Congratulations to the winners of the student awards from this year's AGM.
|l`Année:||Lauréates / Lauréats:||Title and Abstract:|
University of Toronto
|Titre: Genotypes and ghosts - comparative landscape genetics of a northern turtle community|
Auteurs: Christina M. Davy and Robert W. Murphy
Résumé: Conservation and landscape genetics analyses of reptiles often assume that related species will respond to factors which can influence their genetic structure (for example, population fragmentation) in a similar way. There are many conservation genetics studies of individual snake, lizard or turtle species, but data from multiple species are not often integrated. We use landscape genetics analyses to investigate variation in genetic population structure among three turtle species with differing behaviours, life history strategies and degrees of endangerment and population fragmentation. Using microsatellite genotype data from Spotted Turtles, Blanding’s Turtles and Snapping Turtles we test hypotheses about the genetic effects of population fragmentation on these three species. We also use standard landscape genetic analyses to test hypotheses about the relative influence that major landscape features in southern Ontario have had on the population structure of each species and discuss important similarities and differences between them.
|2011||James E. Paterson|
Pamela Rutherford with James
|Titre: Hatchling habitat selection and survivorship in two sympatric turtle species (Glyptemys insculpta and Emydoidea blandingii)|
Auteurs: James E. Paterson, Brad Steinberg, and Jacqueline D. Litzgus
Résumé: The small size, soft shell, and limited mobility of hatchling turtles may cause differences in susceptibility to predation and habitat selection as compared to adults of the same species. However, until recently, technological limitations and the cryptic nature of hatchling turtles have constrained our understanding of their ecology. We studied survivorship, behaviour, and habitat selection of 45 hatchling Blanding's turtles (Emydoidea blandingii) and 48 hatchling wood turtles (Glyptemys insculpta) from emergence to overwintering in 2009 and 2010 using radio telemetry in Algonquin Provincial Park, Ontario. Turtles were captured as they emerged from caged nests in the fall, outfitted with radio-transmitters, and tracked every 1-3 days until they died or until October when all living hatchlings were at overwintering sites. Habitat selection was studied at two spatial scales: coarse scale macrohabitat selection and fine-scale microhabitat selection. The mortality rate was high with 42 % of E. blandingii, and only 11 % of G. insculpta surviving to winter. Both species showed evidence of macrohabitat selection and used habitats surrounding nests non-randomly. Based on paired logistic regression models, both species also showed evidence of microhabitat selection, and important variables in the models differed between species. Hatchling G. insculpta were more likely to select microhabitats with cooler temperatures and less leaf litter, whereas E. blandingii were more likely to use sites with more groundcover and woody vegetation. These data suggest that post-emergent hatchlings select habitat as they disperse from nests. Hatchling habitat preferences need to be considered in recovery and management plans for these species at risk.
|2010||Marchell G. Coulombe |
Biology Department, Acadia University
|Titre: Conservation genetics of the wood turtle (Glyptemys insculpta) at the north-eastern limit of its range. |
Auteurs: Marchell G. Coulombe, Steve Mockford, Tom B. Herman.
Résumé: Within conservation biology, there is increasing impetus for genetic analyses in species conservation and management. Population genetics are often used to resolve taxonomic uncertainties and relationships within threatened populations and to detect declines in genetic diversity, especially within fragmented populations. The wood turtle (Glyptemys insculpta) is a vulnerable species occupying a disjunct range throughout north-eastern North America. Wood turtles face a diversity of threats, primarily due to habitat loss, and recent studies indicate wood turtle populations are experiencing a steady decline. Although wood turtles have been well described in other jurisdictions, little is known about wood turtle ecology in Nova Scotia, Canada. The wood turtle is one of four indigenous freshwater turtle species found in Nova Scotia, and is generally well distributed throughout the province. While a number of field studies have focused on describing wood turtle ecology, relatively no information exists on the population genetics of this species. The goal of this study is to describe the genetic population structure of the wood turtle in Nova Scotia, at the north-eastern limit of the species' range.
|2009||Megan L. Rasmussen |
Megan with Bruce Pauli
|Titre: Site fidelity, individuality and scale of habitat selection may complicate the designation of spotted turtle habitat in Ontario. |
Auteurs: Megan L. Rasmussen* and Jacqueline D. Litzgus
Résumé: Designation of habitat for Species at Risk is an important step in the conservation of populations. This is especially true for species such as turtles whose extreme life histories do not allow them to respond quickly to recovery efforts. The Spotted Turtle (Clemmys guttata) is listed as Endangered in Canada. Spotted Turtles appear to be habitat generalists across their range, but specialists within each population. These factors complicate the creation of basic habitat assessment and protection guidelines, even over relatively small geographical areas. This study documents habitat selection and use of overwintering and nesting sites in a large population of Spotted Turtles on Lake Huron, Ontario. Individual turtles (N = 15) were located regularly from April 2007 until April 2009 using radio telemetry. Based on multi-scale compositional analyses, individuals selected habitats for their home range and within the home range, and the ranking of preferred habitat types depended on the scale of study. Seasonal shifts in habitat selection were observed. Despite shifting macrohabitat types, microhabitat use did not vary by season. Females were more likely to choose areas with more available cover from June - August compared to males. Nesting sites were variable, and females showed fidelity to substrate type rather than a specific location. Overwintering site choice was also variable, and most individuals showed high fidelity to an overwintering location. Up to 16 individuals were found within one overwintering site. Based on the results of this study, we suggest that microhabitat characteristics should be the focus when describing Spotted Turtle habitat. The variability and individuality apparent in habitat selection (especially nesting and overwintering sites) complicates the designation of Spotted Turtle habitat in populations that have not been intensively studied.
|2008||Marie-Pier Prairie |
|Titre: Predicting recruitment success in amphibians in a forest remnant in southern Québec. |
Auteurs: Marie-Pier Prairie, David M. Green
Résumé: Estimates of amphibian abundance make an implicit assumption that the most easily observable individuals, usually breeding adults, correlates with breeding success, i.e. recruitment. We assessed how well the occurrence of metamorphosing individuals could be predicted from surveys of breeding adults, eggs or tadpoles. Surveys of calling adults, egg masses, dip-netting and funnel trapping surveys, and time-restricted searches, were performed at 24 breeding sites in a 467-hectare forest remnant in southern Québec, Canada. Four pond-breeding amphibian species, Rana sylvatica, Ambystoma maculatum, Bufo americanus, and Pseudacris crucifer were studied in 2006 and 2007 in order to determine how well the occurrence of each stage of the life cycle predicts occurrence of the next. Jaccard`s similarity indexes, contingency tables and logistic regression were used to evaluate which stage(s) were the most reliable indicators predicting recruitment success. The detected occurrence of calling or breeding adults was a very poor predictor for recruitment success, whereas the detection of eggs and tadpoles were sometimes included in the best logistic regression models predicting recruitment success although they did not contribute substantially to explain variance in the detection of metamorphs. Numbers of adults and egg masses found were variable among sites and between years, and were positively correlated only for wood frogs in 2006. Our results indicate that monitoring protocols for pond-breeding amphibians via calling surveys or egg mass countsmay be poor predictors of recruitment success and, therefore, of amphibian abundance at local scales.
|2007||Jeffrey R. Row |
|Titre: Genetic diversity and gene flow within and between Eastern Foxsnake (Elaphe gloydi) populations across Ontario. |
Auteurs: Jeffrey R. Row*, Anna Lawson, Carrie A. Mackinnon, Ronald J. Brooks, and Stephen C. Lougheed
Résumé: Human activities, most notably habitat destruction, have led to the decline in size, number, and extent of populations for many species. As a consequence, many populations suffer from reduced genetic diversity, which can lower reproduction and survival rates and also may reduce the ability of populations to adapt to changes in the environment. Eastern foxsnakes are a globally threatened species with a very limited range, approximately 70% of which is contained within 3 regional populations (eastern shore of Georgian Bay, Essex County and Norfolk County) in Ontario. From 2003 to 2007 we acquired and collected > 600 blood samples from each of the 3 regional populations and ~10 local sub-populations. Using these blood samples and 15 hyper-variable microsatellite loci we determined that a significant portion of the genetic diversity was conserved within the regional populations (~25%) and within the local sub-populations (~15%). Contrary to our prediction, populations in the heavily fragmented Essex County had much higher levels of genetic diversity than populations in Georgian Bay and Norfolk County. All three regional populations were significantly differentiated (p < 0.001) and local subpopulations within Georgian Bay and Essex County were significantly differentiated at relatively fine scales (~ 50 km). Further research and analysis will identify landscape features that promote and or impede gene flow within and between populations and determine the scale at which populations are organized.
|2006||Julie Lee-Yaw |
Julie with Bruce Pauli
|Titre: Evidence for cryptic lineages and range expansion from northern refugia in the Wood Frog, Rana sylvatica |
Auteurs: Lee-Yaw, J.A*, J.T. Irwin*, and D.M. Green*
Résumé: Although the post-Pleistocene range dynamics of recolonizing amphibians in North America are increasingly better understood, recolonization of the most northern regions and the impact of southern refugia on patterns of genetic diversity in these regions are not well reconstructed. Here we present a phylogeographic history of the widespread and primarily northern, wood frog (Ranasylvatica). We surveyed 551 individuals from 116 localities across the species` range for a 650b.p. region of the NADH dehydrogenase subunit 2 and tRNATRP mitochondrial genes and anadditional 45 individuals for a 700 b.p. fragment of cytochrome b. Our phylogenetic analyses revealed three distinct clades corresponding to eastern, Maritime and western populations. Phylogeographic patterns within each of these clades were both similar and distinct from patternsfound in other species. Specifically, we find evidence to corroborate eastern refugia located in the southern Appalachians near present-day North and South Carolina and in the interior plains in thelower Ohio River Valley. Current Maritime populations appear to have been colonized from the coastal refugium. However, a more northern refugium located in the Appalachian highlands appears to have been source for most other northeastern wood frog populations. Rana sylvaticapopulations in the Great Lakes region all appear to have been derived from a western refugiumthat was likely located in present-day Wisconsin. This refugium also appears to have been sourcefor populations in the species` expansive northwestern range since we find no evidence tosupport additional, more western refugia.
|2005||Brennan Caverhill |
Brennan (R) with Dave Cunnington
|Titre: Linking science and stewardship through public education with the Nova Scotia Blanding's turtle (Emydoidea blandingii) |
Auteurs: Brennan Caverhill and Tom Herman
Résumé: The Nova Scotia (NS) Blanding`s turtle population complex is small, disjunct, and subject to unique threats, which contribute to its nationally "Endangered" (COSEWIC) and provincially "Endangered" (NSESA) status designations. The NS complex provides a diverse array of conservation opportunities and mechanisms; of its three known populations, one occurs in a national park (Kejimkujik - KNP), one in a combined provincially and privatelyprotected area complex (McGowan Lake - ML), and one in a working landscape dominated by small private landholdings (Pleasant River - PR). Although habitat in KNP and ML are effectively protected from direct human disturbance, PR is not, which makes it an important target for public education and stewardship activities. We broadly define stewardship as an ownership of responsibility on the part of all members of the public (not justland owners), while public education includes not only formal presentations but also random field-encounters thatinvolve an information exchange between researchers and community members. Intensive research over the past four years (2002-2005) in Blanding`s turtle habitat surrounding the rural community of Pleasant River has resulted in the convergence of science and stewardship, which has been facilitated by effective public education and outreach tactics. Providing education FOR the people has resulted in supportive stewardship action FROM the people, which has been invaluable to our science and management decisions in the area.
|2004||Constance Browne |
Constance with Dave Cunnington
|Titre: Population declines of freshwater turtles in Point Pelee National Park |
Auteurs: Constance L. Browne* and Stephen J. Hecnar
Résumé: Turtles are of conservation concern worldwide and in Canada 8 of 10 freshwater turtles are considered to be at riskby COSEWIC. We examined the status of turtle populations in Point Pelee National Park in 2001/2002. Point Pelee is located in southwestern Ontario and historically has been the location of greatest turtle diversity in Canada. Recently, park staff have been concerned of turtle population declines. Our objectives were to examine the status of turtle populations and the effects of nest predation and road mortality. We used mark-recapture/trapping and intensive visual surveys to estimate population sizes and structure. Captured turtles were marked, measured, sexed,and released. We examined age structure by using carapace length as an indicator of age and compared data from 1971/1972 to 2001/2002. We examined the effects of nest predation and road mortality using population models with Ramas Ecolab. Nest predation rates were estimated by locating turtle nests and monitoring them daily to determine what percent became predated. Average annual road mortality rates were estimated using 18 years of road mortality data. We captured a total of 1599 turtles of 5 species. Blanding`s (Emydoidea blandingii) and snapping(Chelydra serpentina) turtles have experienced a clear shift towards larger size classes since 1972, which suggests juvenile recruitment into these populations is limited. Predation rates on nests ranged from 62.5% to 100% among areas. Road mortality models suggested that road mortality alone could cause population declines in Blanding`s turtles but not likely in snapping and painted (Chrysemys picta) populations. However, high nest predation levels are a much more serious risk to these populations. Nest predation of 70% predicted serious declines in Blanding`s populations but not snapping and painted populations. However, predation rates of 90% cannot be sustained by any species.
|2003||Sara L. Ashpole ||Titre: ASSESSMENT OF PESTICIDE EXPOSURE AND EFFECT IN AMPHIBIANS USING AGRICULTURAL HABITAT, SOUTH OKANAGAN, BRITISH COLUMBIA |
Auteurs: Sara L. Ashpole, Christine A. Bishop, John Elliott and Laurie Wilson
Résumé: Many species of amphibians are the subject of serious conservation concern in Canada and elsewhere due to habitat loss and exposure to other anthropogenic stressors especially pesticide exposure. The Okanagan valley in BC is an intensive agricultural area where 80% of the natural wetlands and riparian areas have been developed. Yet due to the southerly location of this area, it also supports abundant and diverse amphibian populations that are known to use ponds and irrigated areas in agricultural lands. In the Okanagan valley, nationally endangered species (Tiger Salamander, Ambystoma tigrinum), threatened species (Great Basin Spade Foot Toad, Spea intermontana), and species of special concern (Western Toad Bufo boreas) still occur. Furthermore, the Northern Leopard Frog (Rana pipiens) has been extirpated from the South Okanagan for no known reason. Due to the presence of many rare species and the high potential for exposure to pesticides and the lack of natural habitat, it is necessary to assess the risk of amphibian populations to the impact of pesticides. In 2003, twenty-four ponds were surveyed for breeding adults and larval productivity to determine relative population densities. Habitat assessment, water chemistry, and sediment sampling was conducted at each site. All moribund and road-killed amphibians found in agricultural areas are to be analyzed for pesticides.
|2002||Virginia A. Abbott |
|Titre: Amphibian distribution in Northwestern Ontario: assessing the role of local habitat and landscape characteristics |
Auteurs: Virginia A. Abbott, Shannon Maronese and Stephen J. Hecnar
Résumé: Habitat loss is considered a serious threat to many amphibian populations, and has been implicated as a major cause of global amphibian decline. As a result of their dual-lives, and dependence on water, both aquatic breeding habitats and their adjacent terrestrial habitats are crucial for the persistence of amphibian populations and communities. From either ecological or conservation perspectives it is important to understand which habitat components may influence the occurrence of amphibians at a breeding site. We assessed the status of amphibians using presence/absence surveys, and investigated amphibian distribution and species richness with respect to local habitat and landscape characteristics at ponds. We repeatedly surveyed 69 ponds in Northwestern Ontario from 2001 to 2002. Local habitat characteristics evaluated include pond area, perimeter, volume, depth, bank slope, pH, conductivity, turbidity, and the structure of vegetation within and along the edge of each pond. Landscape variables were assessed using GIS software, and included forest cover, number of wetlands, lakes and rivers, length of paved and unpaved roads, landscape heterogeneity, and elevation within a 2 km radius of each pond. We observed ten species of amphibians throughout this study. Species incidence at all our ponds were as follows: Pseudacris crucifer (100%), Rana sylvatica (98.6%), Bufo americanus (91.3%), P. triseriata (66.7%), R. septentrionalis (63.8%), Hyla versicolor (47.8%), R. clamitans (26.1%), R. pipiens (13%), Ambystoma laterale (13%), and A. maculatum (11.6%). Species richness over the two-year period was approximately 4.6 ± 0.14, and preliminary multiple regression analyses suggest that species richness is associated with depth, volume, pH, conductivity, and emergent and edge vegetation. Furthermore, preliminary logistic regression analyses suggests that each species is associated with a different set of habitat characteristics, except P. crucifer and R. sylvatica which were present in all ponds. These results will enable us to predict species presence at a breeding site, as well as crucial aquatic and terrestrial habitat components for amphibians.
|2001||Jean-François Desroches |
|Titre: Characteristics, movements, and health of a Western Chorus Frog (Pseudacris triseriata) population at a breeding pond in southwestern Québec|
Auteurs: Jean-François Desroches and Martin Ouellet
Résumé: We studied a population of Western Chorus Frogs (Pseudacris triseriata) at a breeding pond in southwestern Québec. A total of 951 captures of 842 adults was made between 19 April and 28 May 2001, using a 225 meter-long drift fence surrounding the pond. Frogs were measured, weighed, examined for diseases and deformities, marked, and released. The majority of individuals (97.1% or 540/556) arrived from day 0 to 7, with a peak (57.9% or 322/556) at day 3. Almost all frogs (99.5% or 393/395) left the pond from day 15 to 39, with a peak on day 15 (44.1% or 174/395). The sex-ratio was biased in favor of males (489 males: 353 females). For males (N=54) and females (N=49) that were recaptured, the mean duration in the breeding pond was 24.2±10.3 days and 20.2±9.7 days, respectively. Including frogs caught after the breeding season, a total of 864 adults was examined (499 males and 365 females). Females were slightly larger (SVL=25.48±0.08mm, N=365; weight=1.08±0.02g, N=197) than males (SVL=24.66±0.07mm, N=498; weight=0.95±0.01g, N=253). The tibia length was correlated with the SVL for both sexes (r2=0.711, N=503, p< 0.001). Overall, 54 (6.3%) presented body scars or traumatic digit amputations and 22 (2.5%) had minor anomalies such as brachymely, syndactyly, or eye color variant (black eyes). Chytridiomycosis was diagnosed in 54 of 142 (38.0%) adult P. triseriata sampled during the breeding period. Chytrid infection is enzootic in this apparently healthy population and has not yet been associated to any cases of disease or mortality.
|2001||Sara Ashpole |
University of Guelph
|Titre: The effect of handling stress on deformity rate and hatching success in the Common Snapping Turtle, Chelydra serpentina serpentina, from Algonquin Provincial Park and Hamilton Harbour, Ontario Canada: do traditional laboratory incubation methods mirror naturally nesting populations?|
Auteurs: Sara L. Ashpole, C.A. Bishop and R.J. Brooks
Résumé: Over the years, eco-toxicology field research conducted on snapping turtles has supported that both hatching success and deformity rates are sensitive biomarkers of persistent organic pollutants in the environment. In this study, we examined two sites with contrasting levels of contaminants, Hamilton Harbour (heavy industry with moderate to high levels of contaminants) and Algonquin Provincial Park (very low to non-detectable levels of contaminants) and the contribution of handling stress on embryo development. Handling stress can include: the physical removal of developing embryos from a maternally selected nest into an artificial environment; the transportation of embryos to the laboratory; and the incubation of embryos at a constant and very unnatural temperature. We hypothesise that if undisturbed naturally nested embryos develop in the same manner as those under laboratory conditions, then we would predict that their hatching success and deformity rates to be the same. To test this, our study was designed to compare undisturbed predator-protected natural nests with artificially incubated embryos. From both study sites, nests were either undisturbed and protected (N=10, Hamilton Harbour; N=7, Algonquin Park) or collected (N=15 from each site). One-third of collected clutch was redistributed into the following treatments: a predator protected artificial buried nest; and artificial incubation at both a male- and female-producing temperature, 25.0°C or 29.5°C respectively. Comparisons between treatments and the study sites are in progress and will be discussed at the conference.
University of Calgary
|Titre: Phylogeographic analysis of Ambystoma macrodactylum: post-glacial tracks and resultant genetic diversity |