
It was February 14th, 2019. As the sky blackened and the temperature dropped, I spent the lonely evening walking around in the snow on campus.
At about 6 p.m., I was passing by Black Hall when I suddenly saw a large bird fly into a tree. It was a raptor with white underwings and a silent flight!
My first thought was that the bird of prey was a Great Horned Owl (it was pretty dark out), but I also considered "Red-tailed Hawk" as a possibility. To sum it up, I was unsure, so I decided to try a little experiment.
I walked directly under the bird's perch and gave a high-pitched series of hoots: "hoo-hoohoo, hoo, hoo!" The sitting raptor, whatever it was, seemed to straighten up. Then, to my utter astonishment, it hooted back - looking around all the while!
The owl (a Great Horned Owl male - more on this later), gave a lower, more trembling series of hoots: "hoo-hhoo, h-o-o-o, h-o-o-oh!"
I kept hooting and he consistently responded approximately three to five seconds later. He also leaned forward and puffed up his white throat patch. I could see its snowy glint even in the evening light!

This back-and-forth hooting interaction happened about five times over the span of five minutes. While I hooted, the owl kept looking down at me, then looking back up. From my perspective, he seemed clearly interested in my behavior!
At one point, I walked around the tree (behind the owl), and hooted some more. The owl seemed to look for me, then hooted back. After a few more moments had passed, I decided to leave the bird in peace. I came back several minutes later, but the owl had melted into the night.

Once I returned to my dorm room, I opened my trusty book: The Backyard Birdsong Guide: Western North America. According to this guide, male and female Great Horned Owls duet, or sing complementary songs with each other. The male has deep, soft hoots, while the female has higher, louder hoots (not unlike the voice differences of adult humans).
What I gathered from this was that the male Great Horned Owl I saw likely thought that I was a female Great Horned Owl duetting with him! (In other words, I was a potential mate).
Not a bad way to end Valentine's Day - courting an owl!