Ontario is home to eight turtle species, seven of which are classified as endangered or on the verge of being endangered.
In response to the declining turtle population, Carleton associate professor of biology Christina Davy and her team are researching factors impacting these turtles’ livelihoods, including the effects of seismic vibrations, parasites and predators.
The Charlatan sat down with Davy to discuss the ways in which her team tackles these issues, as well as her goals for the future of turtles in Ontario.
The Charlatan (TC): Can you provide a brief overview of your research and process so far?
Christina Davy (CD): In my lab, we try to come up with study designs that will answer an interesting question in ecology or behaviour, and will provide tools to policymakers to do more effective recovery of endangered populations.
We study the effects of different incubation temperatures on developing turtle eggs, how turtles choose nest sites and how the temperatures that the eggs experience might affect hatchling fitness. Our research also provides information for wildlife rehabilitation centres or zoos, so they can make evidence-based decisions about which temperatures will give us hatchlings that have the best success once we release them.
TC: DNA barcoding refers to the process of identifying a species using a short sample of DNA from its blood. Your team has been using DNA barcoding to test for parasites in the turtles. Can you explain that process?
CD: Every time we catch a turtle, we take a sterile insulin syringe to take a blood sample from the tail of the turtle, and we store it for later analysis. That blood sample contains the DNA of the turtle and the DNA of any parasites that are floating in the blood.
Within that DNA sample, we can test and see what’s in there. By looking at that piece of the DNA and lining it up with what we know the DNA sequence is for other species that have already been barcoded, we can assign parasites that we find in the turtles’ blood to their species, or at least to the group of parasites they belong to.
TC: Your team has used incubators to give turtles a leg up on the food chain. How do you avoid disrupting the turtles’ predators through this process?
CD: We boost the turtles past the first big predation risk, which is predation of the nest, and then we release the hatchlings back into the wild at their original nest sites.
There are a few consequences. The sexes of the turtles are determined by temperature, so if we use the wrong temperatures during incubation, we risk skewing the sex ratio of the next generation.
As for predators, the reason nest predation is problematic is because they’re supplemented by humans. Raccoons are very common at these sites because they’re able to get extra food from cottages in the area.
TC: How has government policy affected the dangers facing the turtle population??
CD: The Ontario government released new policies about how to define provincially significant wetlands. They changed the definitions for the category of wetland, making it easier to develop in those areas. Those kinds of policy changes are really bad for all species that rely on wetlands.
TC: Is the implementation of protective policies for turtles a provincial or federal issue?
CD: It’s both, and it’s municipal and individual. None of those scales on their own is enough to move the dial, but altogether, we absolutely can make the changes that we need.
The federal government uses the Species at Risk Act to protect species at risk. In Ontario, we have a provincial Endangered Species Act that protects species on provincial lands and within municipalities. The decisions that city planners make makes a huge difference to how quickly we lose wetlands or where wetlands are restored.
TC: How can university students get involved in this process of protecting turtles and their eggs?
CD: The biggest threat to turtles in Ontario is road mortality. It’s not feasible for students to address habitat loss on their own, but what you say to your elected representatives matters. You can write to your MPP or MP and let them know you care about wetland protection.
If you can safely move a turtle, the trick is to move it in the direction that it’s going and leave it on the other side of the road.
This interview has been edited for length and clarity.
Featured graphic by Alisha Velji.
