It began as an odd sort of noise. I had the study windows open during the morning of a heat wave and I heard a small, but metallic noise coming from the roof outside. My study overlooks part of the first floor roof and slinking to the window I saw a sparrow trying to pick up a roofing nail. We’ve had the roofers over twice already since we moved in a couple years back (and will have them again), and some of the nails from their work on the second-story roof landed here. I’ve noticed sparrows pecking at them before. Instead of skittishly flying away when I came up—I was only about a yard away—she still tried to lift the nail without success. She then flew even closer to me, snatched up a different nail, and flew off with it. Sparrows have, of course, adapted well to human dwellings, but what would a bird be wanting with a nail? Surely not to make a nest? It wasn’t even shiny—it was a rusty old one from the shingles replaced—since everyone knows birds are attracted to bright objects.
I’ve been a close watcher of nature my entire life. This isn’t the same as being an outdoorsman, but when I can see outside, or when I do spend valued time outdoors, I look closely. I always keep an eye out for animals on my daily jogs. And I watch animal behavior through the window when work isn’t too pressing. Still, I wonder about what a sparrow could want with a nail. The next-door neighbors moved out a couple of months ago, and I watch the sparrows on their porch roof. With no human activity nearby, they frequently gather there. They seem to be picking up bits of human detritus—even pulling at, it looks from here, nails. Now this behavior has me a little worried. I’ve read about sparrows before and despite their innocent looks, they can be very aggressive birds, even attacking and sometimes killing larger perching fowl. The idea of them weaponizing themselves is disconcerting.
Intelligence in nature is one of the last features many scientists want to admit to the the discussion. There seems to be too strong a supposed correlation with shape of the physical brain and the ability to “think,” it seems to me. I don’t know what the sparrows are planning, but clearly it involves gathering rusty old nails. Even as I was writing this I noticed sparrows chirping aggressively. Looking out my window across the street, I saw that a squirrel had crawled across an electric cable into a bushy roost where there must’ve been a sparrow nest. Sparrows began flying into the fracas from all over the place, loudly chirping. I couldn’t see what what happening because of the leaves, but the squirrel soon rushed out with a whole flutter of sparrows in pursuit. Perhaps he’d discovered their plan with the nails.