Fulbright Foreign Student Sergio Cabrera-Cruz discovered the University of Delaware through the published works of Jeff Buler, UD associate professor of wildlife ecology. Cabrera-Cruz had first taken up an interest in migration during his undergraduate career and later spent significant time monitoring bird migration related to wind farm development during his master’s program at the Instituto de Ecología A.C. in his home country of Mexico. “I wanted to keep delving deeper into the methods of understanding bird migration,” he said. “Dr. Buler was not applying the same exact method or using the same tools that I had previously used.” It was the use of these tools that would eventually bring Cabrera-Cruz to UD. With Buler as his adviser and research collaborator, the pair are working on a project using the only tracking radar of its kind in the Western Hemisphere. Standing 12 feet tall, the World War II-era instrument will allow Cabrera-Cruz to better understand how the anthropogenic input of light impacts birds during migration, a key stage in their life cycle. “This radar allows us to collect data on individual birds and how they behave during flight. The tracking radar will collect detailed information on how high in altitude birds are flying, how fast, and what they are flying through,” he said, adding, “With this tool, we can study the reaction of birds in flight to almost anything we can think of.” While other types of tools, like weather radars, can track migratory groups on a broad scale, marine radars, like the one that Cabrera-Cruz and Buler use, track migration in a much more localized way. The team has set up shop at a farm and bird banding station close to Chestertown, Maryland, where Cabrera-Cruz has traveled nearly every night of the semester. At the banding station, he has installed streetlights, turned on for intervals of three to five days, a thermal camera and auditory recorders aimed to capture migratory movement and sound in the dark. Just a couple of minutes away, Cabrera-Cruz operates the radar to identify individual birds and then tracks their movement in three dimensions. “I scan the sky looking for targets and then the radar does its job tracking and recording the data.” Once this year’s migratory season has ended, Cabrera-Cruz will spend his time analyzing the data, cleaning it and transferring it to Google Maps. From here, the team will be able to better understand what impact, if any, those streetlights had on the migrating birds overhead. “Given that migration requires such high levels of energy of birds, we think that any disturbance to their flight behavior, any extra cost we add that affects their performance, could have consequences,” said Cabrera-Cruz. The group postulates that streetlights could possibly cause birds flying through the night to land for rest early, costing them precious time and resources. Other UD researchers in the College of Agriculture and Natural Resources have identified that those birds who make it to their nesting sites first have the best shot at food and the best chance for survival. If, in fact, the group’s study indicates that birds do react to streetlights, they hope to inform future policy intended to defray the unwanted effects of the lights which crowd parking lots, urban and suburban areas everywhere. Buler and Cabrera-Cruz will continue data collection during the migratory seasons in spring and fall 2017 after a successful crowdfunding campaign.