Researchers Develop Protective Nests for At-Risk Turtles in Ontario

With all eight native freshwater turtle species of Ontario considered at-risk, researchers have created protective nests to help boost offspring survival.

Researchers at the University of Waterloo and McMaster University designed a nest with materials like moss and lichen to mimic the turtles’ natural rocky nesting sites. As the research team pointed out in their study, published in the journal Restoration Ecology, previous nest restoration efforts often focused on building nests from materials like sand and gravel. 

^{Examples of nest sites created with moss (A), mixed materials (B) and lichen (C). Restoration Ecology}

The team instead focused on designing a nest that would work best for rocky landscapes, where freshwater turtles often create their nests in the cracks of rocks. Plus, they pointed out in their study that the mound nests made with sand and gravel tend to require regular upkeep to prevent plants from growing too densely into the nesting areas.

The researchers created the first nest for a research site at Georgian Bay in 2019 and monitored it for five years. During this time, the researchers didn’t need to make any repairs or adjustments to the nest they created, meaning it could be a low-maintenance way to help with freshwater turtle protection efforts.

^{A Blanding’s turtle at its new nesting site. Hope Freeman / McMaster University}

While freshwater turtles can make their own nests, these efforts are often set back as the animals face threats from habitat destruction.

“The number 1 threat to freshwater turtles in Ontario is habitat loss and degradation from urbanization,” Chantel Markle, the lead author of the study and professor in the Faculty of Environment at the University of Waterloo, said in a press release. “Georgian Bay is one of the last remaining strongholds for some at-risk turtles in Ontario, so this new design is a step towards the survival of the species.”

Additionally, freshwater turtle eggs depend on certain temperatures to produce male or female hatchlings, and too many males or females can limit the reproduction of offspring in future generations, further threatening the survival of at-risk species. So the researchers took extra care to create warm, well-draining nests that would give the offspring the best odds of survival as well as hopefully improving population size in the long-term.

“Taking an interdisciplinary approach to assessing the success of habitat created for animal reproduction is critical,” Markle said. “In this study we evaluated the physical, ecohydrological and ecological success of the created nesting habitat — a combination not often seen in a single study.”

The team found that the eggs were 41% likely to hatch in the human-crafted nests, while the natural nesting sites only had a 10% chance for eggs to hatch.

Next, the researchers plan to scale the nest design to apply to other local, rocky landscapes. Additionally, they made their nest creation process available in the published study to aid turtle conservationists in other areas throughout Canada and the U.S.

^{A female painted turtle after nesting. Chantel Markle / University of Waterloo}