Lake Erie Wetlands Wildlife

The species

Some of Canada’s most species-rich — and most threatened — remaining wetlands are found along Lake Erie’s north shore. Although some of this habitat is protected, human presence and nearby development are placing great strains on the natural ecosystem. Species at risk in these habitats include Blanding’s turtle, northern map turtle, spiny softshell turtle, spotted turtle, snapping turtle (pictured above), eastern foxsnake and Fowler’s toad.  

The project

Wildlife Preservation Canada first became involved in this region in 2004, when we supported research into the nesting success of at-risk turtles at two sites on Lake Erie. This study revealed that virtually 100 per cent of the eggs at these sites were being destroyed before they could hatch. The culprit? Natural predators such as raccoons and skunks, whose populations have exploded in recent decades thanks to food and shelter they find at campsites and cottages.

In response, researcher Ryan Bolton evaluated a variety of methods to protect turtle nests, including caging individual nests, relocating them to large predator-proof enclosures and artificially incubating them in a lab setting.

When Ryan’s project ended in 2008, we began supporting research and recovery efforts led by former Canada’s New Noah Dr. Christina Davy. To protect turtle nests from over-predation, Christina and her team use artificial incubation, which ensures the highest possible rate of hatchling production.

To measure the success of these efforts, they are permanently marking all hatchlings before releasing them back into the wild, and they continue to monitor the populations through trapping and nesting surveys. This is a long-term endeavour, as some turtle species take up to twenty years to reach sexual maturity.

In addition to the ongoing turtle nest protection program, Christina has examined turtle conservation genetics, creating insights that will help us better manage and recover these species.

Since 2013, the project team has also been tracking eastern foxsnakes using radio telemetry to learn more about how they use habitat and select hibernation sites within a human-modified environment. The team is also investigating the distribution of snake fungal disease, an emerging threat to snake populations in north-eastern North America. In 2015 Christina began identifying critical breeding habitat for the Fowler’s toad and assessing the impacts of erosion and invasive phragmites reeds in these sensitive areas.

Results

As of fall 2015, our intervention has resulted in 8,794 Blanding’s, spiny softshell, northern map, and snapping turtle hatchlings being saved and released into Lake Erie, while scientists working in the program have added to the overall body of conservation knowledge by routinely publishing research papers.

Ryan Bolton’s study showed that each nest protection method he tested has its strengths and weaknesses, but all have a positive impact. While artificial incubation is the most costly method, it ensures the highest possible survival rate.

Meanwhile, Christina has developed new genetic markers for snapping and softshell turtles, which have helped define the population structure and important management units for these species in Ontario.

Impact

Our nest protection effort addresses the single biggest threat to turtles along the shores of Lake Erie: nest predation. By ensuring that new generations of turtles hatch, we’re helping secure a future for these species.

Although it will be many years before our rescued hatchlings reach breeding age, population monitoring has already shown that they can survive in the wild. Our survey efforts have also increased surveillance in the area, protecting the spotted turtle population from one of its greatest risks: poaching for the pet trade.

At the same time, Christina’s molecular markers now allow law enforcement to identify the origin of illegally poached and traded turtles, contributing to efforts to combat these illegal activities. Her insights into the landscape-scale genetic structure of several turtle species have helped to prioritize areas for applied conservation approaches that increase connectivity, such as wildlife corridors and translocations.

For more details on this project, check out our field blog.

Support Lake Erie wetlands wildlife! Contribute to Wildlife Preservation Canada today.

Want to do more? Find out how you can help reptiles and amphibians at risk.

Research

Catrysse, J., E. Slavik, A. Leifso, J. Choquette and C.M. Davy. 2015. Mass mortality of mature female Northern Map Turtles (Graptemys geographica). Canadian Field Naturalist 129(1): 80-83.

Oddie, M., S.C. Coombes & C.M. Davy. 2015. Investigation of cues used by predators to detect snapping turtle (Chelydra serpentina) nests. Canadian Journal of Zoology 93(4): 299-304.

Davy, C.M., J.E. Paterson & A.E. Leifso. 2014. When righting is wrong: performance measures require rank repeatability for estimates of individual fitness. Animal Behaviour, 93C: 15-23. https://dx.doi.org/10.1016/j.anbehav.2014.04.013

Davy, C.M. & R.W. Murphy. 2014. Conservation genetics of the endangered spotted turtle (Clemmys guttata) illustrates the risks of “bottleneck tests”. Canadian Journal of Zoology, 92(2): 149–162.

Davy, C.M. 2013. Conservation genetics of Ontario freshwater turtles. (Ph.D. Thesis) Toronto: University of Toronto, 163 pp.

Davy, C.M., P.H. Bernardo & R.W. Murphy. 2013. A Bayesian approach to conservation genetics of Blanding’s turtle (Emys blandingii) in Ontario, Canada. Conservation Genetics. DOI: 10.1007/s10592-013-0540-5.

Davy, C.M., D.M.R. Storisteanu, I.M. Conflitti & R.W. Murphy. 2012. Isolation and characterization of eleven novel polymorphic microsatellite loci in the spiny softshell turtle (Apalone spinifera). Conservation Genetics Resources. DOI: 10.1007/s12686-012-9638-1.

Davy, C.M., A.E. Leifso, I.M. Conflitti & R.W. Murphy. 2012. Characterization of 10 novel microsatellite loci and cross-amplification of two loci in the snapping turtle (Chelydra serpentina). Conservation Genetics Resources. DOI: 10.1007/s12686-012-9624-7.

Bolton, R.M. 2007. Effects of anthropogenic disturbance, nest-site selection, and Dipteran infestation on spiny softshells (Apalone spinifera). (M.Sc. Thesis) Guelph: University of Guelph, 103 pp.