CSRI students study turtle survival and habitat 

Three Cornell College students are spending their days studying turtle species on a nature preserve near the Mississippi River as part of the Cornell Summer Research Institute (CSRI).

Assistant Professor of Biology Joshua Otten is teaming up with seniors Sarah Renaud, Jason Ramos, and Peyton Bainbridge to study the impact of humans and climate change on turtle behavior and habitat in Iowa. From locating and analyzing nests to tracking their sun-basking behavior, the research team collects a lot of data.  

“The project that we’re working on has been ongoing since 1973 and is one of the longest ongoing wildlife studies in Iowa,” Otten says. “One of the things that we were originally interested in was the yellow mud turtle decline, but we’ve expanded upon that and are looking at some of the anthropogenic disturbances to turtles–understanding how people have shaped their environment and impacted these turtle populations.”

The students are spending long days out in the field with their professor.

“First we start the day by looking for nesting turtles,” explains Ramos, an ecology and evolutionary biology major from Illinois. “We are out looking until lunchtime. After that, either we process nests, which means we count the eggs and measure them, or we track turtles with transmitters. The last thing we do is check our aquatic traps located in the wetlands to document what species occur there.”

Ramos and Renaud are specifically focusing on the nesting habits of turtles they find on the preserve. Ramos says ornate box turtles typically lay four to five eggs, whereas snapping turtles can lay around 40. Rising temperatures could have a big impact on turtle nests because many turtle species have temperature-dependent sex determination. 

“With the issue of rising temperatures, there’s going to be a concern for more females to males ratio. That’s not good for mating seasons and a balanced population when it comes to increasing numbers for these endangered species,” says Renaud, an ecology and evolutionary biology major from Michigan.

Eggs incubated below 28 degrees C (82 degrees F) typically produce males and those above 31 degrees (88 degrees F) typically produce females.

So how do they catch the turtles to study each one?

That’s a big part of Bainbridge’s focus this summer. 

The team has selected about a dozen turtles in which they’ve epoxied radio transmitters onto their shells. Bainbridge, a behavioral neuroscience major from Illinois who is interested in studying animal behavior, is working to understand how and where the turtles are moving.

“We put little transmitters on the turtles and they send off a beacon,” Bainbridge said. “Then, using an antenna and a receiver, I can find out where they’re located based on the strongest beep the receiver gives off,” Bainbridge says. “We, then, hone in on their location and drop a pin in Google Maps, so we can find out where they were located within the preserve. Then, I record their behavior and the environment that they’re in.”

Along with the transmitters, a data logger is also epoxied onto the shell. 

“The data logger has a little solar panel on it that tells us how much light the turtle is experiencing throughout the day,” Otten says. “In addition, it also tells us how warm that turtle is, taking a data point every five minutes. We’re looking at how much time they spend basking in the sun each day, each week, to see if there are differences in the males and the females.”

The team also has traps set in wetlands and fencing with traps on dry land, which are designed to safely capture turtles. The students say they’re enjoying spending time on a nature preserve and getting hands-on experiences with research, data collection, and exploring Iowa. 

“It’s amazing being able to walk around on this beautiful preserve and stumble across amazing species every day,” Bainbridge said. “We can come across 20 turtles in a day here just walking around. It’s a place unlike anywhere else that I’ve ever experienced.”

Plus, they’re gaining valuable experience for their future careers as they work closely with their professor and learn skills that will support their resumes and job or graduate school applications.

“Following CSRI, these students all have research experience that will help them when applying for an internship or another summer research job,” Otten said. “Then once they graduate, they’ve developed a lot of additional skills to land a great job or get into grad school. So I think what Cornell does with CSRI is very valuable for the students.”

The Cornell Summer Research Institute runs each summer for eight weeks. Students work directly with their professors on one of many projects across several disciplines throughout the summer.