The path of a pest

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.