Turtles watch potential mates to scope out their competition, according to recent research by Carleton biology instructor Grégory Bulté.
Bulté and graduate biology student Brooke Huneault made 3D models of turtles and found that the reptiles tried to court the dolls as if they were real. Bulté then set up cameras to collect information on the turtles’ mating habits.
Huneault said she analyzed over 100 hours of footage capturing turtle behaviour and collected statistics on if, when and how long turtles would try to mate with the dolls.
Turtles would sometimes group together, Bulté noticed. He said male and female turtles watched each other to see which other turtles were being selected or paired together. With that information, they make a choice.
“More and more animal behaviourists are realizing that animals will pay attention to what other individuals are doing and make decisions about that,” Bulté said.
Bulté said he predicted that the single female turtles would be more attracted to the single male turtles. The research team also thought that competition for mates would affect how both male and female turtles interact.
The researchers found male turtles were often more likely to interact with female turtles that were unaffiliated with other males.
“We think they’re more taking social information from each other and kind of clueing in on what the other males in the area think of the female,” Huneault said.
Yet, there were outliers. Several times, Bulté said he noted some female turtles who were affiliated with males attracted even more male turtles.
“We think that maybe males are also maybe interested in each other in some ways,” Bulté said. “Maybe they come see other males and want to come and check out what’s going on but then are less likely to interact with the female.”
Using 3D turtle models to collect data is less tedious than attempting to observe turtle habits in the wild, Bulté said.
“It was always pretty difficult to collect data on what they’re actually doing because, you know, all that happens underwater because you could scuba dive, and you know, spook them,” he said.
Huneault said she enjoyed watching funny moments of turtles interacting with their environment, but research into the mating habits of turtles has real applications.
David Seburn is a freshwater turtle specialist at the Canadian Wildlife Federation (CWF). As an amphibian reptile biologist, Seburn has worked in turtle conservation for about 20 years. In the Ottawa River, seven Canadian turtle species are categorized as at risk by the Ottawa Riverkeeper.
Seburn said part of maintaining a stable turtle population focuses on increasing their reproductive success. Understanding turtles’ mating habits improves the group’s ability to facilitate repopulation.
Seburn said that the CWF has released just over 2,000 hatchlings to date in Ottawa. However, he said protecting turtles already living in the wild is much more important for conservation.
“You’re basically wasting your time mating and laying eggs when those eggs just get eaten by racoons,” Seburn said.
Bulté, however, said his interest in turtles was not born from an interest in conservation.
“[My interest] is simple,” Bulté said. “Turtles have more complex behavioural patterns than they are commonly credited for.”
Huneault said their models and decoy methods can be replicated and used for other research projects on animal behaviour in a natural setting in the future.
CORRECTION: A previous version of this article stated eight Canadian turtle species in the Ottawa River were categorized as at risk under Canada’s Species at Risk Act. In fact, seven Canadian turtle species in the Ottawa River are categorized as at risk by the Ottawa Riverkeeper. The article was last updated on Nov. 22.
Featured image provided by Grégory Bulté.
