briar J. Howes and Stephen C. Lougheed
Department of Biology, Queen's University, Kingston, Ontario, K7L 3N6, Tel: (613) 533-6128, (613) 533-6000 ext. 75051, Fax: (613) 533-6617, [email protected] , [email protected]

All species, no matter how endemic or broadly distributed, have ranges that are geographically circumscribed. Evolutionary hypotheses suggest that a species' range is limited because geographically peripheral populations do not adequately adapt to their local conditions and continue range expansion. It has been suggested that peripheral populations lack the genetic variation needed to adapt to different conditions beyond the species' range, or that local adaptation in peripheral populations is precluded because of asymmetrical gene flow from more geographically central populations. We test these hypotheses using genetic data (mtDNA and microsatellites) from 52 populations across the range of the five-lined skink (Eumeces fasciatus). Specifically, we examine how post-glacial dynamics and historical range fragmentation may have shaped intraspecific diversity, whether "soft" peripheral populations (populations which are not bordered by an obvious physical boundary) and "hard" peripheral populations (populations which are bordered by an obviously inhospitable boundary) display different patterns of intrapopulation genetic diversity, and evaluate whether immigration significantly exceeds emigration in peripheral populations of this species. Our results shed light on the genetic factors involved in the maintenance of a species range and help us to understand the forces acting on our own northern peripheral populations of eastern Canada's only lizard species.

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THE EFFECT OF SEX RATIO ON SEXUAL SELECTION IN PAINTED TURTLES (Chrysemys picta) /L'EFFET DU RAPPORT DE SEXE SUR LA SÉLECTION SEXUELLE CHEZ LES TORTUES PEINTES (Chrysemys picta)

Elinor J. Hughes¹ and Ronald J. Brooks^2
1Department of Integrative Biology, University of Guelph, Guelph, ON, N1G 2W1, Phone: 519-824-4120 x58360, Email: [email protected]
²Department of Integrative Biology, University of Guelph, Guelph, ON, N1G 2W1, Phone: 519-824-4120 x53944, Email: [email protected]

Sexual selection models predict that in systems based on female mate choice, the intensity of sexual selection on male traits will increase as the sex ratio becomes more male-biased. I am investigating the influence of sex ratio on sexual selection in two populations of painted turtle (Chrysemys picta): one female-biased and one male-biased. Painted turtle mating is based on female choice; male painted turtles are much smaller than females (making coercion unlikely) and males court females by displaying with highly elongated foreclaws. Copulation is not limited by gametogenesis in painted turtles and models indicate that variation in male mating success is small when there is little limitation on mating opportunities. Hence, I hypothesize that sex ratio will not influence sexual selection in painted turtles. I will investigate three main questions. First, are sexually dimorphic traits in male painted turtles maintained in the population by female mate choice and do these traits truly signal male quality? Second, are there other factors that influence sexual selection in painted turtles? Third, is sexual selection influenced by the sex ratio of the population? By answering these questions, I will be able to create a sexual selection model for pond turtles that could be used to further our understanding of sexual trait divergence. Financed by an NSERC grant to R.J. Brooks.

Les modèles de sélection sexuelle prévoient que dans les systèmes où la femelle possède le choix d'accouplement, l'intensité de la sélection sur les traits masculins augmentera comme le rapport de sexe devient plus biaisé vers les mâles. J'étudie l'influence du rapport de sexe sur la sélection sexuelle dans deux populations de tortues peintes (Chrysemys picta) avec les rapport de sexe ci-contre. L'accouplement chez les tortues peintes est basé sur le choix de la femelle. Les tortues peintes mâles sont plus petits que les femelles, rendant la coercition peu probable, et les mâles courtisent les femelles avec leurs griffes de main élongées. La copulation n'est pas limitée par la gamétogenèse, et les modèles indiquent que le succès reproductif chez les mâles possède peu de variation lorsque les opportunités d'accouplement ne sont pas limitées. Donc, je suppose que le rapport de sexe n'influence pas la sélection sexuelle chez les tortues peintes. J'étudierai trois questions: si le dimorphism des traits chez les tortues peintes mâles est maintenu dans la population par le choix d'accouplement des femelles et si ces traits signalent vraiment la qualité masculine, s'il y a d'autres facteurs qui influencent la sélection sexuelle chez les tortues peintes et si la sélection sexuelle est influencée par le rapport de sexe pour la population. Puis, je développerai un modèle de sélection sexuelle pour les tortues qui pourra enrichir notre compréhension de la divergence des traits sexuels. Financé par une allocation de CRSNG à R.J. Brooks.

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LARGE BODY TEMPERATURE FLUCTUATIONS OF EASTERN FOXSNAKES (Elaphe gloydi) DURING VOLUNTARY COLD-WATER SWIMMING IN THEIR NATURAL HABITATS

Anna Lawson¹, Carrie A. MacKinnon², E. D. Stevens³, Ronald J. Brooks⁴
Department of Integrative Biology, University of Guelph
¹Telephone: 705 745-4458, [email protected]
²Telephone: 519 928-2837, [email protected]
³Telephone: 519 824-4120 ext. 52137 , [email protected]
⁴Telephone: 519 824-4120 ext. 53944, [email protected]

We examined thermal biology of free-ranging terrestrial foxsnakes (Elaphe gloydi), voluntarily swimming in cold water during spring, in Georgian Bay, Canada. Using temperature-sensitive radio-telemetry, we recorded body temperatures of foxsnakes during 12 cold-water swims, and subsequent warming on shore. During these swims, water temperatures ranged from 11-22�C and distances of 85-1330 m were travelled. Snakes that were in cold water long enough equilibrated with water temperature and did not maintain a body temperature above ambient. The largest observed drop in body temperature was 22.6�C (over 11 min) and the largest increase was 23�C (over 66 min). Such large, rapid temperature fluctuations have not previously been reported in detail from snakes in the field. Twice as many telemetry observations as expected occurred between 12:00 and 14:00, suggesting snakes chose to swim midday. Additionally, our results suggest that foxsnakes bask to raise their temperature prior to swimming in cold water. We compared swimming speed and the coefficient of temperature change among foxsnakes and other snake species. Swimming speed was positively correlated with water temperature.

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AMPHIBIAN CONSERVATION: BACK TO THE FUTURE

David Lesbarrères¹ and Mike Fowler^2
1Biology Department - Laurentian University, Ramsey Lake Road, Sudbury, Ontario, P3E 2C6, E-mail: [email protected] , Tel: 1-(705) 675-1151 x2275, Fax: 1-(705) 675-4859
²Integrative Ecology Unit, Department of Biological and Environmental Sciences, PO Box 65 (Biocenter 3, Viikinkaari 1), FIN-00014 University of Helsinki, Finland. E-mail: [email protected] , Tel: +358-9191-57730

The success of many pond restorations is not well documented. Following a highway construction, a restoration begun in 1999 in western France allowing the assessment of restoration efforts and changes through time. A survey was carried out on the amphibian community of eight ponds before they were destroyed. Substitutive ponds were created according to precise floristic and pedological criteria, following the old pond characteristics and taking into account the species attending them. Data are presented on species richness and ecological factors for the new ponds and compared to the initial levels. Presence of amphibian species was recorded every year during the breeding period. Species richness and abundance declined during the two years consecutive to the construction of the substitutive ponds but they increased thereafter, recovering in most of the cases to the initial levels. Fauna and flora indexes were correlated until a threshold after which over vegetation had negative effects on the establishment of amphibian populations. Likewise, an increase in the number of vegetation strata was positively correlated with species richness. Population models were used, incorporating landscape characteristics to assess current and long term population viability. The success of the restoration is specific and amphibian species present different colonisation capacities, improving our understanding of the maintenance of species richness in aquatic environments.

Le succès des projets de restauration de mares est mal documenté. A la suite de la construction d'une autoroute, un projet de restauration a débuté en 1999 dans l'ouest de la France permettant l'évaluation de ce type de projet ainsi que la dynamique des populations d'amphibiens concernées. Une étude a été menée sur les communautés d'amphibiens de huit mares avant que celles-ci ne soient détruites. Des mares de substitution ont été créées en suivant les caractéristiques écologiques des anciennes mares et des espèces observées jusqu'alors. La présence des espèces a été mesurée chaque année lors de la période de reproduction. La richesse spécifique et l'abondance ont diminué durant les deux années qui ont suivi la construction des nouvelles mares mais ces valeurs ont augmenté par la suite, retrouvant leurs valeurs initiales dans la plupart des cas. Une corrélation a été observée entre des indices de faune et de flore jusqu'à un seuil au-delà duquel un surplus de végétation a un effet négatif sur l'établissement des populations d'amphibiens. De la même manière, l'augmentation du nombre de strates végétales est positivement associée avec la richesse spécifique. Des modèles populationnels incorporant les caractéristiques écologiques des mares ont ensuite été utilisés pour estimer la viabilité présente et à long terme des populations. Nous avons montré que le succès du projet de restauration est spécifique et que les espèces présentent différentes capacités de colonisation, améliorant notre compréhension du maintien de la richesse spécifique en milieu aquatique.

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SURVIVORSHIP AND DIFFERENTIAL LONGEVITY IN THE SPOTTED TURTLE (Clemmys guttata)

Jacqueline D. Litzgus
Affiliation: Department of Biology, Laurentian University, Sudbury, ON P3E 2C6, Phone: 705-675-1151 ext 2314, Fax: 705-675-4859, Email: [email protected]

Turtles are in decline world-wide, and few studies have collected the long-term, age-specific demographic data needed to construct life tables and thus identify the life history stages critical to population viability and conservation. Here I report estimates of survivorship and longevity of the spotted turtle (Clemmys guttata) using modified logarithmic decay equations and 24 years of mark-recapture data collected from a population at the northern extreme of the species' range in Ontario. Spotted turtle survivorship and longevity estimates are among the highest values reported for any animal species, and females are substantially more long-lived than males. Minimum annual adult female survivorship is 96.5%, maximum longevity is 110 years, and age at maturity is 12 years. Minimum male survivorship is 94.2%, maximum longevity is 65 years, and age at maturity is 11 years. The greater longevity of females may have evolved as a compensatory mechanism to offset delayed sexual maturity and low annual clutch frequency in the north. The selective pressure on males for extended longevity may not be as great because their fitness can be ensured in a shorter time frame through the species' promiscuous mating system. Alternatively, males may live shorter lives as a result of a greater cost of reproduction (e.g., sperm production, courtship, copulation). This ongoing study is the longest-running on the spotted turtle, yet insufficient age-specific data have been gathered to construct a life table, particularly because egg and hatchling survival rates remain unknown; future work should specifically focus on gathering such data. The results of the current study have important management implications when considering which life history stages to protect for maintenance of population viability of long-lived vertebrates.

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PERIPHERAL POPULATIONS AND THEIR POTENTIAL CONSERVATION VALUE (Plenary address)

Stephen C. Lougheed
Biology, Queen's University, Kingston, Ontario, Canada K7L 3N6., Tel: (613) 533-6128, Fax: (613) 533-6617 , [email protected]

Canada is depauperate in herpetofaunal diversity compared to most other countries. Moreover, for many of the approximately 86 Canadian amphibian and reptile species, the bulk of their ranges occur in the continental USA. Thus, many herpetofaunal species in Canada (and almost all that are of conservation concern) are represented by northern, geographically peripheral populations only. Peripheral populations may have conservation value because they tend to be diverged genetically and phenotypically from core populations, and because they may represent future sites of speciation (i.e. Mayr's peripatric model of speciation). As such it has been argued that peripheral populations should receive conservation priority both because they are repositories of unique aspects of intraspecific diversity that may be important in changing environmental circumstances and because they may generate future diversity. Comprehensive empirical support for these suggestions is lacking especially for amphibians and reptiles. An additional complication is that we still do not know why range boundaries exist, and thus what precludes peripheral populations from adapting to local environmental circumstances and continuing range expansion. In my talk I will briefly quantify and summarize the degree of peripherality of Canadian herpetofauna, explore the notion that peripheral populations have disproportionate conservation value, and present a suite of hypotheses that have been proposed (but seldom adequately tested) to explain range limits. I will argue that Canadian conservation strategies for species at risk would derive great benefit from a coordinated research effort to address these key knowledge deficits.

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WHY DID THE REPTILE CROSS THE ROAD? LANDSCAPE FACTORS ASSOCIATED WITH ROAD MORTALITY OF SNAKES AND TURTLES IN THE SOUTH EASTERN GEORGIAN BAY AREA

C. A. MacKinnon¹, L. A. Moore³, and R. J. Brooks²
Department of Integrative Biology, University of Guelph, Guelph, Ontario, N1G 2W1
¹[email protected] , Tel: (519) 928-2837
²[email protected] , Tel: (519) 824-4120, Fax: (519) 767-1656
³Georgian Bay Islands National Park, Parks Canada, P.O. Box 786, Fort Simpson, NT, X0E 0N0, [email protected] , Tel: (867) 695-3028

Road mortality is believed to contribute to population declines in snakes and turtles, but there have been few attempts to quantify landscape features associated with road mortality in these taxa. A secondary road near Georgian Bay, Ontario (45 52'N, 80 50'W) was surveyed daily by automobile between April and October, 2003 and 2004. We measured landscape factors associated with roadkill of reptiles using multivariate statistics and a geographic information system (GIS). A total of 340 road crossings were analyzed (269 snakes, 71 turtles; 91% dead on the road), 44 of which involved species at risk in Canada. Snake crossings peaked during August, whereas turtle crossings peaked during June. Multiple regressions were performed to assess the relative importance of the measured landscape factors using 1) total reptile, 2) snake and 3) turtle crossing counts for buffered, equal-length road segments as output variables. The following landscape variables explained much (R2 = 0.354) of the distribution of reptiles killed along this road: distance from Georgian Bay, driveways, buildings, road intersections, adjacent wetlands, and water crossings. Roadkill tended to be closer to Georgian Bay and further from driveways. Factors contributing to roadkill for species at risk should be considered prior to planning roadway expansion.

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PHYLOGEOGRAPHY OF STREAM SALAMANDERS IN QUEBEC AND LABRADOR

Tricia M. Markle and David M. Green
Redpath Museum, McGill University, 859 Sherbrooke West, Montreal, Quebec, H3A 2K6, Canada, Phone: (514) 398-4086 ext. 3190 or 4088, Fax: (514) 398-3185, Email: [email protected] , [email protected]

The Northern Two-lined, Eurycea bislineata, and the Northern Dusky, Desmognathus fuscus, are both small stream dwelling salamanders commonly found throughout eastern North America. In Canada, E. bislineata has an extensive northern range whereas D. fuscus is restricted to southern Quebec and a single site in the Niagara Gorge of Ontario. What determines the northern range limits of these salamanders is unknown. However, if the St. Lawrence River acts as a barrier to gene flow, then isolated populations of E. bislineata on the north shore may have had the opportunity to adapt to local conditions and expand their range accordingly. Desmognathus fuscus may not have had the same opportunity, and may be restricted to the south if populations on the northern periphery of the range are swamped by genes adapted to more southern conditions. Accordingly, phylogeographic patterns throughout the Canadian ranges of these salamanders were investigated in 58 populations of E. bislineata, including new populations in northern Quebec and Labrador, and 11 populations of D. fuscus. The range of E. bislineata was found to be far more extensive in northern Canada than previously recorded. Sequence variation in the mitochondrial cytochrome b gene of E. bislineata populations revealed a genetically distinct group of four adjacent populations on the north shore of the St. Lawrence River. Indications are that an isolated population near Trois-Rivieres underwent a genetic change and spread northward. Although molecular analysis did not reveal any differences between Labrador and Quebec groups, morphometric analysis of individuals from all the populations revealed a distinct Labrador morphotype. For D. fuscus populations, no genetic or morphometric differences were found.

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A VALUABLE TOOL TO ASSESS THE STRENGTH OF BIOLOGICAL HYPOTHESES IN HERPETOLOGY: AKAIKE'S INFORMATION CRITERION (AIC)

Marc J. Mazerolle
USGS Patuxent Wildlife Research Center, Laurel, MD 20708-4017 USA, Phone: (301) 497-5636, Fax: (301) 497-5545, Email: [email protected]

Herpetologists frequently use observational studies to explain a given pattern, such as the number of individuals in a habitat patch, with a large number of explanatory (i.e., independent) variables. To elucidate such relationships, we have long relied on hypothesis testing to include or exclude variables in regression models, although the conclusions often depend on the approach used (e.g., forward, backward, stepwise selection). Akaike's Information Criterion (AIC) is remarkably superior in model selection (i.e., variable selection) than hypothesis-based approaches. It it is simple to compute and easy to understand, but more importantly, for a given data set, it provides a measure of the strength of evidence for each model that represents a plausible biological hypothesis relative to the entire set of models considered. Using this approach, one can then compute a weighted average of the estimate and precision for any given variable of interest across all the models considered. This procedure, termed model-averaging or multimodel inference, yields precise and robust estimates. In this paper, I illustrate how these techniques can be used in the conservation of amphibians and reptiles. The AIC and measures derived from it is should be routinely adopted by herpetologists, particularly those conducting field studies.

Les herpétologistes utilisent fréquemment des études d'observation sur le terrain dans le but d'expliquer des patrons, tels que le nombre d'individus dans une parcelle d'habitat, à l'aide de plusieurs variables explicatives (indépendantes). Afin d'élucider ce genre de relations, nous avons utilisé pendant longtemps les tests d'hypothèses afin d'inclure ou d'exclure des variables dans des modèles de régression, bien que les conclusions dépendent souvent de l'approche utilisée (e.g., sélection ascendante, descendante, pas à pas). Le critère d'information d'Akaike (AIC) est remarquablement supérieur aux tests d'hypothèses pour la sélection de modèles (i.e., sélection de variables). En plus d'être facile à calculer et à comprendre, l'AIC procure une mesure du degré d'évidence de chaque modèle qui représente une hypothèse biologique parmi l'ensemble des modèles considérés. En utilisant cette approche, on peut également calculer une moyenne pondérée de l'estimé et de la précision d'une variable d'intérêt pour l'ensemble des modèles considérés. Cette procédure, nommée pondération de modèle ou inférence multi-modèle, donne des estimés précis et robustes. J'illustre comment ces techniques peuvent être utilisées dans les travaux de conservation des amphibiens et des reptiles. Les herpétologistes, particulièrement ceux menant des études de terrain, devraient adopter l'AIC et les mesures qui en découlent.

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IMPACTS OF ROW CROP AGRICULTURE ON SEXUAL DEVELOPMENT OF ANURANS

Tana V. McDaniel¹, Pamela A. Martin¹, Chris Marvin², Mark McMaster², Jim Sherry^2
1Canadian Wildlife Service, Environment Canada, PO Box 5050, 867 Lakeshore Rd E, Burlington, ON, L7R 4A6, email: [email protected], [email protected]
²National Water Research Institute, Environment Canada, PO Box 5050, 867 Lakeshore Rd E, Burlington, ON, L7R 4A6

Intensive row crop agriculture featuring corn and soybean production, is predominant in southwestern Ontario where the two crops account for over 50% of the total acreage of crops grown. This form of agriculture relies heavily on pesticide and nutrient inputs for continued success under conventional systems. The corn herbicides atrazine and metolachlor, are the two most heavily applied pesticides in Ontario and are routinely detected in tributaries draining agricultural watersheds. Field and laboratory studies have indicated exposure to atrazine may disrupt normal sexual development in male anurans, causing reductions in testosterone levels, laryngeal muscle diameter, and abnormal testes development. Pesticide levels and water quality data was collected from 33 farm ponds and agricultural drains in southwestern Ontario, two agricultural reference sites as well as four non-agricultural reference sites in August and September, 2003 and monthly from April through August in 2004. Atrazine and metolachlor were detectable in most samples, exceeding 1 �g/L at some sites. Blood samples were obtained from leopard and green frogs for analysis of sex hormones, and vitellogenin. Gonads were excised for histomorphological assessment. Analysis of frogs from late summer 2003, revealed that circulating testosterone levels were negatively correlated with atrazine concentrations in pond water in juvenile male leopard frogs (r = 0.74; p = 0.014) and adult female leopard frogs (r = 0.59; p < 0.008). No relationship was found between sex steroid levels in frog plasma and concentrations of atrazine and metolachlor in the water in 2004, contrary to results from 2003. This may be due to lower concentrations of atrazine and metolachlor in 2004. Agricultural sites, particularly those in Chatham exhibited a high percentage of males with ova-testes (45%), as compared to control sites (10%).

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INFLUENCE OF WATER CONDITIONS ON THE EMBRYONIC SURVIVORSHIP OF THE OREGON SPOTTED FROG (Rana pretiosa)

René McKibbin¹, Christine Bishop², and Russ Haycock³
Canadian Wildlife Service, 5421 Robertson Rd, Delta, BC V4K 3N2.
¹Tel 604-940 4728. Fax 604-946 7022. [email protected]
²Tel 604-940 4671. Fax 604-946 7022. [email protected]
³Hyla Environmental Services Ltd., 636 Thurston Close, Port Moody. BC, V3H 4J3, Tel 604-469 2910. Fax 604-469-5753. [email protected]

The Oregon spotted frog (Rana pretiosa) was listed as endangered in an emergency listing in 1999 by the Committee on the Status of Endangered Wildlife in Canada [COSEWIC]. There are only three known locations of the subpopulation in Canada. These known subpopulations are located in isolated sites in the extreme southwest corner of British Columbia. One of the populations has shown a steady decline since 1997. At present, the cause of poor fecundity and embryonic survivorship at one of the sub sites at the Aldergrove site is not known but indicates the need to obtain an understanding of embryonic survivorship in the context of population viability research. This research examined the question of whether water conditions influence the embryonic survivorship at two subpopulations located at Seabird Island and Aldergrove, BC. A sub-sample of 15-30 eggs per clutch was transferred into Nytex holding cages and development monitored in-situ using Gosner staging tables. Free swimming hatchlings were released at the site where the eggs were oviposited. Water conditions at each site were assessed by collecting water samples for trace metal analysis, fecal and total coliform and water chemistry. Water temperature was also recorded. At Aldergrove embryonic survivorship varied between 0.09 and 0.45 at sub site A and 0.71 and 0.96 at sub site B. At Seabird Island embryonic survivorship was between 0.67 and 0.86. Initial analyses indicate that no extreme water quality conditions occur at any of the two study sites and most likely do not contribute to poor embryonic survivorship at Aldergrove.

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UPDATE FROM THE KAWARTHA TURTLE TRAUMA CENTRE 

Kristy McNab
Kawartha Turtle Trauma Centre, c/o Riverview Park & Zoo, PO Box 4125 Peterborough ON. K9J 6Z5, Phone: (705) 748-9301 ext. 2303, email: [email protected]

The Kawartha Turtle Trauma Centre in Peterborough, Ontario, has been treating road injured turtles for four seasons and is receiving turtles from across the province, often from other wildlife rehabilitators. Painted, Snapping and Blanding's turtles are the three species most often admitted to the centre. Snapping turtles have a high incidence of skull and jaw fractures and carapace shearing, and Painted turtles are usually admitted for shell fractures. Blanding's turtles are often treated for carapace, bridge and jaw fractures. Of great concern is the prevalence of eye injury in Blanding's turtles; severe visual impairment has prevented the release of several Blanding's turtles. The method of fracture fixation most commonly used is orthopedic wire. Oesophagostomy feeding tubes are often placed and may be used for months before patients begin to eat on their own. Antibiotic therapy is being refined and the use of pain medication is increasing, the standard being that every patient recieves at least short term analgesia. Field triage and first aid may increase treatment success and release. Most important in first aid is to keep the injured animal hydrated either through soaking or the use of subcutaneous fluids. Heat stress can be treated by placing wet towels or gauze on the turtle. Mobile shell fractures can be stabilized with tape. For Blanding's turtles we encourage the use of tear gel or wet gauze lightly draped over the head to prevent further eye injury through dessication. The Centre has received its third cohort of Wood turtles to headstart. Wood turtles are being raised at the Centre for release into an endangerd population. Weights of 250g or more were reached after 20 months at the Centre. Individuals attaining sufficient size will be equipped with transmitters and released. We hope that the expertise developed in captive rearing will be potentially used for other captive rearing initiatives.

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GENETIC STRUCTURE OF THE EASTERN RED-BACKED SALAMANDER (Plethodon cinereus) IN AN URBAN LANDSCAPE

Sarah Noël¹, Martin Ouellet², Patrick Galois² and François-Joseph Lapointe^1
1Dép. sciences biologiques, Université de Montréal, C.P. 6128 Succ. Centre-Ville, Montréal, Qc, H3C 3J7, [email protected] , [email protected]
²Amphibia-Nature, 4254 rue Garnier, Montréal, Qc, H2J 3R5, Tel: 514-343-6111 ext.1031, Fax:514-343-2293, [email protected] , [email protected]

The Mont Royal, located in the heart of Montréal, represents an important reservoir of biodiversity in the urban landscape. However, it has been gradually fragmented by anthropogenic activities since the arrival of the first European settlers more than 350 years ago. Nowadays the Mont Royal presents a mosaic of forested patches isolated by roads, graveyards and buildings, into which four Eastern Red-backed Salamander (Plethodon cinereus) populations are still found. To evaluate the effect of this habitat fragmentation, genetic diversity and population differentiation were assessed with microsatellite loci and compared to the genetic structure of four populations situated in a continuous habitat, the Mont Mégantic. Results indicate that allelic richness and heterozygosity are lower in the fragmented populations. Exact differentiation tests and pairwise FST showed that the four populations from Mont Royal could be differentiated, whether populations from Mont Mégantic were non-differentiated. These results indicate that urbanization of the Mont Royal has significantly changed the genetic structure of the Eastern Red-backed Salamander and raise conservation concerns for these isolated populations.

Le Mont Royal, situé au coeur de Montréal, constitue un site important pour la biodiversité dans le paysage urbain. Toutefois, cette montagne a été graduellement fragmentée par les activités anthropiques depuis l'arrivée des premiers colons il y a plus de 350 ans. Aujourd'hui, le Mont Royal présente une mosaïque d'îlots forestiers isolés par des édifices, des cimetières, et des routes, parmi lesquels on retrouve quatre populations de salamandre cendrée (Plethodon cinereus). Afin d'évaluer les effets de cette fragmentation d'habitat, la diversité génétique et la différentiation des populations ont été évaluées à l'aide de marqueurs microsatelllites et comparées à la structure génétique de quatre populations situées dans un habitat non-fragmenté, le Mont Mégantic. Les résultats indiquent que la richesse allélique et l'hétérozygotie sont plus faibles pour les populations fragmentées. Les tests exacts de différentiation et les valeurs de Fst montrent que les quatre populations du Mont Royal sont différentes les unes des autres alors que les populations du Mont Mégantic sont similaires entre elles. Ces résultats indiquent clairement que la fragmentation du Mont Royal a modifié la structure génétique des populations de salamandres cendrées et sont inquiétants pour la survie de ces populations isolées.

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THE DRASTIC DECLINE OF THE WESTERN CHORUS FROG (Pseudacris triseriata) IN SOUTHWESTERN QUÉBEC

Isabelle Picard and Jean-François Desroches
1050-1 Saint-Marc, Sherbrooke (Québec), J1K 2T7 Canada, [email protected]

The Western Chorus Frog (Pseudacris triseriata) has undergone a drastic decline in southwestern Québec over the past 50 years; the species is now absent from about 90 % of its historical range. In April 2004, an exhaustive survey of Chorus Frog populations was made throughout its present range, with auditory monitoring at breeding ponds, in order to locate these ponds precisely and evaluate more precisely the status of this frog. A total of 803 breeding ponds dispersed in 9 metapopulations and 7 isolated populations were located. Most of these are highly at risk of destruction by residential developments. The Western Chorus Frog was not found at 4 sites where it occurred recently. Declines are observed in 5 of the 9 present metapopulations. A second survey of the breeding ponds later in the summer showed that at least 5 % of them were destroyed, and it up to 25 % in some areas. Despite the fact that the species was officially designated 'vulnerable' in Québec in 2000, the destruction of its habitats continues and at this rate the Western Chorus Frog may be extirpated from southwestern Québec in 10 to 25 years.

La Rainette faux-grillon de l'Ouest (Pseudacris triseriata) a subi un important déclin dans le sud-ouest du Québec depuis 50 ans; l'espèce est maintenant absente dans environ 90 % de son aire historique. En avril 2004, un inventaire exhaustif des populations de Rainettes faux-grillon a été réalisé dans son aire actuelle, à l'aide de l'écoute des chants, dans le but de localiser précisément les étangs de reproduction et d'évaluer de façon plus précise le statut de cette rainette. Au total, 803 étangs de reproduction répartis dans 9 métapopulations et 7 populations isolées ont été recensés, dont la plupart sont menacées par le développement résidentiel. La Rainette faux-grillon de l'Ouest est disparue de 4 sites où elle était présente récemment. Des déclins ont été observés dans 5 des 9 métapopulations actuelles. Un deuxième inventaire des étangs de reproduction réalisé plus tard dans l'été 2004 a démontré que pas moins de 5 % de ceux-ci avaient été détruits, et ce chiffre atteint 25 % dans certains secteurs. Malgré le fait que l'espèce ait été officiellement désignée 'vulnérable' au Québec en 2000, la destruction de ses habitats continue et à ce rythme la Rainette faux-grillon de l'Ouest pourrait disparaître du sud-ouest du Québec dans 10 à 25 ans.

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HOW FAR FROM THE NESTING SITE SHOULD WE PROTECT THE FOUR-TOED SALAMANDER (Hemidactylium scutatum)? A CASE OF URBAN CONSERVATION

Daniel Pouliot¹ and Héloïse Bastien^2
14230 #1 Louis-Lacroix, Trois-Rivières, Québec. G8Y 5V2 819-697-2405 [email protected]
²Héloïse Bastien : Direction de l'aménagement de la faune de la Capitale-Nationale, Ministère des Ressources naturelles et de la Faune 365, 55e Rue Ouest, Charlesbourg (Québec) G1H 7M7 Téléphone : (418) 644-8844 poste 305, [email protected]

Shortly after the discovery in 1999, of a four-toed salamander (Hemidactylium scutatum) population in the periphery of Quebec City, the modification and destruction of the forest surrounding the nesting site began. To minimize the damages to this rare species population by the residential development, we investigated the distance from the nesting site, in the terrestrial habitat, use by the four-toed salamander outside the nesting time. Our results proposed that the four-toed salamander doesn't go farther than 50 meters from the nesting site. The "Centre de données sur le patrimoine naturel du Québec" proposed a buffer zone of 150 meters. We feature that the 150 meters buffer zone should be view as two areas. Any activities or development, neither hiking trail, should be planned in the first 50m from the nesting site. Only hiking trail could be managed in the 50 to 150 meters from the nesting site. Moreover, special attention should be done to possible hydrologic modifications consequent of habitat modification outside the 150 meters buffer zone.

Peu après la découverte en 1999, d'une population de salamandres à quatre orteils (Hemidactylium scutatum) dans la banlieue de la ville de Québec, la modification et la destruction de l'habitat forestier entourant le site de ponte débuta. De manière à minimiser l'impact du développement résidentiel, nous avons cherché à quantifier la distance du site de ponte, dans l'habitat terrestre, utilisée par la salamandre à quatre orteils, en-dehors de la période de ponte. Nos résultats suggèrent que la salamandre à quatre orteils ne s'éloignent pas à plus de 50 mètres du site de ponte. Le Centre de données sur le patrimoine naturel du Québec propose une zone tampon de 150 mètres. Nous soulignons que cette zone devrait-être considérée comme deux aires distinctes. Aucune activités ou dévelopment, pas même des sentiers de randonnée pédestre, ne devrait être prévues dans les premiers 50 mètres du site de ponte. Uniquement des sentiers pédestres devrait-être tolérés dans la zone de 50 à 150 mètres du site de ponte. De plus, une attention toute particulière doit-être portée à d'éventuelles modifications des conditions hydrologiques du milieu, engendrés par des travaux réalisés au delà de la zone tampon de 150 mètres.

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EFFECT OF TEMPERATURE ON PHYSIOLOGY AND BEHAVIOUR IN TWO COLOUR MORPHS OF THE RED-BACKED SALAMANDER (Plethodon cinereus)

Daniel J. Reeves^1,2, Jacqueline D. Litzgus², and David Hackett^1
1Department of Biology, Nipissing University, North Bay, ON P1B 8L7
²Department of Biology, Laurentian University, Sudbury, ON P3E 2C6
Phone: 705-675-1151 ext 2314, Fax: 705-675-4859, Email: [email protected]

Colour polymorphisms are common in amphibians and are often viewed as adaptations to specific ecological conditions. The terrestrial eastern red-backed salamander (Plethodon cinereus) is widely distributed in forests of eastern North America, and displays colour polymorphism. Populations usually exhibit two colour morphs - a red-backed morph and a lead-backed morph, and the proportion of each morph in a population is correlated with climate. The purpose of the current study was to investigate the effect of temperature on physiological (metabolic rate) and behavioural differences between the two morphs. We hypothesised that: 1) temperature affects metabolic rate differently between the two morphs; 2) the two morphs differ in agonistic behaviour when paired against con-specifics; and 3) temperature affects the degree of agonistic behaviour. With respect to the first hypothesis, we found a trend for a difference in metabolic rate between the morphs; however, the difference was not statistically significantly at our sample size. The second and third hypotheses were supported. In agonistic trials at the warmer temperature (20�C), resident red-backed morphs exhibited more aggressive behaviours and fewer submissive behaviours than lead-backed intruders. In contrast, resident lead-back morphs were not more aggressive than red-backed intruders. At the cooler temperature (9�C), the proportion of aggressive and submissive behaviours did not differ between the morphs regardless of who was the resident. In general, salamanders exhibited more aggressive behaviours at higher temperatures than at lower temperatures. We discuss our findings in light of the species' distribution and frequencies of each colour morph in wild populations.

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ANNUAL TEMPERATURE VARIATIONS AFFECT CLUTCH FREQUENCY AND EGG SIZE IN A NORTHERN POPULATION OF PAINTED TURTLES (Chrysemys picta)

Njal Rollinson and Ron Brooks
Department of Integrative Biology, University of Guelph, ON, N1G 2W1, 519-824-4120 ext. 58360, [email protected] , [email protected]

Annual variations in clutch frequency (CF) and mean egg size (ES) have been clearly documented in several populations of Chrysemys picta. Although it has been suggested that these annual differences are temperature-mediated, previous efforts to relate variations in CF and ES to temperature have been largely unsuccessful. We investigated the relationship between annual temperature variation and CF and ES over 12 years in Algonquin Provincial Park. We predicted that warmer temperatures during the summer and fall prior to nesting and during the following spring would be associated with an increase in CF and a decrease in egg mass (EM) and egg length (EL). EM and EL were not related to fall or spring temperatures; however, an a-posteriori analysis revealed that both these parameters were negatively related to temperatures just prior to nesting season onset (r2 = 0.60-0.75, 9-13 years analyzed). We further investigated the effect of individual thermal regimes on ES by attaching Thermochron iButtons to the shells of ~50 females over two field seasons. Preliminary analyses appear to support the idea that temperature and ES are inversely related. We argue that, if temperature acts as a constraint on ES, then these findings support optimal egg size theory. Preliminary analyses further indicate that a strong relationship exists between the temperature of the previous summer and CF.

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WOOD TURTLE (Clemmys insculpta) HABITAT REQUIREMENTS AND MOVEMENTS IN NEW BRUNSWICK

Vanessa Roy and Graham Forbes
University of New Brunswick, Faculty of Forestry and Environmental Management, P.O. Box 44555, 28 Dineen Drive, University of New Brunswick, Fredericton, NB E3B 6C2, Tel: 506-452-6315, Email: [email protected] , [email protected]

In Canada, the Wood Turtle is listed as a species of concern by COSEWIC. Efforts are being undertaken to protect the remaining populations within the country. A two-year habitat selection study of Wood Turtles was undertaken by UNB from May to August 2003-2004, within the military training area of CFB Gagetown in New Brunswick. A limited number of studies have quantitatively measured habitat selection in Wood Turtles in the northern extent of their range. These studies suggest that proximity to water, low canopy cover and non-forested locations such as alder stands are selected habitat features. We hypothesize that male habitat selection is due largely to their search for females and competition with males. Two person visual searches of selected waterways along with radio-telemetry of 30 turtles were conducted over two seasons. Habitat characteristics were measured at each capture site and a corresponding random site. Conditional Logistic Regression was used to determine habitat selection models. A total of 115 individual turtles were captured over two seasons. Although non-forested locations were favoured overall, forested locations did see a significant increase in use later in the season. Distance to water varied throughout the season. The majority of observations of Wood Turtles were noted within 300 m, several individuals were also noted at further distances than recorded in previous studies. Habitat use was highly variable between individuals and throughout the active season. An initial observation of the data does not suggest a difference between the sexes.

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FACTORS AFFECTING AMPHIBIAN DISTRIBUTION AND COMMUNITY STRUCTURE IN NOVA SCOTIA

Ronald W. Russell
Department of Biology, Saint Mary's University, 923 Robie St., Halifax, Nova Scotia, B3H 3C3, Phone: (902) 420-5645, Fax: (902) 496-8285, Email: [email protected]

Nova Scotia wetlands were surveyed for amphibians from 2002 to 2005. Wetlands on game reserves, parks, coastal barrens, and developed areas were included. Species richness in these wetlands was stable over the four study years, however there was substantial species turnover between years. Water chemistry was generally not useful in predicting amphibian species richness. Acidic wetlands with pH less than 4 were not used by amphibians. Wetland hydroperiod and presence of fish predators were major factors affecting species richness. Additionally, distance from human disturbance was a significant factor in determining amphibian species richness in ponds. Community structure was assessed using stable isotope ratios of N and C. Preliminary data indicate potential competitive relationships between wood frog and spring peeper tadpoles and identified predatory invertebrates in amphibian communities.

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EXCAVATION OF FRESHWATER TURTLE EGGS IS A NON-DELETERIOUS METHOD FOR OBTAINING FECUNDITY AND EGG MORPHOMETRIC DATA

Jason Samson¹, Elinor J. Hughes, and Ronald J. Brooks^2
1Department of Natural Resource Sciences. Macdonald Campus of McGill University., 21,111 Lakeshore Road, Sainte-Anne de Bellevue, Québec, Canada. H9X-3V9, email:[email protected]
²Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada., N1E 2W7 519-824-4120 x58360, Email: [email protected] , [email protected]

It has been suggested, and verified in artificial conditions, that handling eggs of various turtle species can be deleterious to embryos. However, excavating turtle nests remains an ideal method for obtaining accurate fecundity and egg morphometric data. We tested the hypothesis that handling turtle eggs decreases embryo survival in a population of midland painted turtle (Chrysemys picta marginata) that has been extensively studied since 1978 and where more than 2300 nests have been excavated since 1983. We compared embryo survival in handled and non-handled natural nests during the summers of 2002, 2003 and 2004. All nests were protected from mammalian predators. Upon excavation of the nests in the following springs, we did not find differences in survival between the two treatments, suggesting that the benefits in knowledge gained from nest excavation far outweigh the possibility of a small increase in mortality that could arise from handling the eggs. Moreover, we propose that excavating nests is beneficial for the management of endangered turtle species because the eggs can subsequently be relocated, protected, or incubated for headstarting programs when needed.

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EMERGENT INFECTIOUS DISEASES IN THE LEOPARD FROG (Rana pipiens) IN CENTRAL ONTARIO

Valerie St-Amour¹ and Michael Berrill^2
1Department of Biology, Laurentian University, Sudbury, Ontario, Canada P3E 2C6, Email: [email protected] , Tel: 1-(705) 675-1151, Fax: 1-(705) 675-4859
²Department of Biology, Trent University, 1600 West Bank Drive, Peterborough, Ontario, Canada K9J 7B8, Email: [email protected] , Tel: 1-(705) 748-1011

Emergent infectious diseases (EID's) are one of the most pressing issues of amphibian conservation. They have been linked to several amphibian declines and are continually being discovered in new areas and species. Two of the most serious diseases, Ranavirus and chytrid fungus have recently been found in Ontario. Ranavirus was found both in woodfrog (Rana sylvatica) and leopard frog (R. pipiens) populations while chytrid was present in the bullfrog (R. catesbeiana). Leopard frogs are currently sold and distributed across Ontario as bait and may be contributing to the spread of EID's. Using genetic analysis and histological methods, wild, captive and bait shop samples of R.. pipiens were analyzed to test the hypothesis that Ranavirus and chytrid were present in these Ontario populations. Local bait shops were sampled to determine if infected frogs are being transported around Ontario through the recreational sale of bait frogs. Wild samples were also used to gain a better idea of the range of the virus in central Ontario. Captive populations were kept to determine if the virus spread in captive situations due to the immune suppression caused by stress. Chytrid was searched for in the wild samples to determine if it is playing a part in amphibian declines in this region. Ranavirus was discovered in one of the six wild populations, in the bait shops and in all of the captive populations. Chytrid was also present in several of the samples. For this reason the commercial harvesting of bait frogs should be stopped immediately.

Les maladies infectieuses émergentes sont un des plus importants problèmes dans la conservation des amphibiens. Elles sont responsables du déclin de nombreuses populations et sont continuellement observées chez de nouvelles espèces. Deux de ces maladies, Ranavirus et le champignon chytride ont récemment été découvertes en Ontario. Ranavirus a été observé chez la grenouille des bois (Rana sylvatica) et la grenouille léopard du nord (R. pipiens) alors que le chytride fut observé chez le ouaouaron (R. catesbeiana). La grenouille léopard est vendue et distribuée à travers l'Ontario en tant qu'appât et potentiellement contribue à la diffusion de ces maladies. Grâce à des analyses génétiques et histologiques, des grenouilles léopard ont été testées pour ces deux maladies. Des magasins de pêche ont été échantillonnés pour déterminer si des grenouilles infectées traversent l'Ontario au travers de l'activité de pêche à l'appât. L'étude de populations sauvages a permis de déterminer l'expansion du virus dans le centre de la province. Enfin, des individus tenus en captivité ont également été analysés pour identifier une possible diffusion du virus due à l'altération des défenses immunitaires en situation de stress. Le chytride a été recherche dans les populations sauvages pour évaluer son rôle dans le déclin des amphibiens dans la région. Ranavirus a été découvert dans une des six populations sauvages analysées, dans les magasins de pêche et dans toutes les populations captives. Le chytride était présent dans de nombreux échantillons. Pour cette raison, la distribution commerciale de grenouille en tant qu'appât devrait cesser immédiatement.

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BEAVER (Castor canadensis) AS A SURROGATE SPECIES FOR CONSERVING ANURAN AMPHIBIANS ON BOREAL STREAMS

Cameron E. Stevens¹, Cynthia A. Paszkowski², and A. Lee Foote³
Dept. of Biological Sciences, University of Alberta, Edmonton, AB T6G 2E9, ¹ [email protected] ; P(780) 492-5751; F(780)492-9234, ² [email protected],
³Dept. of Renewable Resources, University of Alberta, Edmonton, AB T6G 2H1; [email protected]  

We explored the use of beaver (Castor canadensis) as a surrogate species for amphibian conservation on small (1st-4th order) streams in the Boreal Foothills of west-central Alberta. First, we examined if the presence of beaver affected the abundance of anurans amphibians using call surveys and pitfall trapping on unobstructed streams and beaver ponds. We also characterized the distribution of beaver ponds and the potential effects of landscape features, road construction and forest harvesting on beaver pond occupancy of streams using a novel combination of a digital elevation model and vegetation inventory data in GIS. Call surveys clearly suggested that beaver create breeding habitat for the boreal chorus frog (Pseudacris maculata), wood frog (Rana sylvatica) and western toad (Bufo boreas). No calling males of any species were recorded on unobstructed streams. Pitfall trapping showed that the wood frog exhibit high rates of juvenile recruitment on beaver ponds given that more individuals were captured on beaver ponds versus unobstructed streams and that young-of year represented the majority of wood frog captures (84%). A strong correlation between percent landscape occupied with beaver ponds and abundance of young-of-year wood frogs on unobstructed stream suggests that anurans captured along streams originated from beaver ponds. Using a generalized linear mixed-effect model, we found that the probability of beaver pond occurrence on streams was positively associated with elevation and stream order but unrelated to riparian forest height and distance to nearest road. In addition, proximity of streams to cutblocks reduced the probability of beaver pond occupancy even if Populus spp. was regenerating in the logged area. The high number and area of beaver ponds relative to basin (i.e., non-beaver) ponds in the Boreal Foothills suggests that beaver can play a key role in maintaining regional populations of amphibians. Beaver food requirements and dam-building patterns should be incorporated in management strategies as part of a surrogate species approach to amphibian conservation.

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STATUS OF THE WESTERN TOAD AND ITS USE OF 'BORROW PITS' IN THE FOOTHILLS OF WEST-CENTRAL ALBERTA

Cameron E. Stevens¹, Cynthia A. Paszkowski², David Stringer⁴ and Shelly Boss³
Dept. of Biological Sciences, University of Alberta, Edmonton, AB T6E 2E9, ¹ [email protected]; P(780)492-5751; F(780)492-9234, ² [email protected], ³ [email protected]
⁴#30 3705 Fonda Way SE, Calgary, AB T2A 6G9; [email protected]

Populations of western toad (Bufo boreas) have declined or disappeared from much of the species southern range in the U.S. To assess distributions and densities of the western toad in the foothills of west-central Alberta, Canada we conducted visual surveys of 130 natural waterbodies in watersheds of the Pembina and North Saskatchewan Rivers in early and late summer 2000. Encounter rates were consistently low throughout the study area (0.2-0.3 toads/hr), one-tenth the rate for the co-occurring wood frog (Rana sylvatica), and nearly one-third the value reported in the literature for a toad population in south-western British Columbia during the late 1970s. Large-scale pitfall trapping of breeding and non-breeding sites during 2001 and 2002 showed differing age structures between wood frog and western toad populations, and that recruitment of age-0 juveniles in western toad populations was low. On potential breeding ponds, more age-1+ toads were captured than age-0 toads, and the difference in numbers between age classes was greater on 'borrow pits' (human-created roadside ponds) compared to beaver ponds indicating that borrow pits might be ecological sinks providing poor larval habitat. Borrow pits had either dried prior to juvenile emergence or had oligotrophic to mesotrophic waters compared to eutrophic states in beaver ponds. Pond creation as a management strategy or product of road construction may put western toad populations at risk of decline in the foothills of Alberta.

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DOES MULTIPLE PATERNITY INCREASE WITH FEMALE SIZE IN THE COMMON MAP TURTLE (Graptemys geographica)?: A WORK IN PROGRESS

Carine Verly¹, Gregory Bulté², Gabriel Blouin-Demers^3
1 Department of Biology, University of Ottawa, 150 Louis Pasteur, Ottawa, ON, Canada, K1N 6N5. Telephone: (613) 562-5800-2574. Fax: (613) 562-5486. E-mail address: [email protected]
²Department of Biology, University of Ottawa, 150 Louis Pasteur, Ottawa, ON, Canada, K1N 6N5. Telephone: (613) 562-5800-2574. Fax: (613) 562-5486. E-mail address: [email protected]
³Department of Biology, University of Ottawa, 150 Louis Pasteur, Ottawa, ON, Canada, K1N 6N5. Telephone: (613) 562-5800-6749. Fax: (613) 562-5486. E-mail address: [email protected]  

In general, larger females can produce more and/or bigger offspring. It has also been shown that larger offspring survive better. Therefore, larger female map turtles should be more attractive to males. If males incur non-trivial costs of mating, such as missed opportunities or sperm limitation, they should mate preferentially with large females. Accordingly, multiple paternity should be more common in larger females. To test this prediction, we captured 34 gravid females spanning the full size range of reproductive females and induced egg laying with oxytocin. We then collected blood samples from > 250 hatchlings for paternity analyses (the number of sires will be deducted from the paternal alleles at 5 microsatellite loci). Results will be compared to other turtle species for which multiple paternity has been assessed, in light of their mating systems.

En général, les plus grosses femelles produisent plus et/ou de plus gros rejetons. Il a également été démontré que les plus gros rejetons ont une meilleure chance de survie. Pour ces raisons, les mâles Tortues Géographiques devraient être plus attirés par les plus grosses femelles. Si les mâles encourent des coûts de reproduction élevés, tels des pertes d'opportunités d'accouplement ou une limitation dans la spermatogénèse, ils devraient s'accoupler préférentiellement avec de plus grosses femelles. Par consequent, la paternité multiple devrait être observée plus fréquement dans les couvées pondues par des grosses femelles. Nous avons capturés 34 femelles gravides pour tester cette prédiction. La ponte à été induite en laboratoire à l'aide d'oxytocine et nous avons prélevé des échantillons sanguins sur plus de 250 rejetons pour effectuer des analyses de paternité (le nombres d'allèles présents à 5 loci de microsatellites permettront de déduire le nombre de pères par couvée). Les résultats seront comparés aux autres espèces de tortues chez lesquelles des études de paternités multiples ont été effectuées et ce en lumière de leur système de reproduction.

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LOCAL AND REGIONAL SCALE HABITAT SELECTION BY WOOD TURTLES (Glyptemys insculpta) AT THE NORTHERN LIMIT OF THEIR RANGE / SÉLECTION D`HABITATS PAR LA TORTUE DES BOIS (Glyptemys insculpta) SUR L`ÉCHELLE LOCALE ET RÉGIONALE AU NORD DE SON AIRE DE RÉPARTITION

Pamela Wesley¹ and Dr. Ronald J. Brooks^2
1Department of Integrative Biology University of Guelph, Guelph, ON, N1G 2W1, Tel: (519) 824-4120 x.58360, Fax: (519) 767-1656, Email: [email protected]
²Department of Integrative Biology, University of Guelph, Guelph, ON, N1G 2W1, Tel: (519) 824-4120 x.53944, Fax: (519) 767-1656, Email: [email protected]

Wood turtles (Glyptemys insculpta) are declining throughout their range, largely as a result of habitat loss. Previous research has focused predominantly on studying movement patterns and habitat use/selection by wood turtles on the "local" scale. This study aims to identify "local" and "regional" scale habitat features selected by wood turtles at the northern limit of their range, as well as to determine the most relevant scale(s) of consideration with respect to resource management for wood turtle conservation. Local scale habitat selection by individual turtles during their active season is investigated by means of radio-telemetry. Regional scale habitat selection by wood turtle populations is studied through surveys of inhabited and uninhabited stream reaches. Logistic regression and Akaike's Information Criterion (AIC) will be used to develop and evaluate a number of potential habitat selection models at both scales. Beyond identifying environmental features significant to the wood turtle, successful models resulting from the landscape scale study may also be used to map potential wood turtle habitat that has not yet been identified.

La tortue des bois (Glyptemys insculpta) décline à travers son aire de répartition, en grande partie dû à la perte de son habitat. Jusqu'à présent, la recherche s'est concentrée sur les patrons de mouvement et sur l'utilisation ou la sélection d'habitats sur l'échelle locale. Cette étude a pour but d'identifier les caractéristiques d'habitat choisies par la tortue des bois sur l'échelle locale ainsi que sur l'échelle régionale. De plus, cette étude vise à déterminer la/les échelle(s) pertinente(s) à la gestion des ressources par rapport à la conservation de la tortue des bois. La sélection d'habitats par des individus à l'échelle locale a été étudié par moyens de radio-télémétrie, tandis que la sélection d`habitats à l'échelle régionale a été étudié par moyens de recherches faites sur des cours d'eau habités et inhabités par des populations de tortues des bois. La régression logistique et �Akaike`s Information Criterion� seront utilisés afin de développer et d'évaluer plusieurs models sur chaque échelle. En plus de pouvoir identifier les caractéristiques d'habitat de valeur à la tortue des bois, les models pourront être utilisés afin d'identifier de nouvelles régions (non connues) composées d`habitat convenable à cette espèce.

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DOES FOREST HARVESTING CREATE OR DESTROY AQUATIC AMPHIBIAN HABITAT?

Elke Wind
E. Wind Consulting. 348 Machleary St., Nanaimo, BC V9R 2G9 , 250-716-1119, [email protected]

Amphibians utilize a variety of lentic habitats for breeding, including small, seasonal ponds. However, current legislation in British Columbia does not provide protective measures for small wetland habitats less than 0.25 to 1 ha, depending on their location within the province. Island Timberlands (formerly Weyerhaeuser) utilizes variable retention harvesting methods so that small tree patches are often retained around small, ephemeral ponds. As part of the Forest Project, we initiated a pre- and post-harvest study in 2004 to investigate the effectiveness of retaining buffers around small ponds at three forest sites containing 70+ ponds. The three treatments included: normal buffer width (1 tree width), double buffer width ( 2 tree widths), and unbuffered. At all ponds, the hydroperiod, drying rate, and amphibian species presence and larval development were recorded regularly. In Year One (2004), all sites and ponds were unharvested. In Year Two (2005), one site was harvested using patch retention methods and two remained forested but roads were put in. In Year Three (2006), the remaining two sites will be also be harvested. The ponds were highly variable in their water depths, hydroperiods, vegetative cover, searchability, and presence of amphibian species. In 2004, all ponds dried by late July as it was a dry spring and summer. In contrast, spring 2005 was wet and the ponds retained water until late August, especially those in the harvested site where water levels rose significantly. All three amphibian species returned to breed in ponds at the harvested site in 2005 (Long-toed salamander, Red-legged frog, and Pacific Chorus frog). Evidence suggests that Pacific Chorus frogs may be attracted to more open canopy ponds, potentially using roads as dispersal corridors, as they were common throughout the harvested site in 2005 and frequently observed breeding at ponds near roads in the two unharvested sites in 2005. Metamorphosis was confirmed at more sites in 2005 than in 2004.