Matthew Barnes, Ph.D., an assistant professor in Texas Tech’s Department of Natural Resources Management, is looking for a criminal in the Sabine River. This criminal left behind DNA, in the form of skin cells, that Barnes will utilize to identify the suspect.
However, in this case, the criminal Barnes is looking for is not human. It’s Silver Carp, an invasive fish species in Texas’ waterways.
Barnes is an aquatic community ecologist who has an interest in invasive species. Although his lab uses a variety of tools to study invasive species, one of his favorite management tools is testing for environmental DNA.
Environmental DNA, also known as eDNA, is the genetic material organisms shed into their environment like skin cells, blood, feces and other bodily fluids, Barnes said. The material provides clues that a particular species is present in a particular environment.
Barnes said there are benefits to using eDNA testing as a management tool. It has been proven to be cost effective in searching for invasive and endangered species. It can be a less intrusive tool when looking for a species in a sensitive ecosystem. It can also be useful when looking for an invasive species with low population numbers that has been recently introduced in an area.
“The first step in studying or managing an organism is to know where it is,” Barnes said.
Barnes said managers can use tools like eDNA testing in order to start the research or management of an organism. Searching for an organism can be costly, time consuming, and work intensive. Barnes said developing eDNA testing as a new tool is important for aquatic community ecology, invasive species management, and natural resources management.
We are applying eDNA to new species in this case, and that will provide new opportunities for natural resources management. Matthew Barnes, Ph.D.
Although eDNA testing has most frequently been used in aquatic systems, Barnes and his graduate students are applying eDNA testing in new ways for both aquatic and terrestrial systems.
New researcher brings new ideas
Mark Johnson, a graduate student in Tech’s Department of Natural Resources Management, is a part of Barnes’ lab and is in charge of researching eDNA testing in terrestrial systems. His research is being done with help from across the College of Agricultural Sciences and Natural Resources. Robert Cox, Ph.D., and Peter Dotray, Ph.D. are assisting with the research.
Johnson said he grew up in rural Pennsylvania surrounded by trees, mountains and rivers. After taking a botany class during his undergraduate education, he realized how much he liked natural resources management and chose to pursue a master’s at Tech.
Johnson said he is looking at airborne eDNA and how it works as a survey method for plant communities.
“My work is looking at plant communities, how eDNA can be used to identify plant communities and how that all fits in together on a landscape scale,” Johnson said. “I think that it’s really important to try and find uses for eDNA that aren’t just finding an organism and reporting on it.”
Johnson said he has set up various dust traps in the field to collect airborne eDNA. He visits the testing sites every two weeks to wash the dust traps out. He then takes the water back to the lab, filters it, and extracts DNA to run tests on the samples.
Johnson said he hopes his research will provide a new way for wildlife biologists and natural resources managers to utilize eDNA testing in terrestrial systems.
This research is entering new territory. Johnson is the first to compare a traditional plant survey with an eDNA survey. Because this is new research, there are a lot of unknown aspects to his research.
One of the unknowns is they do not know how far eDNA can travel through the air, Johnson said. They are unsure what species are able to produce eDNA. They do not know whether pollen spreading species or species that are insect pollinated produce eDNA. Johnson said he believes this is what sets his research apart from others.
“I think the research that Mark is doing in particular is expanding this method, to say, terrestrial plants,” Barnes said. “We are applying eDNA to new species in this case, and that will provide new opportunities for natural resources management.”
Lab’s new research
Barnes said although his lab is interested in applying eDNA testing in different systems and species, another thing that sets them apart is their focus on the ecology of eDNA. The unique focus on the ecology of eDNA is another new way his lab hopes to impact natural resources management.
The ecology of eDNA focuses on the interactions between genetic material after it is shed from the organism and the role the genetic material plays in its environment, Barnes said. The research being done on the ecology of eDNA has helped distinguish Barnes’ lab from other natural resources labs in the country.
Barnes said he has had the opportunity to filter and look for eDNA in thousands of liters of water in very diverse systems, ranging from the Chicago area waterways and Great Lakes to the reservoirs and streams of Texas.
Although he has spent most of his research in aquatic systems, Barnes said Johnson brings enthusiasm and an expertise in terrestrial plant systems, and he has pushed Barnes out of his typical work in aquatic systems.
“He also challenges us to develop and learn new skills in terrestrial plant census and ID,” Barnes said, “and it has been a lot of fun having him on board.”
Pushing the boundaries
Barnes said his lab is pushing the boundaries and increasing the amount and type of information researchers can gain from eDNA testing. He said this is an exciting time to be in research.
Barnes said it is stimulating to be asking questions that nobody has asked before, and it is compelling to be producing knowledge that nobody has produced before.
Barnes and Johnson credit Tech for giving them an opportunity to do research.
“One of Texas Tech’s main roles is providing an area for us to help build on its foundation,” Johnson said. “It has the resources we need, areas where we can go study environmental DNA, and the work being done here is really helping to build on what we know about eDNA and expand it broader as a field.”
Tech has provided the resources for Barnes’ lab to continue their work searching for invasive fish and zebra mussels in Texas, detecting threatened and endangered fish species in New Mexico, and looking for the vector for white-nose syndrome in bats in Louisiana. Barnes and Johnson look forward to expanding the natural resources field with their research, and they will continue to spend their days searching for traces of criminals.