SAN RAFAEL, Calif. (KGO) -- If you have driven through Marin County in the past three weeks, you may have seen a spectacular sight in the sky -- thousands of starlings involved in murmurations.
The birds fly together in massive groups, creating all sorts of shapes in the sky before roosting, or going to sleep in the trees below.
"It's like 50,000 birds flying in unison," said Rob Cochran, a resident who came to watch the birds Tuesday night.
"Millions of birds flying in different formations like swooping through!" said birdwatcher Michelle Polli.
On Tuesday night, word had gotten around and dozens of bird watchers took to the CVS parking lot near the Northgate Shopping Center to try and catch a glimpse of the free-wheeling flock.
"I think I'm becoming a bird lover. Birds are pretty cool!" said animal enthusiast Allison Jacobs.
Ilana DeBare of the Golden Gate Audubon Society explained the practical reasons behind why the birds are involved in these murmurations.
"They can come from 5, 10, 20 miles away, and they form these big gatherings because they are safer in numbers, DeBare says. "If you are a lone starling and there is a predator like a falcon coming at you, you are much safer in a group of a thousand or ten thousand other birds."
Experts say the birds will then roost, or sleep close together as a way to stay warm on cold winter nights.
While the excitement level may have been high in San Rafael on Tuesday, for the second night in a row, there were no birds.
Many who showed up to watch the starlings say that's okay because they've seen the birds over the course of the past few weeks.
"I almost crashed my car," says Jacobs. "All of a sudden, I saw in the sky what just looked like these swarms, these dark clouds like clustering in. And then I looked closer and was like, those are birds!"
"Like synchronized flying in the sky up as far as you could see, and then collapsing on themselves. It was just amazing, absolutely jaw-dropping stuff," says Cochran.