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.

Phylogeographic perspectives increasingly influence priorities in conservation, providing insight into such areas as the geographic distribution of evolutionary independent population segments (ESUs), the location of contact zones, or the presence of cryptic species. Further, comparisons across co-distributed species can both clarify the roles of history and ecology in shaping present-day patterns of genetic diversity and help determine conservation strategies for regional biotas. For example, regions containing distinct ESUs across a range of species may be candidates for high conservation priority because each houses a significant proportion of the evolutionary legacy of considered taxa.

To this end, we compared phylogeographic patterns in two evolutionarily and ecologically distinct anurans, spring peepers (Pseudacris crucifer ) and bullfrogs (Rana catesbeiana) using mitochondrial DNA sequences. For both species we found pronounced and roughly concordant phylogeographic structure with evidence for historical fragmentation, expansion and isolation by distance. Our analyses further suggest that: 1. south-central Ontario is a suture zone, where long-separated lineages have come into secondary contact following the last Pleistocene glaciation, approximately 10-15,000 ybp., and 2. in a Canadian context, extreme southern Ontario may be a conservation priority not only because it contains herptofauna found nowhere else in the country, but also because it captures a significant portion of the phylogenetic history of traditionally regarded "species."

The European Wall Lizard was introduced in Victoria in the late 1970's. These lizards are well established at the original introduction site and at a minimum of two other sites. Dispersal appears to be through diffusion and jump-dispersal, similar to what has occurred in an introduced population of wall lizards in Cincinnati, Ohio. The areas inhabited by wall lizards in Victoria are disturbed, for example a power line and roadsides. The effects of wall lizards, if any, on the native Alligator lizard (Elgaria coerulea) are unknown. Differences between the two include their general behavior and modes of reproduction; their diets appear to be similar. Alligator lizards and wall lizards are known to occur together in Victoria. Analyses of habitat use and behavior experiments aim to identify any potential effects of wall lizards on alligator lizards.

In 2002, this group formed to draw up recovery plans for a suite of reptile and amphibian species in the south Okanagan. Currently, we are preparing recovery strategies for great basin gopher snake, tiger salamander, great basin spadefoot toad, night snake, and plan to write up a COSEWIC report for the new species Crotalus oreganus recently identified for BC. Our strategy is to prepare these strategies separately because that is how the species at risk system currently handles recovery plans, but to apply for funds for many of the species as a related group of animals sharing similar habitats. We are presenting our strategy in hopes that others in the country might try the same approach especially with the impending passing of the federal Species At Risk legislation.

Skeletochronology is a widely used histological technique to estimate age in amphibians and reptiles which exhibit cyclic patterns of growth. Currently, it is the most widely used method to estimate age in amphibians and ages derived from skeletochronology form the basis of demographic analyses in which survivorship, age at maturity, and age-specific growth and fecundity are calculated. Although the method has been widely used for more than 20 years, we are unaware of any study that has validated skeletochronological estimates using known-age specimens. We tested two hypotheses based on the assumption that skeletochronology does indicate age accurately and precisely (i.e. has high repeatability). We predicted that (a) estimated ages would be accurate, (b) that observers would detect the correct sequence in samples taken from frogs in consecutive years, and (c) that estimates of age or sequence would not be strongly biased by observer expectancy. Lastly, we tested for differences in accuracy between experienced and novice observers. Cross-sections of the second phalanx of the forelimb toes were histologically mounted, photographed and archived on CD�s so that visual projections could be enlarged on a screen to conduct counts of growth lines. Both experienced and inexperienced observers provided estimates significantly different from true age, had low success in determining the correct sequence of successive years of samples for individual frogs, and were significantly influenced by observer expectancy bias. Experience had no significant effect on observer performance. We conclude that skeletochronology is unreliable, inaccurate and essentially useless to estimate age in this population of bullfrogs.

Population data on the southern Ontario population of wood turtles (Clemmys insculpta) from 1988-2002 were combined with relevant life history parameters to test the hypothesis that this population is viable and to recommend management initiatives to ensure the population remains viable. In 1993, the Maitland population probably consisted of about 300 adults and juveniles, largely confined to two small streams. By 2002, the populations had declined to fewer than 100 individuals. Only 2 or 3 new turtles have appeared since 1993, hence the population in 2002 is only 30% of that in 1993 and all the turtles are 10 years older, most are older than 30 years. The decline was likely due to a poaching event that occurred in 1994 or 1995. A population viability analysis indicates that given typical age-specific rates of survival, age at maturity, fecundity, and sex ratio, this population will decline to zero in 50 years. Maximizing any single life-history parameter (e.g. raising survival of eggs to hatching to 100%) will not prevent extinction of the population within a few decades. If survival is maximized for all major life-history stages (egg, hatchling, juvenile, adult), the population could recover to 1991-93 levels in about 60 years. Without timely intervention by protecting nests, headstarting hatchlings to release as juveniles and protection of all turtles from collecting, the population will die out. Headstarting has not been tested in this species, but if it is not undertaken soon, prospects of success will be very dim.

Connie L. Browne and Stephen J. Hecnar
Lakehead University, 955 Oliver Road, Thunder Bay, ON. P7B 5E1
Telephone: 519-324-9079, Fax: 807-346-7796, Email: [email protected]

Point Pelee National Park (PPNP) was historically the location of greatest turtle diversity in all of Canada. Seven native species have been reported from PPNP: painted, snapping, Blanding's, map, stinkpot, spotted, and spiny softshell. However, like many other turtle populations worldwide, populations of many species at PPNP appear to be declining and some may already be extirpated. Our objectives were to determine the status of turtle species at PPNP and possible causes of declines. We conducted visual surveys and trapped turtles at 16 sites in 2001. We focused on 'hot spots' in 2002 to obtain more accurate population estimates. We also conducted extensive foot searches for species at risk in 2002 focussing on species not found in 2001. We trapped turtles using baited hoop, basking, and live traps, and by hand captures. Standard measurements, weight, habitat, and UTM coordinates of captured turtles were recorded and turtles were marked by notching the marginal scutes of their shell and painting numbers on their shells. We searched for nests in 2001 and 2002 and monitored half of all nests found in 2002 for predation. We marked 1596 individual turtles in 2001/2002 representing 5 of the 7 native species. Spotted turtles and spiny softshell were not found despite extensive search efforts. Populations of painted and snapping turtles still appear to be large but are significantly male-biased. Painted, snapping, map and Blanding's populations have significantly top-heavy age structures. The distribution of carapace lengths (age) when compared to data from 1972 suggests that there has been a significant shift toward older age classes for both snapping and Blanding's turtles. If this trend continues these populations can not be sustained. Nest predation (mostly by raccoons, skunk, and opossum) rates were 100% in some areas of the park. This high rate of predation appears to be at least partially responsible for the lack of recruitment into turtle populations at PPNP.recorded and turtles were marked by notching the marginal scutes of their shell and painting numbers on their shells. We searched for nests in 2001 and 2002 and monitored half of all nests found in 2002 for predation. We marked 1596 individual turtles in 2001/2002 representing 5 of the 7 native species. Spotted turtles and spiny softshell were not found despite extensive search efforts. Populations of painted and snapping turtles still appear to be large but are significantly male-biased. Painted, snapping, map and Blanding's populations have significantly top-heavy age structures. The distribution of carapace lengths (age) when compared to data from 1972 suggests that there has been a significant shift toward older age classes for both snapping and Blanding's turtles. If this trend continues these populations can not be sustained. Nest predation (mostly by raccoons, skunk, and opossum) rates were 100% in some areas of the park. This high rate of predation appears to be at least partially responsible for the lack of recruitment into turtle populations at PPNP.

Prairie rattlesnakes and bullsnakes make pronounced seasonal migrations from hibernacula along the South Saskatchewan River to summer foraging areas. These movements are strongly directional and many snakes traverse a road network adjacent to the river. Mortality of snakes arising from road traffic has been observed annually since research activities commenced in 1994, and recent acceleration of shallow gas development has resulted in increased road traffic. The biological factors, physical setting, and human activities which have made snake mortality on roads a management issue, and the conservation actions which have been initiated, are presented.

There are now 48 amphibians and reptiles on the Species at Risk list produced by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), a four fold increase over the past 10 years. This increase largely reflects the pace at which COSEWIC has been able to assess these species. Once the Species at Risk Act (Bill C-5), known as SARA, receives royal assent and is proclaimed, species listed by COSEWIC will receive legal protection at the federal level. SARA is currently in committee hearings before the Senate, having passed the Commons in May, 2002. After several previous attempts at endangered species legislation in the past several years, how SARA came to be written in its current form and finally passed is a story of compromises, frustrations, political deals, and procedural tricks. Once proclaimed, however, the law will directly or indirectly influence virtually all aspects of species conservation in the country. The genesis of the Bill in its current form and the species, particularly amphibians, it will affect will be discussed.

Fifteeen consecutive years of monitoring of Fowler's toads at Long Point, Ontario, from 1988 through 2002, has yielded accurate estimations of the numbers of toads present, relative numbers of juveniles and adults, recruitment, age structure, longevity, sex ratio, clutch size, and survivorship. The toads at this locality have undergone several cycles of population rise and fall related to variations in recruitment, immigration, and over-winter survival. Extensive mark-recapture data demonstrate that although the majority of toads move very little, about 2% may move surprisingly far. Over a year, the maximum distance between successive captures may exceed eight kilometers. Juveniles and adults disperse with equal propensity. However, the three extant localities of Fowler's toads in Canada are further apart than the minimum distance required for genetic cohesion via dispersal. Evidence from mitochondrial DNA control region sequences shows that there has been little historic genetic exchange among the localities along the northern shore of Lake Erie.

Growth of urban areas results in loss of habitat for wild species, but diverse species can persist in such landscapes, especially if remaining habitat patches are large. The valley of Sixteen-Mile Creek in Oakville, Ontario is a striking example of such a situation. Despite housing development to its edge, numerous species of native wildlife, both small and large, inhabit the valley. Among these are six species of snakes, including one (the water snake, Nerodia sipedon) apparently no longer found anywhere else in the Greater Toronto Area. The six species are distributed unequally along the valley�s length. For example, the water snake, although abundant, is confined to the southern part of the valley, which has had the longest exposure to urban development. Among key features that support this fauna are: 1. fairly limited development so far in the valley bottom, save for public walking paths;. 2. an abundance of cover, especially rocks. All six species are usually found under rocks, sometimes in aggregations of either single or mixed species. However, propensity to use cover varies within and among species as a function of body size. Size of rock used also is correlated with size of snake. Manipulation of this kind of cover is thus a potentially valuable management and restoration tool.

The Oregon spotted frog (Rana pretiosa) is Canada's most endangered amphibian with an average effective population size of 371 over four years of survey at three occupied sites. A recovery team was formed in 1999 and includes 15 individuals representing 12 organizations and/or branches of government. The team's long-term goal is to improve the Oregon spotted frog's long-term chances for survival and prevent its extinction, and to reclassify the species from endangered to threatened. A draft recovery plan is in place and suggests this species can be reclassified once 20 occupied sites with a total area of occupancy of 250 hectares and an average effective population size of 100 individuals at each site is established.

Recovery activities correspond with recovery objectives and fall under the general categories; survey, monitor, protect, populations, habitat, research, husbandry, species introductions, and education. Information resulting from specific recovery activities such as habitat creation and enhancement projects, radio-telemetry and habitat use study, annual monitoring, etc., is presented. A brief synopsis of funding sources is also presented.

It is widely accepted that many local amphibian populations fluctuate drastically. Numerous studies now also suggest that many amphibian species exhibit metapopulation dynamics. However, there are few studies of long-term spatial and temporal trends in amphibian communities. Furthermore, an unresolved debate in ecology concerns whether communities behave more as equilibrium or non-equilibrium systems. Determining whether amphibian communities are stable, and if so, the scales at which it applies, has important implications for conservation. We studied patterns of species richness, incidence, and turnover in 35 pond communities in southwestern Ontario from 1992 to 2002. We conducted repeated annual surveys at 35 sites to construct accurate local species lists that could be compared spatially and temporally. Since 1992, we observed 14 species and generally highly dynamic local populations. Some species were common (eg. Rana clamitans, Pseudacris crucifer) while others were extremely rare (eg. R. palustris, Ambystoma spp.). Only one species showed any trend in incidence with time; annual incidence of spring peepers rose monotonically from 62% to 97%. This increase appears to be the result of a drought-induced shift from temporary ephemeral ponds to more permanent bodies of water. Turnover at local sites was high (average 17%) but did not differ among years or show any trend with time. Although local (re)colonizations and extinctions appeared to be common, they tended to balance out at larger spatial scales. Despite the high turnover, local species richness (average 4.2 � 0.08) did not differ among years or show any trend with time. Since the mid-1800s southwestern Ontario has experienced much habitat loss and many local extirpations of amphibian populations have occurred. The region continues to be highly disturbed by intensive agriculture and urbanization. However, although the surviving fauna is highly dynamic, it appears to function as an equilibrium system and to be stable at the regional scale. Our studies emphasize the efficacy of using a metapopulation framework for understanding the dynamics of amphibians and highlight the fact that conservation efforts must operate at larger regional scales.

Eastern Ontario�s only lizard, the five-lined skink (Eumeces fasciatus) is found solely in two disjunct series of populations: southern Ontario (including Point Pelee National Park and Pinery and Rondeau Provincial Parks), and the southern Canadian Shield extending from Georgian Bay to St Lawrence Islands National Park. Most existing ecological data for these populations, including trends of decline, derive from long-term research in Point Pelee National Park. However, the conservation status of Canadian populations remains unclear; particularly as it pertains to genetic distinctiveness of southern and Shield populations and habitat usage of the latter. We have initiated and will discuss preliminary results from a study to address these data gaps using habitat data and tissue samples for 340 individuals from 11 populations.

Gross habitat features clearly differ tremendously between the southern and Shield populations. Southern Ontario populations are generally found within broadleaf deciduous forests with fertile soils and a relatively mild climate, while Shield populations occur in mixed deciduous/coniferous forest overlying acidic soil with patches of exposed granite outcrops. To see whether microhabitat features mirror these obvious large-scale habitat differences between northern and southern Ontario populations we used a series of 1m² quadrats to quantify proportion of different habitat elements (e.g. loose rock, lichen, leaf litter). Using a Classification and Regression Tree (CART) approach, we determined that in skink-occupied habitats loose rock cover is the single most important predictor of skink presence across Shield populations. This result parallels findings for southern Ontario where woody debris for cover was found to be an integral microhabitat feature (Hecnar and M�Closkey 1998).

For the genetic portion of our study, we have developed primers for a series of species-specific di- and trinucleotide microsatellites. We will use data from these high-resolution DNA markers and from mitochondrial DNA sequence to quantify the apportionment of genetic diversity across hierarchical levels, from within populations to range-wide, and will discuss the conservation importance of our preliminary findings.

Although most squamates at high latitudes are viviparous, the oviparous grass snake (Natrix natrix) almost reaches the Arctic Circle in Scandinavia. As part of a study of the reproductive ecology of this species, we have collected data on its general natural history at a site in southern England. Grass snakes are abundant at this site, but are fairly inconspicuous because of their colour, their frequent association with dense vegetation, and their rapid escape response. However, once caught, grass snakes usually exhibit some degree of death-feigning behaviour before attempting to escape again. Like most other natricines, grass snakes are strongly sexually dimorphic: females grow to larger sizes than males, have bigger heads, and have shorter tails. Prey consist mostly of anurans, especially the introduced Rana ridibunda, but other kinds of prey also are taken. Our work on reproductive ecology is still in the early stages, but grass snakes lay large clutches of small eggs that produce small offspring; natural nest sites are presently unknown at this site.

The northern leopard frog (Rana pipiens) was once a common and widespread species found throughout central and southern Alberta. During the late 1970s, the leopard frog experienced a dramatic decline over much of its historic range in Alberta. Today, existing leopard frog populations remain isolated and fragmented and are primarily restricted to the southern portion of the province. In 1996, the leopard frog was designated as "Threatened" under Alberta�s Wildlife Act.

In 1998, the Alberta Fish and Wildlife Division began to explore the feasibility of a leopard frog reintroduction project. In response to a minimal potential for the leopard frog to re-colonize formerly occupied areas of its range, a pilot reintroduction project was initiated in 1999 at the Raven Brood Trout Station near Caroline, Alberta. The project involved the captive rearing of leopard frogs from egg stage of development to metamorphosed frog.

The primary objective of the project is to strategically re-establish leopard frogs at pre-selected sites in the upper Red Deer River and North Saskatchewan River drainages. Over the course of the study, a total of three release sites have been selected. All captive-reared leopard frogs are marked with a Visual Implant Elastomer (VIE) tag upon metamorphosis, providing an externally visible identification mark. This tagging system allows for the assessment of the survival success at each release site and the ability to monitor the dispersal of released frogs. Different tag colors and rear foot combinations help identify the year of release for each frog.

In 2001, several leopard frogs released in previous years were located at the first release site near Caroline, representing the first occurrence of leopard frogs in that area in nearly 50 years. The following spring at least three leopard frogs were heard calling from a pond within the same release study area and one leopard frog egg mass was observed. Two unconfirmed leopard frog observations have been recorded, in 2002, from the second release site near Rocky Mountain House, Alberta. Leopard frogs were released at a third pilot release site near Red Deer Alberta in 2002. Over-winter survival success at this new site will be assessed in the spring of 2003.

Experiments were carried out to find the induced effect of organophosphate (malathion) and pyrethroid (cypermethrin) on the enzyme (cholinesterase) of Indian Garden Lizard Calotes versicolor Daudin. Two different concentrations 0.1 and 1% were used and the cholinesterase activity was estimated, in liver, kidney and brain. It was decreased up to 20 and 35% in liver, 27 and 54% in kidney and 8.7 and 38% in brain. In the case of malathion the decrease of cholinesterase activity was found as 30.27 and 66.97% in liver, 58.46 and 65.09% in kidney and 9.23 and 5.42% in brain, respectively.

The Jefferson salamander (Ambystoma jeffersonianum) is a member of the mole salamander family. It became nationally threatened in November 2000, warranting the development of a recovery plan within two years of its listing. Jefferson�s salamander is restricted to undisturbed, mature hardwood forests adjacent to fishless breeding ponds in southern Ontario. This habitat type is quickly disappearing. Development in existing habitats of this type, such as the Oak Ridges Moraine and the Niagara Escarpment, is now being challenged by the presence of Jefferson�s salamanders. Efforts are being made to find old and new Jefferson salamander populations for the purposes of drafting a recovery plan and to avoid developing over important breeding and migration habitat. Because they are very rarely observed, little is known about their population distribution and abundance. There are several reasons why finding and identifying Jefferson�s salamander can be problematic. The adults are very secretive, living in burrows and under forest debris, and can be found above ground for very limited periods of time throughout the year. Their involvement with other members of the Ambystoma genus in a unisexual hybrid complex complicates their identification. I will be presenting methodology used to find and identify A. jeffersonianum and members of the hybrid complex. Tips for identifying Jefferson�s salamander adults and egg masses from other members of the genus will be provided. Focus will be on field methodology, and early season versus late season field sampling techniques will be covered. Lab methodology (raising larvae and allozymes) will also be touched upon.

My students and I have been studying the reproductive biology of the red-sided garter snakes of Manitoba for 20 years. Reproduction in snakes seems to be dependent on the production and perception of sex pheromones. One question we are examining is how chemical communication systems evolved in vertebrates by examining both the diversity of chemical signals and the underlying physiological and endocrinological mechanisms involved in their production and expression. Using state-of-the-art chemical techniques, we have isolated, identified, and synthesized the first pheromone in a reptile, the red-sided garter snake, Thamnophis sirtalis parietalis. Pheromones are thought to be potent reproductive isolating mechanisms. We have been exploring the role of variation in the sex attractiveness pheromone system of the red-sided garter snake. We now know that with a single tongue-flick, a male garter snake can determine not only whether another snake is a member of its own species, but also if it is a male or female, a female from the male�s own den versus another den, a large female versus a small female (larger females produce more young), and whether a female is likely to reproduce this year or store his sperm for a following year. We are now expanding these studies to investigate a syntopic congener, the Western plains garter snake, Thamnophis radix.

Along with my collaborator, Rick Shine, our work on the garter snakes has examined fundamental questions such as male body size and mating success, size-assortative mating, mating plugs, female mimicry, antipredator tactics, thermoregulatory behavior, migratory behavior and others. Along with collaborators Steve Arnold, Mike Pfrender and Suzanne Estes, we are investigating the mechanisms by which female choice operates in this model species as well as the role inbreeding plays in the population genetics of these dens. We hypothesize that females may not be able to choose a particular male out of her hundreds of suitors; however, she may be able to choose how many times she mates. We are currently investigating the phenomenon of multiple mating, paternity analyses, and sperm competition in this species.

This research investigates the design of artificial snakes dens (ASD�s) as a means of providing a critical and limiting habitat resource for Red-sided garter snakes (Thamnophis sirtalis parietalis) in the Interlake region of Manitoba, Canada. Preliminary background research resulted in an understanding of: den requirements of the Red-sided garter snake, the characteristics of natural dens, and design precedents regarding artificial snake den design. This background research was used to determine a set of preliminary design guidelines for the design of ASD�s. Subsequently, these guidelines were used to facilitate an interdisciplinary, participatory and collaborative workshop on designs for ASD�s. The workshop focussed on preliminary designs for "landowner" and "research" artificial snake dens (LASD�s and RASD�s). The results of the background research and design workshop were used to propose conceptual designs for both a LASD and a RASD. Finally, based upon background research, the design workshop, and additional research, 38 design guidelines for LASD�s and an additional 11 guidelines for RASD�s were derived. The research suggests that the implementation of artificial snake dens could provide an important means of sustaining the Interlake population of Red-sided garter snakes. The research also suggests that the implementation of artificial snakes dens could be combined with opportunities for ecotourism and further research, particularly the formation of a National Centre for Herpetological Research.

Amphibians are exposed to endocrine-disrupting chemicals that may ultimately contribute to population declines. The current study addresses the effects of a known hormone mimic on aspects of anuran development. Ethynylestradiol is a synthetic estrogen commonly detected in domestic sewage effluents. A study lake was dosed with 17�-ethynylestradiol (EE2) at a mean concentration of 6 ng/L, in May to October 2001 (Experimental Lakes Area, NW Ontario, Canada). Tissue thyroid hormone concentrations were assessed in cage-reared green frog tadpoles (Rana clamitans) from the EE2-treated lake and two reference lakes. Mean T3 and T4 concentrations were not significantly different among lakes. Growth and development rates of cage-reared green frog tadpoles were not significantly different among lakes, whereas hatch success was lower (though nonsignificant) on the EE2-treated lake. Gonads of wild-caught mink frog tadpoles (R. septentrionalis) and cage-reared green and mink frog tadpoles were examined histologically. Low frequency of intersex was detected in caged (5.6%) and wild (1.6%) mink frog tadpoles from the EE2-treated lake, whereas no intersex occurred in tadpoles from the reference lakes. Few impacts of environmentally relevant concentrations of EE2 were observed for these anuran species.

In the past 100 years several reptile and amphibian species have become extirpated from Pelee Island, Ontario due to habitat loss, persecution, road kill, and undetermined factors. Although a generalization, it is common knowledge that wildlife needs area (large scale habitat) and more specifically within habitats a range of microhabitat features is necessary for life history functions. For the past seven years we have created/restored both macro and microhabitat features for snakes, turtles, toads, frogs and salamanders, in efforts to stop further decline. Large-scale habitats that we have restored include prairie/old field, savanna, scrub and forest. Within this large-scale mosaic we have built and tested several microhabitat features for reptiles and amphibians including hibernation sites, "hot rocks", ephemeral wet scrapings, nesting and basking structures. Our target species include blue racer, Eastern fox snake, Lake Erie water snake, smallmouth salamander, Blanchard�s cricket frog and American toad. We will present preliminary results from monitoring thus far and some brief plans and instructions on construction techniques.

Home to nearly 40 Species At Risk, Pelee Island, Ontario (4000 ha) also contains several unique Canadian reptiles and amphibians including the Lake Erie water snake, blue racer, smallmouth salamander, Blanchard's cricket frog (hopefully), as well as being the home of Canada�s southern most human community. The 2003 CARCNET Conference will be held on Pelee Island (September 10 to 13) and the meeting will dovetail with the 3^rd Annual Pelee Island Winery Endangered Species Festival (ESF) (September 14, 15). ESF is hosted by the Wilds of Pelee Island, a recently established Outdoor Centre for Conservation with support from the local Heritage Centre and the Pelee Island Winery. ESF was established for several reasons including the simple act of celebrating a legacy of diverse plant and animal life. Local residents and visitors are invited to experience and take pride in our rich natural life history, to learn more about our community, to laugh (at a comedy performance), to get active out-of-doors and to be artistic. We also acknowledge that small, rural communities, especially islands, in many respects share some characteristics with endangered species: small population size and isolation. The majority of Canadians live in cities and thus many are not connected with rural issues and lifestyles. Additionally, a measure of ESF�s success is the calculated amount of money raised for local businesses and charities, which gives more credence to supporting natural area and species conservation. This talk will focus on the benefits of strengthening communities for improved conservation measures for reptiles, amphibians and other taxa, including other vertebrates, insects, etc. Efforts towards strengthening a multitude of community needs, results in positive outcomes for individuals, groups of people, and the environment.

The growing array of wildlife protection acts is forcing Canadian biologists to identify 'critical habitat' for endangered species. However, we currently lack any form of guidance that would encourage a consistent and scientifically defensible approach to this complex task. The development and application of such guidance would serve biodiversity conservation by promoting even treatment across taxa and geographic regions. Furthermore, guiding principles would increase the likelihood that valuable populations would be targeted and that functional, biologically significant parcels or networks of critical habitat would be identified. In general, critical habitat should contribute to the conservation of diversity, with particular recovery and population viability objectives differing among species. Given this, the identification of critical habitat might be best informed by a combination of phylogenetic, ecological, and evolutionary perspectives. A phylogenetic perspective would tend to prioritize the most divergent populations for protection and recovery action. An ecological viewpoint might emphasize support systems for the preservation of current diversity. Finally, an evolutionary perspective would value populations that maximize the potential for future evolution. Case studies of endangered snakes will be presented to illustrate how these complimentary viewpoints might be employed to guide critical habitat designations.

Pollutants such as 4-octylphenol, an industrial chemical byproduct and estrogen mimic, pose a serious threat as an endocrine-disrupting agent to humans and wildlife. Our study examines environmentally relevant concentrations of water-born octylphenol exposure to the snapping turtle (Chelydra serpentina serpentina). We hypothesized that hatchling snapping turtles exposed to octylphenol would exhibit poor neuro-behavioural responses, such as reduced feeding and poor motor skills. Six clutches of snapping turtle embryos from Algonquin Provincial Park (a �pristine� reference site) were naturally incubated and excavated for laboratory studies 3 weeks prior to hatching. A sub-sample of embryos (N_t= 84) from each of the 6 clutches was randomly assigned to three treatments. The number of turtles used per treatment type include: negative control (well-water) N = 24, positive control (17ߖestradiol) N = 30, and treatment (4-octylphenol) N = 30. The �righting-response� and the �predator-response� were chosen as neuro-behavioural indicators. Beginning at 4 weeks post-hatch, body weight (� 0.1g) was measured biweekly with neuro-behavioral responses weekly. Treatment exposures were initiated on week 9 and ended at week 12. Body weight was also measured at 3 and 6 months post-hatch after which a sub-sample was sexed by gonadal inspection. For the righting-response, no differences within treatments were observed in the time from latency to righting and in time to complete righting. Comparisons between treatments showed that turtles righted faster when exposed to estradiol. Results are not yet available for the �predator response� and the effect of sex. The octylphenol treatment had induced higher growth rates when compared to the control treatment. Growth following estradiol exposure did not differ from either the octylphenol or control hatchlings. Our data suggest that, at this exposure level, octylphenol did not exhibit effects on neuro-behavioral responses like those induced by estradiol. In contrast, octylphenol induced growth and appears to be a growth promoter.

The Narcisse Snake Dens, with four active hibernacula, is internationally renowned as a unique natural phenomenon representing the largest concentration of snakes in the world. In the spring, following breeding, red-sided garter snakes (Thamnophis sirtalis parietalis) disperse to spend the summer feeding in marshes and meadows. Snakes return to the dens in late August and early September. A significant fall migration crosses Provincial Trunk Highway (PTH) # 17 immediately to the west of the Narcisse Snake Dens. Each fall passing motorists run over and kill as many as 20,000 snakes within this migration corridor. Manitoba Conservation embarked on a program of testing various mortality mitigation techniques with only limited success. In December 1998, the Narcisse Snake Mortality Advisory Group was formed to further study the snake mortality problem and develop a plan to deal with it in an effective and feasible manner. Shortly after the fall 1999 season, the advisory group was approached by a number of Manitoba Hydro employees who were familiar with the snake mortality problem on PTH #17. They felt that a solution might be achieved by installing 25 � 30 centimeter tunnels under the highway using the Corporation�s horizontal boring equipment. After considerable discussion and planning, a co-operative partnership was forged to test the effectiveness of these smaller sized tunnels. Manitoba Hydro staff, with the assistance of a number of businesses and organizations, has since 2000 installed in total 12 pipes at various locations in the snake migration corridor. Drift fences have been installed to direct snakes to these tunnels, as well as an existing culvert. The effectiveness of the snake tunnel system has been monitored by capturing and counting snakes as they migrate through the tunnels. Through the cooperative efforts of Manitoba Hydro, Centra Gas and other project partners, snake mortality on PTH #17 has been reduced by approximately 75%.

Understanding habitat requirements is of fundamental importance for successful protection and conservation of amphibians. However, most field research is focused on ponds or other small wetlands while lakes have been largely overlooked. This is particularly true of our study region, the Boreal/Great Lakes-St. Lawrence forests. The purpose of our study was to examine a sample of small lakes in Northwestern Ontario to determine amphibian species richness and incidence in order to assess their importance as amphibian habitat. Three major differences between lakes and smaller water bodies are size, hydroperiod, and the presence of predators (particularly fish). The species-area effect predicts that a larger area can support more species. Likewise, sites with longer hydroperiod should support more species. Therefore, we might expect a relatively high species richness value in these lakes. However, the presence of predatory fish in large permanent water bodies is likely to have a negative effect on species richness, countering any area benefit. We repeatedly surveyed 31 lakes within a 150km radius of Thunder Bay, Ontario from May-August in 2001 and 2002. We identified species by call or visually and surveys included both day and night visits. We observed 9 of 12 potential species. The most common species were Pseudacris crucifer (100% incidence) and Bufo americanus (90% incidence). Rana pipiens (6% incidence) and Pseudacris triseriata (3% incidence) were the least common species. The average species richness for 2001 and 2002 combined was 4.29 � 0.18. Species richness did not differ between years (t = -0.171, p = 0.87). 51.6% of lakes had the same number of species in 2001 and 2002, 22.6% lost at least one species from 2001 to 2002, while 25.8% of lakes gained at least one species. Similarly, species richness did not differ between lakes where we observed predatory fish (n = 21) and lakes where we did not observe predatory fish (n = 10). This is likely due in part to the nature and availability of refuge habitats on the lakes. We conclude that lakes offer very suitable habitat for most amphibian species in Northwestern Ontario, even 'temporary pond species', due to their variety of habitats. Therefore lakes should not be overlooked as amphibian habitat and for amphibian conservation. This may be especially important considering continuing drought in boreal forest regions.

Infectious diseases have undoubtedly always played major roles in the ecology and evolution of life on earth. Host and pathogen relationships are hypothesized mechanisms for maintaining sexual reproduction, determining host population dynamics, initiating speciation in some systems and even influencing the structure of entire ecosystems. However, the need to understand host-pathogen relationships well enough to manage them has taken on new urgency as emerging infectious diseases have surfaced as major threats to human and wildlife populations alike. Increased awareness and surveillance may account for the apparent "emergence" of some diseases, but in other cases, disease dynamics have fundamentally changed, resulting in an emerging infectious disease. Mechanisms underlying these changes in disease dynamics include habitat alteration, translocation of pathogens and hosts, altered species assemblages and community structure, and climate change. The diversity of these mechanisms makes understanding changes in host-pathogen relationships a complicated affair; it is further complicated by synergistic interactions among mechanisms and a paucity of tractable model systems to study them in.

Pathogens that affect amphibians are taxonomically diverse, with remarkably variable effects on their host populations. For this reason, amphibian pathogens make an unfortunate, yet revealing, set of case studies of mechanisms that alter disease dynamics. In my presentation, I will briefly discuss some of the major pathogens that have received attention from the scientific community including Aeromonas hydrophila, Saprolegnia, chytrid fungi, trematodes and ranaviruses. Using ranaviruses as a model system, I will

discuss some of the mechanisms that mediate disease dynamics and highlight how attention to infectious diseases is crucial on the part of conservation biologists and wildlife managers as well as policy makers and public educators. Indeed, these different groups must work together to address emerging infectious diseases in wildlife and ourselves.

I report on two situations in which neighbours drew my attention to late November concentrations of frogs in excavations on their land, and compare these sites to survival and mortality in small holes I have dug as hibernacula. In 1993 a chlorinated swimming pool contained 92 Rana pipiens, of which 72 were dead and 20 alive. This was said to be an unexceptional number for this site: "Every spring there were always hundreds of frog remains in the deep end of the pool usually quite decayed..." In 2001, 331 frogs were taken from 30cm of water in a newly-dug temporary 4x1x1.5m septic tank ditch, totalling 276 R. pipiens (83%), 43 R. clamitans (13%), and 12 R. septentrionalis (4%); 33 were dead (10%). This was likely most of the frogs in the ditch - the remainder were presumablely killed when the ditch was filled in later in the fall. From 1997-2002 I sampled a total of 418 hibernating frogs in 2 60cm-deep holes in a shallow ditch in a Pine plantation (338 R. pipiens [81%], 71 R. clamitans [17%], 6 R. septentrionalis [1%], and 2 R. catesbeiana [0.5%]). Assessing survival has been difficult, but in only one winter did all the frogs die, while in another those in one hole died and those in the other survived. Conservation implications: The chlorinated in-ground pool routinely killed hundreds of frogs. It was surrounded by a legally-required chain link fence, and a finer mesh on the lower half-metre of this fence would have excluded the Rana. There was something like 1 frog/litre in the septic tank ditch (and doubtful if there would have been more or fewer if leaving the ditch had been easier). Leopard Frogs are abundant here, but secure well-oxygenated hibernacula are rare. The surface and melt-water in small holes and ditches is always well-oxygenated, unlike creek and wetland water that is often anoxic. It is evidently worthwhile for Leopard Frogs to attempt to hibernate in such sites, and in my small holes survival has been something like 75%. I suggest that providing numerous metre-scale excavations as hibernacula might contribute to metapopulation connections across disturbed landscapes - especially if the excavations were sited to reduce the frequency or road crossings. I have, accordingly, enlarged some of the hibernation sites I study to 1-metre dimensions, in order to see how much this increases occupancy and survival.

The five-lined skink is an important species in terms of Canada's natural heritage because it is eastern Canada's only lizard species. It is designated as a species of 'Special Concern' by COSEWIC because of its fragmented range and evidence of historical decline. The largest documented population occurs in Point Pelee National Park. This population is of concern because of its highly isolated nature and evidence of high level of anthropogenic disturbance (habitat degradation, collecting). We have studied the population ecology of skinks at Point Pelee since 1990. We conducted visual surveys of two 'skink hotspots' coinciding with the annual peaks of skink activity (breeding, nesting) to examine population trends and study microhabitat availability. In our earlier work, we determined that skinks show a preference for large moderately-decayed woody debris as refuges. Our surveys revealed that skink abundance declined precipitously from 1990 to 1996 coinciding with high levels of human disturbance to woody debris and evidence of illegal collection. In 1996, habitat restoration by adding suitable woody debris, and increased enforcement began. By 1997, the decline stopped and we observed an increasing trend in skink abundance. Restoration efforts have continued resulting in an even greater volume of woody debris relative to the early 1990's and record high skink abundance in 2001 and 2002. High disturbance levels and natural degradation of woody debris continues, thus requiring constant monitoring of the skink population and the availability of suitable woody debris. Detecting the decline, elucidating its causes, and determining the efficacy of restoration efforts in this population would not have been possible without long-term monitoring. Our studies indicate that microhabitat restoration for recovery of lizard populations can be successful and demonstrate that active management is necessary to promote population persistence in highly stressed and isolated areas.