HOUSTON -

During sunrise and sunset, grackles are gathering at a shopping center in the Galleria area.

In the early evening, the birds start to appear in sheets. They fill up trees, line business roofs and power lines, and make pit stops on cars in the parking lots.

The big question is, why are these birds clustering around busy businesses?

“In the winter they gather in these huge congregations for predator protection," explained Mary Anne Weber, an educator for the Houston Audubon Society.

Weber says these birds actually live in Houston year round. They just gather in big volumes for the winter because their eggs have hatched and they don't need to be with their nests anymore; therefore, they can go be social with other birds.

“Being in those big groups you have all your friends looking out," said Weber, "more eyes to look for dangers.”

They gather during dawn and dusk when their predators, like hawks, are on the hunt.

Weber added they like the openness of shopping centers, and the power lines give them a 360-degree view of their surroundings.

“They also like to eat french fries and garbage that people leave behind, so shopping centers are really popular,” she said.

Weber says they aren't going to hurt you. Still, workers say the images can be unsettling.

"It's kind of surreal," described Andrew Hoskins, an employee at a Post Oak Shopping Center business. "It is kind of like that movie "The Birds". They are all plotting up on the edges of the buildings."

To shoppers they may look intimating but the birds usually leave them alone.

“Most of the time when you are walking to your car they will just fly away," said shopper Juanita Peters.

Some people even try to have a little fun.

“I saw one guy he had his jacket pulled over him to protect himself like he was being terrorized by the birds and his friends are taking pictures of him," said Michael Kronke, an employee at a Post Oak Shopping Center business.

The birds only stick around for about 30 to 45 minutes.

Businesses have to get creative on how they get rid of the birds since they cannot be harmed because they are a protected species.

Some have tried to scare off the birds with loud noises.

Weber said one Kroger in Houston sprayed grape seed oil on their trees because apparently they don't like the smell of it on their feet.