PENNSYLVANIA, USA — "This particular area is just the perfect storm for moving birds," naturalist Franklin Klock said.
Some areas of Pennsylvania will soon be inundated with up to 50,000 birds per square kilometer.
"We expect about 14 million birds or so to be over Pennsylvania, just a few hours after sunset," said Adrian Dokter, a migration ecologist at the Cornell Lab of Ornithology.
"These are sparrows, warblers, some woodpeckers, and so forth, even though they aren't migrating as far, but these are little birds," Klock said.
September is a popular time for bird migration, and right now, large migrations are happening all over the world. According to projections from the Cornell Lab of Ornithology, very few birds were passing through our area over the weekend but, that will drastically change soon.
"Birds are amazing weather forecasters," said Dokter. "They get assistance from the wind, and they get these little tailwinds, so it's an efficient way to travel. So, this night everything lines up."
Most of the migration happens at night. Experts who encourage you to turn off your outdoor lights, which could distract or mislead migrating birds, say you don't need to do it until about 11 p.m.
Dokter says on Monday night, bird species that typically live in Canada will visit Pennsylvania. The phenomenon is subtle, so if you want to experience it, you'll need to pay attention.
"If you try to listen very, very carefully, you'll hear this little 'chip,' and that's it. But you'll hear a lot of these chip notes."