Associate Professor Kristina Ramstad is participating in work around the globe to preserve the American wood stork (Mycteria americana), an at-risk species that has recently been downgraded from endangered to threatened. By studying their DNA, Ramstad and her students will determine how many populations exist worldwide and how they are connected demographically and genetically, information that can be used for applied conservation management.
"Wood storks have a complex system of movement," Ramstad explains. "We are using genetic tools to determine the makeup of the colonies and whether they function like one big population or have to be managed separately."
Ramstad first began capturing and collecting tissue samples from stork chicks in 2016 and received funding for genetic sequencing from the National Science Foundation in 2021. Because wood storks are so widespread, she collaborates with the S.C. and G.A. Departments of Natural Resources, the U.S. Fish and Wildlife Service, and the Jacksonville Zoo, as well as other universities and museums in Cuba, Brazil, and Costa Rica, to obtain genetic samples from colonies around the world.
Ramstad and her students monitor a colony of wood storks located on private land in Georgia and exchange data and tissue samples with the broader group of researchers. Students are heavily involved in the field, where they capture and band the birds, take measurements, collect blood and feather samples for DNA, and monitor the number of fledglings per nest. Students also work in the lab, extracting DNA, preparing libraries for sequencing, and analyzing data.
Senior Madison Zimmerman, one of Ramstad's students, says, "I have been able to experience the full scope of what goes into a complete research project. My research on wood storks has involved a combination of fieldwork, where I climbed trees to collect biological samples, lab work, such as library preparation for sequencing, and subsequent bioinformatic analyses."
Ramstad explains that the team's preliminary results indicate that wood storks are one big population. "There is very little and potentially no genetic divergence between birds in the United States and those in Brazil," she says. "The population is high gene-flow, meaning that a lot of individual birds are moving around between and reproducing in different nesting colonies."
This is important to conservation efforts because it indicates wood storks' resilience to climate change. Ramstad says, "If we have colonies that suddenly disappear, it is very likely they will be recolonized later because the birds are moving around a lot. I've never worked with a species like this with really specific needs for hydrology that helps them feed. Because they are so good at finding what they need, they go somewhere else. They are slowly moving north, likely because of climate change and degradation of their habitat in the Florida Everglades."
Although wood stork populations have decreased significantly in Florida, there are large numbers in other places around the globe. As a result of these findings, Ramstad believes they could be removed from the threatened species list entirely.
In addition to its contribution to conservation efforts, this project offers significant benefits to USC Aiken students. "There are a lot of different aspects to this project, from fieldwork where they catch the birds, to lab work, bioinformatics, and data analysis. The international and conservation elements resonate with students because they understand what they're doing and why," Ramstad says. "In having all these elements, allows students to try them all on and figure out what they like and don't like."
Zimmerman will graduate in December 2023 and plans to build upon these skills in graduate school, where she will pursue a Ph.D. in molecular biology and genetics. She says, "This experience has been instrumental in preparing me for the next step by providing hands-on exposure to bioinformatic methods, allowing me to present my research at state and national meetings, and giving me the opportunity and confidence to foster connections within the scientific community. All of this will be invaluable in my future academic and research endeavors."
For more information, contact Leigh Thomas, thomas29229@yahoo.com