Past Annual Meetings:
7th Annual Meeting, Winnipeg, Manitoba September 27-30, 2002
Presentation Abstracts |
Poster Abstracts | Photos |
Award Recipients| Organizing Committee
Presentation Abstract Index: The following are the abstracts from the 7th
annual meeting. Abstracts are organized in alphabetical order by first author's last name.
Abstracts of the presentations are available in print form through CARCNET. Please
contact us.
- AMPHIBIAN DISTRIBUTION IN NORTHWESTERN ONTARIO: ASSESSING THE ROLE OF LOCAL HABITAT AND
LANDSCAPE CHARACTERISTICS - Abbott
- COMPARATIVE PHYLOGEOGRAPHY OF TWO NORTH AMERICAN FROGS: CRYPTIC LINEAGES, CONTACT ZONES AND
CONSERVATION PRIORITIES - Austin
- EUROPEAN WALL LIZARDS (PODARCIS MURALIS) IN VICTORIA, BC -
Bertram
- ACTIONS OF THE HERPETOFAUNA CONSERVATION ACTION GROUP IN THE SOUTH OKANAGAN -
Bishop
- TESTING ACCURACY AND PRECISION OF SKELETOCHRONOLOGY IN KNOWN-AGE BULLFROGS
(RANA CATESBEIANA) FROM A NORTHERN POPULATION - Brooks
- AN ANALYSIS OF POPULATION VIABILITY OF THE WOOD TURTLE (CLEMMYS INSCULPTA) IN
SOUTHERN ONTARIO - Brooks
- TURTLE SPECIES LOSS AND SHIFTING POPULATION STRUCTURE AT POINT PELEE NATIONAL PARK: THE
EFFECT OF PREDATORS? - Browne
- THE AMPHIBIAN SPERM INHIBITION TOXICOLOGICAL TEST (ASITT) METHOD -
Christensen
- CONSERVATION ACTIONS TO REDUCE MORTALITY OF SNAKES ON ROADS AT CFB SUFFIELD AND SUFFIELD
NATIONAL WILDLIFE AREA, ALBERTA - Didiuk
- AMPHIBIAN AND REPTILE SPECIES AT RISK IN CANADA: THE ARRIVAL OF SARA -
Green (Invited Speaker)
- FOWLER'S TOADS: AN UPDATE - DISPERSAL AND VIABILITY OF FOWLER'S TOADS
(BUFO FOWLERI) POPULATIONS IN CANADA - Green
- LANDSCAPES WITH REPTILES: SNAKES AND ROCKS IN AN URBAN MATRIX -
Gregory
- ACTIVITIES OF THE OREGON SPOTTED FROG RECOVERY TEAM -
Haycock
- REGIONAL STABILITY OF SPECIES RICHNESS AND INCIDENCE IN A HIGHLY DYNAMIC AMPHIBIAN FAUNA -
Hecnar
- CONSERVATION OF FIVE-LINED SKINKS IN ONTARIO: GENETIC AND ECOLOGICAL PERSPECTIVES -
Howes
- THE NATURAL HISTORY OF THE GRASS SNAKE (NATRIX NATRIX) AT A SITE IN SOUTHERN ENGLAND
- Isaac
- NORTHERN LEOPARD FROG REINTRODUCTION PROJECT - Kendell
- COMPARISON OF INDUCED EFFECT OF ORGANOPHOSPHATE (MALATHION) AND A PYRETHROID (CYPERMETHRIN)
ON CHOLINESTERASE ACTIVITY IN LIVER, KIDNEY AND BRAIN OF THE INDIAN GARDEN LIZARD CALOTES
VERSICOLOR DAUDIN - Khan
- SEARCHING FOR THE JEFFERSON SALAMANDER: HOW TO FIND AND IDENTIFY AMBYSTOMA JEFFERSONIANUM
- Lynn
- THE GARDEN OF EDEN REVISITED: SNAKES, SEX AND SCENTS IN MANITOBA! -
Mason (Invited Speaker)
- THE DESIGN OF AN ARTIFICIAL SNAKE DEN: RED-SIDED GARTER SNAKES IN THE INTERLAKE REGION OF
MANITOBA, CANADA - Nuttall
- EFFECTS OF ETHYNYLESTRADIOL ON EARLY DEVELOPMENT OF AMPHIBIANS IN A BOREAL LAKE -
Park
- SOME TECHNIQUES AND RESULTS FOR HABITAT RESTORATION FOR REPTILES AND AMPHIBIANS AT PELEE
ISLAND, ONTARIO - Porchuck
- BLUE RACER ROAD MORTALITY IN SOUTHWESTERN ONTARIO - Porchuck
- GOING SOUTH TO EXPAND THE CARCNET: PELEE ISLAND, ONTARIO, 2003 -
Porchuck
- IDENTIFYING CRITICAL HABITAT: GUIDANCE FROM PHYLOGENETIC, ECOLOGICAL, AND EVOLUTIONARY
PERSPECTIVES - Prior
- FUNDING INITIATIVES IN VIEW OF THE SPECIES AT RISK ACT - Prior
- BEHAVIOURAL RESPONSES OF THE SNAPPING TURTLE (CHELYDRA SERPENTINA SERPENTINA)
AFTER EXPOSURE TO THE ENVIRONMENTAL POLLUTANT 4-OCTYLPHENOL - Raymond
- THE NARCISSE SNAKE TUNNEL PROJECT: CONSERVATION THROUGH CO-OPERATION -
Roberts
- EXAMINING NORTHWESTERN ONTARIO LAKES IN TERMS OF AMPHIBIAN SPECIES RICHNESS AND HABITAT
SUITABILITY - Robinson
- INFECTIOUS DISEASES AND AMPHIBIANS -
Schock (Keynote Speaker)
- AUTUMNAL MORTALITY AND SURVIVAL OF RANA IN SMALL ANTHROPOGENIC AQUATIC HIBERNACULA IN
GRENVILLE COUNTY, ONTARIO - PITFALL TRAPS OR PREFERRED SITES? - Schueler
Poster Presentation Index:
- POPULATION TRENDS AND CONSERVATION OF THE FIVE-LINED SKINK (EUMECES FASCIATUS) AT
POINT PELEE NATIONAL PARK, ONTARIO. - Hecnar
- INFLUENCE OF ESTROGENIC CONTAMINANTS ON AMPHIBIAN SEX DIFFERENTIATION -
MacKenzie
- FISH WINTERKILLS SHAPE AMPHIBIAN RECRUITMENT IN WESTERN BOREAL LAKES -
Paszkowski
- PATTERNS OF AGE, SIZE AND GROWTH IN CANADIAN TOAD POPULATIONS BASED ON SKELETOCHRONOLOGY -
Paszkowski
- HABITAT USE OF THE NORTHERN PRAIRIE SKINK, EUMECES SEPTENTRIONALIS SEPTENTRIONALIS,
IN SPRUCE WOODS PROVINCIAL PARK, MANITOBA - Scott
Presentation Abstracts:
AMPHIBIAN DISTRIBUTION IN NORTHWESTERN ONTARIO:
ASSESSING THE ROLE OF LOCAL HABITAT AND LANDSCAPE CHARACTERISTICS
Virginia A. Abbott, Shannon Maronese and Stephen J. Hecnar
Department of Biology, Lakehead University, 955 Oliver Rd., Thunder Bay, ON P7B 5E1
Telephone: 807-343-8670, Fax: 807-346-7796, Email: [email protected]
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.
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COMPARATIVE PHYLOGEOGRAPHY OF TWO NORTH AMERICAN
FROGS: CRYPTIC LINEAGES, CONTACT ZONES AND CONSERVATION PRIORITIES
James D. Austin, Peter T. Boag and Stephen C. Lougheed
Department of Biology, Queen's University, Kingston, ON Canada K7L 3N6
Telephone: 613-533-6128, Fax: 613-533-6617, Email: [email protected]
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."
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EUROPEAN WALL LIZARDS (PODARCIS MURALIS) IN
VICTORIA, BC.
Nadine Bertram
Department of Biology, University of Victoria, PO Box 3020, Victoria, BC. V8W 3N5
Telephone: 250-721-7103, Fax: 250-721-7120, Email: [email protected]
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.
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ACTIONS OF THE HERPETOFAUNA CONSERVATION ACTION GROUP IN
THE SOUTH OKANAGAN.
Christine A. Bishop1, Mike Sarell2, Orville
Dyer3 and Laura Friis4
1Canadian Wildlife Service, 5421 Robertson Road, Delta BC. V4K 3N2;
2Ophiucus Consulting; 3BC Ministry of Water Air Land Protection;
4Wildlife Branch, BC Ministry of Environment, Lands and Parks
Telephone: 604-940-4671, Fax: 604-946-7022, Email: [email protected]
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.
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TESTING ACCURACY AND PRECISION OF SKELETOCHRONOLOGY IN
KNOWN-AGE BULLFROGS (RANA CATESBEIANA) FROM A NORTHERN POPULATION
Ronald J. Brooks, Sara L. Ashpole, Matt Rudisi and
Kevin A. Judge
Department of Zoology, University of Guelph, Guelph, ON. N1G 2W1
Telephone: 519-824-4120 X 3944, Fax: 519-824-1656, Email: [email protected]
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.
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AN ANALYSIS OF POPULATION VIABILITY OF THE WOOD
TURTLE (CLEMMYS INSCULPTA) IN SOUTHERN ONTARIO
Ronald J. Brooks and Melissa A. Cameron
Department of Zoology, University of Guelph, Guelph, ON. N1G 2W1
Telephone: 519-824-4120 X 3944, Fax: 519-824-1656, Email: [email protected]
Population data on the southern Ontario population of wood turtles (Glyptemys
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.
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TURTLE SPECIES LOSS AND SHIFTING POPULATION STRUCTURE AT
POINT PELEE NATIONAL PARK: THE EFFECT OF PREDATORS?
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.
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THE AMPHIBIAN SPERM INHIBITION TOXICOLOGICAL
TEST (ASITT) METHOD
Jennie A. Christensen, Christine A. Bishop, John S. Richardson and
John Elliott
Department of Forest Sciences, University of British Columbia, Vancouver, BC. V6T 1Z4
Telephone: 604-612-1476, Fax: 604-822-9102, Email: [email protected]
The Amphibian Sperm Inhibition Toxicological Test (ASITT) method is fast, simple,
cost-effective, and has the potential to contribute valuable information to a growing database
of toxicological endpoints used to evaluate health risks. It will also decrease the number and
suffering of amphibians as test organisms. ASITT measures the effects of environmental
contaminants on various sperm kinematics (curvilinear velocity–VCL, straight line
velocity–VSL, average path velocity–VAP, linearity–LIN, straightness–STR,
wobble–WOB) and sperm motility phases (non-motile, idle, progressive, hyperactivated). The
effects of pH, osmolality and zinc on Xenopus laevis sperm motility are discussed here. pH
7.0 displayed the highest percent motility of the entire range of pH's tested (5.5 to 7.8).
Sperm solutions (SS) were diluted with distilled water (DW) in various SS:DW ratios (1:1, 1:2,
1:3, 1:4, 1:5) to observe the effects of osmolality on sperm motility. There was a significant
quadratic dose response with percent total motile and percent progressives. The SS:DW 1:3 had
the highest percent motility and highest velocities. The results from the pH and osmolality test
series were used to develop a control solution for subsequent testing with zinc. Seven
concentrations of zinc were used in this research (0 to 1417 µg/L). Zinc is prevalent in
water downstream of acid mine drainage, and has been found at concentrations >10,000
µg/L. Increasing zinc caused a significant decrease in percent motility in a linear dose
response, where motility reached 64% of controls at 1417 µg/L. Percent progressives also
decreased in a significant linear dose response. Previous research has shown that a decrease in
sperm motility negatively affects fertilization success in amphibians. As indicated by the
present research, Xenopus laevis sperm motility is very sensitive to the aquatic
environment and could act as a more sensitive water quality indicator than other indices. For
instance, Xenopus laevis tadpoles show serious malformations to zinc at concentrations
>2700 µg/L, compared to our results showing sperm inhibition at concentrations as low
as 334 µg/L. This test is in very preliminary stages and more work in this area may lend
weight to ASITT's effectiveness and usefulness as a standardized laboratory method for toxicity testing.
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CONSERVATION ACTIONS TO REDUCE MORTALITY OF SNAKES ON ROADS AT CFB SUFFIELD AND SUFFIELD
NATIONAL WILDLIFE AREA, ALBERTA
Andrew B. Didiuk
Wildlife Biologist, Canadian Wildlife Service, 115 Perimeter Road, Saskatoon SK. S7N OX4
Email: [email protected]
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.
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AMPHIBIAN AND REPTILE SPECIES AT RISK IN CANADA: THE
ARRIVAL OF SARA
David M. Green Redpath Museum, McGill University, 859
Sherbrooke St. W., Montreal, Quebec. H3A 2K6
Telephone: 514-398-4086 Ext 4088, email: [email protected]
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.
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FOWLER'S TOADS: AN UPDATE - DISPERSAL AND VIABILITY OF
FOWLER'S TOADS (BUFO FOWLERI) POPULATIONS IN CANADA
David M. Green and Alex M. Smith
Redpath Museum, McGill University, 859 Sherbrooke St. W., Montreal, Quebec. H3A 2K6
Telephone: 514-398-4086 ext 4088, email: [email protected]
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.
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LANDSCAPES WITH REPTILES: SNAKES AND ROCKS IN AN URBAN
MATRIX
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]
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.
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ACTIVITIES OF THE OREGON SPOTTED FROG RECOVERY TEAM
Russ Haycock
Co-chair, Oregon Spotted Frog Recovery Team and Principal, Hyla Environmental Services Ltd.,
636 Thurston Close Port Moody, BC
Telephone: 604-469-2910, Fax: 604-469-5753, Email: [email protected]
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.
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REGIONAL STABILITY OF SPECIES RICHNESS AND INCIDENCE
IN A HIGHLY DYNAMIC AMPHIBIAN FAUNA
Stephen J. Hecnar and Darlene R. Hecnar
Department of Biology, Lakehead University, 955 Oliver Rd., Thunder Bay, ON. P7B 5E1
Telephone: 807-343-8250, Fax: 807-346-7796, Email: [email protected]
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.
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CONSERVATION OF FIVE-LINED SKINKS IN ONTARIO: GENETIC AND
ECOLOGICAL PERSPECTIVES.
Briar Howes and Stephen C. Lougheed
Dept. of Biology, Queen's University, Kingston, ON. K7L 3N6
Telephone: 613-533-6000 x 75051, Fax: 613-533-6617, Email: [email protected]
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.
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THE NATURAL HISTORY OF THE GRASS SNAKE (NATRIX
NATRIX) AT A SITE IN SOUTHERN ENGLAND.
Leigh Anne Isaac and 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] (LAI), [email protected] (PTG)
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.
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NORTHERN LEOPARD FROG REINTRODUCTION PROJECT
Kris Kendell
Alberta Conservation Association, 7th Floor, O.S. Longman Building, 6909-116 Street,
Edmonton, Alberta. T6H 4P2
Telephone: 780-422-4764, Fax: 780-422-9685, Email: [email protected]
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.
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COMPARISON OF INDUCED EFFECT OF ORGANOPHOSPHATE (MALATHION)
AND A PYRETHROID (CYPERMETHRIN) ON CHOLINESTERASE ACTIVITY IN LIVER, KIDNEY AND BRAIN OF THE
INDIAN GARDEN LIZARD CALOTES VERSICOLOR DAUDIN
Muhammed Zaheer Khan and Farina Fatima
Department of Zoology (Wildlife), University of Karachi, Karachi-75270 Pakistan.
Telephone: 0303 623 2237, Fax: (92-21) 4409 336, Email: [email protected]
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.
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SEARCHING FOR THE JEFFERSON SALAMANDER: HOW TO FIND AND I
DENTIFY AMBYSTOMA JEFFERSONIANUM
Heather A. Lynn and J.P. Bogart
Department of Zoology, University of Guelph, Guelph, ON, N1G 2W1
Phone: 519-824-4120 x6260, Fax: 519-767-1656, email: [email protected]
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. T
his 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.
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THE GARDEN OF EDEN REVISITED: SNAKES, SEX AND SCENTS IN
MANITOBA!
Robert T. Mason
Department of Zoology, Oregon State University, 3029 Cordley Hall, Corvallis, Oregon 97331
Telephone: 541-737-4107, Fax: 541-737-0501, E-Mail: [email protected]
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.
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THE DESIGN OF AN ARTIFICIAL SNAKE DEN: RED-SIDED G
ARTER SNAKES IN THE INTERLAKE REGION OF MANITOBA, CANADA.
Dan Nuttall
Faculty of Architecture, 201 Russell Building, University of Manitoba, Winnipeg, MB. R3T 2N2
Telephone: 204-474-6868, Fax: 204-474-7532, Email: [email protected]
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.
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EFFECTS OF ETHYNYLESTRADIOL ON EARLY DEVELOPMENT OF
AMPHIBIANS IN A BOREAL LAKE.
Brad Park, Karen Kidd and J.G. Eales Freshwater Institute,
501 University Crescent,Winnipeg, Manitoba, R3T 2N6
Telephone: 204-984-5542, Fax: 204-984-2404, Email: [email protected]
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 17ß-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.
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SOME TECHNIQUES AND RESULTS FOR HABITAT RESTORATION
FOR REPTILES AND AMPHIBIANS AT PELEE ISLAND, ONTARIO
Ben Porchuk
The Wilds of Pelee Island Outdoor Centre for Conservation, 167 Curry Dyke Rd., Pelee Island, ON.
N0R 1M0.
Telephone: 519 724-9918, Email: [email protected]
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.
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BLUE RACER ROAD MORTALITY IN SOUTHWESTERN
ONTARIO
Ben Porchuk
The Wilds of Pelee Island Outdoor Centre for Conservation, 167 Curry Dyke Rd., Pelee Island, ON.
N0R 1M0.
Telephone: 519 724-9918, Email: [email protected]
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GOING SOUTH TO EXPAND THE CARCNET: PELEE ISLAND,
ONTARIO, 2003
Ben Porchuk
The Wilds of Pelee Island Outdoor Centre for Conservation, 167 Curry Dyke Rd., Pelee Island, ON.
N0R 1M0
Telephone: 519-724-9918, Email: [email protected]
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 3rd 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.
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IDENTIFYING CRITICAL HABITAT: GUIDANCE FROM PHYLOGENETIC, E
COLOGICAL, AND EVOLUTIONARY PERSPECTIVES
Kent A. Prior
Canadian Wildlife Service, Hull, Quebec K1A 0H3
Telephone: 819-994-2338, Email: [email protected]
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.
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FUNDING INITIATIVES IN VIEW OF THE SPECIES AT RISK ACT
Kent A. Prior and Robert Decarie
Canadian Wildlife Service, Hull, Quebec K1A 0H3
Telephone: 819-994-2338, Email: [email protected]
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BEHAVIOURAL RESPONSES OF THE SNAPPING TURTLE
(CHELYDRA SERPENTINA SERPENTINA) AFTER EXPOSURE TO THE ENVIRONMENTAL POLLUTANT
4-OCTYLPHENOL
Joanne E. Raymond1, Sara L. Ashpole1,
Shane de Solla1, Vance L. Trudeau2 and Ronald J. Brooks1.
1Department of Zoology, University of Guelph, Guelph. Ontario, N1G 2W1
2 Department of Biology and Centre for Advanced Research in Environmental Genomics,
University of Ottawa, Ottawa, Ontario, Canada, K1N 6N5
Telephone: 519-824-4120 X 3944, Fax: 519-767-1656, Email: [email protected]
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 (Nt= 84) from each of the 6 clutches was r
andomly assigned to three treatments. The number of turtles used per treatment type include:
negative control (well-water) N = 24, positive control (17ß–estradiol) 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.
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THE NARCISSE SNAKE TUNNEL PROJECT: CONSERVATION
THROUGH CO-OPERATION
David E. Roberts
Manitoba Conservation, Operations Division, Interlake Region, Box 6000, Gimli, MB. R0C 1B0
Email: [email protected]
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%.
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EXAMINING NORTHWESTERN ONTARIO LAKES IN TERMS OF
AMPHIBIAN SPECIES RICHNESS AND HABITAT SUITABILITY.
Jeff N. Robinson, Felix Eigenbrod, Monique Missonne and
Stephen J. Hecnar
Dept. of Biology, Lakehead University 955 Oliver Road Thunder Bay, ON P7B 5E1
Telephone: 807-343-8670, Email: [email protected]
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.
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INFECTIOUS DISEASES AND AMPHIBIANS
Danna M. Schock
Department of Biology, Arizona State University, Tempe, AZ, USA. 85287-1501
Telephone: 306-966-5815, Fax: 306-966-7439, Email: [email protected]
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.
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AUTUMNAL MORTALITY AND SURVIVAL OF RANA IN
SMALL ANTHROPOGENIC AQUATIC HIBERNACULA IN GRENVILLE COUNTY, ONTARIO - PITFALL TRAPS OR
PREFERRED SITES?
Frederick W. Schueler
Eastern Ontario Biodiversity Museum, P.O. Box 1860, Kemptville, ON. K0G 1J0
Telephone: 613-258-3107, Email: [email protected]
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.
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Poster Abstracts:
POPULATION TRENDS AND CONSERVATION OF THE FIVE-LINED
SKINK (EUMECES FASCIATUS) AT POINT PELEE NATIONAL PARK, ONTARIO
Darlene R. Hecnar and Stephen J.Hecnar
Department of Biology, Lakehead University, 955 Oliver Rd., Thunder Bay, ON. P7B 5E1
Telephone: 807-343-8250, Fax: 807-346-7796, Email: [email protected]
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.
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INFLUENCE OF ESTROGENIC CONTAMINANTS ON AMPHIBIAN
SEX DIFFERENTIATION
Connie A. Mackenzie1, Chris D. Metcalfe1, Michael Berrill1
and Bruce D. Pauli2
1Watershed Ecosystems Program, Trent University, Peterborough, ON and
2Environment Canada, Canadian Wildlife Service, National Wildlife Research Centre,
100 Gamelin Blvd., Hull, PQ. K1A 0H3
Telephone: 819-953-2634, Fax: 819-953-6612, Email: [email protected]
Despite continued concerns over declining world amphibian populations, few studies have
addressed the effects of environmentally relevant contaminants on the sexual differentiation of
anurans. Leopard Frog (Rana pipiens) and Wood Frog (Rana sylvatica) tadpoles were
exposed to aqueous solutions of xenoestrogens during their larval development. Results indicate
that R. pipiens are sensitive to low concentrations of estradiol (1, 10, 50 and
100 µg/L) and ethinylestradiol (1 and 10 µg/L), producing 100% females or
ovo-testes, an intersex condition with both ovarian and testicular tissue present in the gonad.
Exposure of R. pipiens to 10 and 100 µg/L nonylphenol, a degradation product of the
nonylphenol polyethoxylate class of nonionic surfactants, produced a significant increase in the
incidence of ovo-testes at the highest concentration. Similar exposures of R. sylvatica
failed to produce deviations from the expected 50:50 (Male:Female) sex ratio, however, treatment
groups showed a higher incidence of atretic oocytes, as well as ovarian characteristics in the
testes. These results indicate that amphibians are sensitive to low concentrations of endocrine
disrupting chemicals (EDCs) found in aquatic environments. Amphibians may be exposed to EDCs
from agricultural run-off of animal manure containing estrogens, as well as from sewage
treatment plant effluent containing alkylphenols and steroids. These results shed some light on
the potential implications of current water management practices on wildlife health.
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FISH WINTERKILLS SHAPE AMPHIBIAN RECRUITMENT IN
WESTERN BOREAL LAKES
Cynthia Paszkowski, Brian Eaton, William Tonn and Andy Danylchuk
University of Alberta, Dept. of Biological Sciences, Edmonton AB. T6G 2E9
Telephone: 780-492-1286, Fax: 780-492-9234, Email: [email protected]
Interactions with fishes have played key roles in shaping the reproductive strategies,
metapopulation dynamics, and distribution of amphibians. Declines or local extinctions of
amphibian populations have frequently been linked to introductions of non-native fish species.
Most information on interactions between fishes and amphibians has been generated by short-term
laboratory or enclosure studies, or surveys documenting patterns of co-occurrence at the
landscape level. We monitored native fish and amphibian populations at 12 north-central Alberta
lakes (14 - 157 ha) over 5 years. Five lakes were dominated by large-bodied fish species, most
notably piscivorous northern pike (Esox lucius) and yellow perch (Perca flavescens).
Six lakes contained only small-bodied species, chiefly brook stickleback (Culaea
inconstans) and fathead minnow (Pimephales promelas), and one lake was fishless.
Amphibian abundance responded strongly to large changes in populations of both large- and
small-bodied fish. Toads (boreal toad [Bufo boreas] and Canadian toad [B. hemiophrys]) responded to changes in abundance of
large-bodied piscivores, whereas wood frog (Rana sylvatica), reacted more strongly to
changes in populations of small-bodied fish. The most marked responses coincided with declines
in fish densities due to winterkills resulting in dramatic increases in larval amphibian
recruitment to metamorphosis the following summer. Within the boreal-forest landscape, periodic
high recruitment events from lakes may be an important source of dispersing juvenile anurans for
founding new populations or rescuing declining populations associated with smaller, less permanent
waterbodies.
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PATTERNS OF AGE, SIZE AND GROWTH IN CANADIAN TOAD
POPULATIONS BASED ON SKELETOCHRONOLOGY
Cynthia Paszkowskiand Brian Eaton
University of Alberta, Department of Biological Sciences, Edmonton, AB. T6G 2E9|
Telephone: 780-492-1286, Fax: 780-492-9234, Email: [email protected]
Formerly, the Canadian toad (Bufo hemiophrys) was widely distributed across eastern
Alberta with a range stretching 1300 km north to south. Since the 1980s, the species has nearly
disappeared in the grasslands of southern Alberta, but remains relatively common in the northern
forests. Demographic information on Canadian toad populations, needed to develop conservation
strategies for the species, is sparse. We used skeletochronology based on phalangeal bones to
determine size-at-age relationships and longevity, and to compare demographic patterns among
southern and northern populations. We aged 226 Canadian toads that were captured and released
during field studies or were part of museum collections. One unique sample from the Canadian
Museum of Nature consisted of an entire breeding aggregation of 80 animals collected at a single
southern site near Brooks, Alberta in 1962. Populations differed in size-at-age relationships at
both small and large geographic scales. Moreover, individuals of the same size and sex from the
same population varied substantially in age. In general, toads from Brooks tended to be larger
than same-age individuals from boreal sites near Lac la Biche. Canadian toads proved long-lived
with individuals > 7 years old encountered at southern and northern sites. Longevity, coupled
with high fecundity and the persistence of boreal populations despite natural inter-annual
variation in breeding success, suggests that remnant Canadian toad populations in southern
Alberta may have the capacity to recover if appropriate wetlands and adjacent terrestrial
habitats are restored.Top of Page
HABITAT USE OF THE NORTHERN PRAIRIE SKINK, EUMECES
SEPTENTRIONALIS SEPTENTRIONALIS, IN SPRUCE WOODS PROVINCIAL PARK, MANITOBA.
Jacey L. Scott
Natural Resources Institute, University of Manitoba, 303-70 Dysart Road, Winnipeg, MB. R3T 2N2
Phone: 204-474-8152, Fax: 204-261-0038, Email: [email protected]
Although habitat correlations cannot be interpreted as cause-and-effect relationships, they
are valuable to managers because they can help guide management of habitat for a population, a
species or a community. The goal of this study is to determine the nature of habitat use by the
northern prairie skink, Eumeces septentrionalis septentrionalis, in the sandhills region
of southwestern Manitoba. As well, habitat availability and potential limiting factors will be
determined to aid in the development of a management plan for the northern prairie skink in
Manitoba. The sandhills region of southwestern Manitoba is characterized by an undulating
topography of sandy soils supporting boreal coniferous forest, deciduous forest and grassland
vegetation. Generally, northern prairie skinks have been sighted in mixed-grass prairie under
artificial cover. Skinks are frequently found under and are attracted by artificial debris,
however there is little information on how natural habitats are used by skinks. Without this
knowledge it is impossible to predict how future habitat change may affect populations or how to
best manage habitat to ensure population viability. From signs and direct observation, habitat
requirements and distribution of the northern prairie skink are being established. Trials of
coverboards have been undertaken, with microclimatic measures made to determine how individuals
respond to the presence of these sampling tools. Continuation of observations of habitat
requirements and distribution will be completed as well as additional monitoring and tracking
that is deemed necessary in the following year. This poster presents a working project,
highlighting some preliminary findings of the first field season.
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