Parasites in cardinals studied by SUNY Oswego honors student

OSWEGO, N.Y. — Urbanization, parasites and cardinals all come together in one Oswego student’s honors thesis.

Sonia Hernandez, a senior majoring in zoology, is in the final semester of her research project. After spending time working on fieldwork and microscopy throughout the summer and previous years, her project is nearing its completion.

“I am basically detecting avian malaria in rural and urban Northern cardinals, and how their parasite load affects their plumage coloration and body condition,” Hernandez said. Hernandez uses she/they pronouns.

Hernandez is working on this project as her honors thesis, the final project that all SUNY Oswego honors students are required to complete. The projects typically take place across several semesters and involve faculty advisors to assist with the process. Her faculty advisors are Daniel Baldassarre, Andrew McElwain and Daniel Sard.

Hernandez worked with her advisors to capture cardinals in two different locations, Rice Creek Field Station in Oswego and Barry Park in Syracuse. After capturing them, they took blood samples and made blood smears, Hernandez said. They also took morphological data, such as images of feathers, samples of feathers, fecal samples, and body measurements.

“We’re basically trying to see if there are more parasites present in the rural or urban [populations],” they said. She later added, “we’re trying to see how urbanization is affecting these parasites.”

Baldassarre is an assistant professor and provost teaching fellow at SUNY Oswego and is one of Hernandez’s advisors, focusing especially on Northern cardinals. He described how Hernandez reached out to him with interest in the field of wildlife disease and how they captured cardinals to study over the summer.

“I realized there was a very interesting intersection between the stuff she was interested in and the stuff I was interested in, which is basically this idea that the diseases that animals can get can affect their body and their ability to do things like signal to other members of their species,” Baldassarre said.

Baldassarre (left) and Hernandez (right) work together to capture cardinals to study. Photo courtesy of Sonia Hernandez

There are three different types of parasites that Hernandez might find when examining birds. These parasites can be fatal to young birds and cause adverse symptoms in others.

“I find it really interesting to work with diseases and parasites, just because I really want to be able to one day work in zoonotic diseases and see how people are affecting the transmission rates with animals,” Hernandez said. “A lot of the time, fragmentation is basically pushing people closer to these animals, and so it increases the likelihood of diseases being crossed between both hosts.” Hernandez noted that the strain of avian malaria that she studies is not transmissible to humans.

She also described the story of native Hawaiian forest birds who were infected, causing 10 species to become extinct. “Though we haven’t seen our birds here be extinct by the parasite, it’s not to say it’s not possible,” Hernandez said.

“This project is honestly very labor-intensive,” they said. Currently, Hernandez is working on “taking [their] slides and taking 15 images and fields of view.” They added that all of this is done manually and each cell must be counted individually. She said she typically spends time in the lab taking pictures and working with slides and outside of the lab reading literature.

Hernandez takes pictures of the slides she creates from blood samples, such as this one, where the arrows point to white blood cells and the circles show luecocytozoons (a type of parasite). Photo courtesy of Sonia Hernandez

Baldassarre said that they are looking for correlation between the lab measurements and parasitic infection in the birds.

“There’s a lot of interesting data to look at; it’s going to turn into a really cool project,” he said. He added that the variety in Hernandez’s project will be able to give her practice with many skillsets that can help in her experience.

Hernandez has overcome many challenges in order to succeed on her journey toward completing the project.

“It was really hard trying to figure out making our stain because we had Giemsa stain available, but it was kind of old, so it wasn’t staining properly,” she said. “So then we decided to make our own stain … and that stain was beautiful.” The stain is used on microscope slides in order to identify parasites.

She went on to describe that the stain did not get properly labeled and then got dumped and had to be remade, requiring two to three weeks to mature. She also described that two of the parasite types look very similar and can be tough to identify with some types of microscopes.

“Sonia is a superstar student,” Baldassarre said. “I’ve just been so blessed to work with her. She’s incredibly hardworking, she has this beautiful passion for wildlife health and wanting to understand more about the diseases that animals get, and I’m so glad that she came to me with this project.”

Hernandez hopes that before spring break, the lab work and counting will be done so she can begin examining the data found and writing the final version of the thesis. She has presented her work at a few conferences and will be presenting at QUEST soon.