The path of a pest
Photos by Kathy F. Atkinson and and courtesy of Matthew Siderhurst | Photo illustration by Jeffrey C. Chase June 11, 2026
UD and USDA researchers use lightweight, inexpensive tag method to track mosquitoes to prevent mosquito-borne diseases
It’s an insect everybody loves to hate.
Pesky mosquitoes will be out in swarms as the weather warms up across the U.S. — and their bites aren’t just itchy. They can transmit pathogens that can cause diseases like West Nile virus, Zika virus and malaria, to name a few.
Scientists see a solution: understand mosquito movement behavior and how they operate. Then they can tap into effective ways to control mosquito populations and prevent mosquito-borne diseases.
“As medical entomologists, we want to increase public health preparedness and reduce transmission of vector-borne diseases to humans and animals,” said University of Delaware assistant professor and medical entomologist Jennifer K. Peterson.
To understand mosquito behavior, scientists need to be able to see what they’re doing in the wild. They’ve long been able to put tags on and study animals such as fish and birds. But until recently that hasn’t been possible with mosquitoes.
Peterson teamed up with the U.S. Department of Agriculture’s Agricultural Research Service on a new study published in the journal PNAS Nexus detailing the use of tiny lightweight devices called harmonic radar tags, which harness a radio frequency to track insect movement. The findings shed light on the capability to use these devices to learn more about mosquitoes.
Scientists have tried different methods to track mosquitoes, like trapping them with carbon dioxide or even using dogs to sniff out hiding mosquitoes. But because the insect is so small, it’s been hard to find a method that works.
Enter harmonic radar tags. Since the 1980s, scientists have used them on larger insects such as beetles, moths, bees and wasps. They’re affordable and handmade — consisting of just two flexible wires and a semiconductor device called a diode. Scientists assemble the tags, glue them to insects and the insects can move freely and fly while a handheld transponder often used for backcountry rescue locates them through a beeping signal.
Matthew Siderhurst, a research biologist with the USDA-ARS Pacific Basin Agricultural Research Center based in Hawaii, has utilized harmonic radar tags to track yellow jackets, coconut rhinoceros beetles and spotted lanternflies, among other insects, finding the insects could still move and fly with them. Siderhurst supported the team of scientists who used the trackers to locate murder hornet nests in Washington, helping to eradicate the invasive pest in the U.S.
With the technology’s success, Siderhurst wanted to see if it could work on an even smaller scale.
“Mosquitoes are three times smaller than anything else we’ve ever done,” Siderhurst said. “They’re the deadliest animal in the world. If we don't have a way of understanding their biology, how can we work on control?”
Siderhurst captured female tiger mosquitoes, which are common and invasive in Hawaii as well as Delaware. Under a microscope, his technician, Anika Hurst, glued the HR tags vertically on the back of their thorax, between their head and abdomen.
The size of the wires and the diode have varied based on the insect. The diodes used on mosquitoes are so small, scientists could fit three to four diodes inside of a 12-point-font period.
Researchers conducted 12 experiments in a lab, in an outdoor screen cage, in a coffee field and shaded parkland.
“We released the mosquitoes, and then we walked around waving these detectors, trying to find where they’ve moved to,” Siderhurst said. “We marked that with flagging tape, and then we came back and we did measurements, trying to figure out how far they flew.”
Mosquito take-off animation: https://capture.udel.edu/media/1_e4b2ij2z/
Mosquitoes were documented flying about two meters above ground in the coffee field, landing less than one meter above ground. Trees in the coffee field hindered longer flights, while shaded parkland experiments gave more insight into how far mosquitoes could move with the tags in the open.
“The major finding is we could do this,” said Siderhurst, acknowledging HR tags’ capability to track mosquitoes. “[Tiger mosquitoes] don’t move that far. That’s not new. But the HR tags confirmed we’re looking at what we think is real behavior.”
The findings unlock new pathways for researchers to examine mosquito behavior.
“There is so much we don’t know about mosquitoes — how they move, when they’re coming after us, where they hide, what causes them to move,” Siderhurst said. “The research opens up new ways to get this information.”
The tags aren’t perfect. In the first 24 hours after they were attached, 60% of the mosquitoes died, which Siderhurst wasn't happy to see.
“We want to see the mosquitoes move as naturally as possible,” he said, acknowledging the wires could get in the way of mosquitoes’ flight. Also, mosquitoes that feed on blood are capable of carrying more weight than non-blood-fed mosquitoes.
In putting together the scientific paper, Siderhurst sought Peterson’s vector-borne diseases expertise.
“The gray area we’re trying to fill with HR tags is what happens in between the moments that insects bite us or show up in our homes,” Peterson said.
To Peterson, this research is just the beginning when it comes to answering crucial questions about vector-borne diseases.
“Now, let’s optimize and use this to answer critical public health questions,” she said.
Her lab is using HR tags to study kissing bugs. These insects can transmit the Chagas disease-causing parasite. Chagas disease can cause cardiac and gastrointestinal symptoms in people.
“Kissing bugs are often found in low densities — they have this distribution that can be difficult to predict,” Peterson said. “Harmonic radar tags are the only tags small enough to attach to them. They’ll help fill in a lot of unknowns about them: What are they doing between feedings? Where are they going?”
One of Peterson’s master’s entomology students, Hanna Cortes, is using harmonic radar tags to track kissing bugs in residential areas of Florida — where they’re more abundant compared to Delaware.
Her research last summer was the first time HR tags were used to study kissing bugs. Cortes found the tags worked. Now, she is building an enclosure where she’ll be able to observe kissing bugs with HR tags and kissing bugs without them, to get a better idea of how much HR tags affect the bugs’ movement and behavior.
“I want to know what they’re up to,” Cortes said. “Knowledge is power. Knowledge is protection when it comes to diseases. Knowing what they’re doing in these areas and having that information is hugely helpful.”
The research, Employing tiny harmonic radar tags to study mosquito movement in natural environments, was published in the journal PNAS Nexus, Volume 5, Issue 3, March 2026. Authors are Matthew S. Siderhurst, Anika L. Hurst, Pei-Shih Liang and Nicholas C. Manoukis of the U.S. Department of Agriculture and Jennifer K. Peterson of the University of Delaware. Funding came from the USDA’s Agricultural Research Service.
Contact Us
Have a UDaily story idea?
Contact us at ocm@udel.edu
Members of the press
Contact us at mediarelations@udel.edu or visit the Media Relations website
