Just 30 years ago, seeing a bald eagle in the wild would have been a rare occurrence.

But now, if you go to places like Alton or Grafton, Illinois during the winter, you're almost guaranteed to spot one.

- The bald eagle is exclusive to North America.

It lives no place else in the world except for North America.

This area in Illinois and Missouri, we have a bigger concentration of the American bald eagle than any other state in the continental United States during the winter.

- Rod Jackson is a tour guide for Alton Eagle Watching Tours.

- I grew up on a farm not too far from the river, and they were pretty rare, pretty scarce, you know, when I was young.

- From the 1940s to '60s, a pesticide known as DDT led bald eagles to become a critically endangered species.

The chemical weakened their egg shells, which lessened the survival rates of their embryos.

But in 1972, the use of DDT was banned and the bald eagle population began to grow again, with the help of some other conservation efforts.

In 2007, they were taken off the endangered species list, and according to the U.S.

Department of the Interior, the bald eagle population quadrupled from 2009 to 2020.

So the bald eagles normally live around the Great Lakes and even Ontario.

And in the fall when they realize that the Great Lakes and the rivers up north will be freezing, they cannot feed over open water.

So they come this far south because between the Winfield Lock and Dam and the Alton Lock and Dam, there's open water and they can still feed during the course of the winter.

So basically they're here from Thanksgiving to about Valentine's Day.

A large number of bald eagles in the area during the winter causes an increase in tourism to southwest Illinois.

On January 3rd, Alton hosted the Eagle Ice Festival, celebrating the return of the majestic birds.

Okay, we are on the Great River Road.

It's a national scenic byway.

At the driver's side, you'll see the Mississippi River.

That same day, Rod Jackson and his team held the first Alton Eagle Watching Tour of the year.

Attendees were taken on a shuttle to visit some of Alton's bald eagle hot spots, including the Audubon Center at Riverlands and the Mel Price Locks and Dam.

We could see as many as 12 in one place, maybe two in another place.

It was a sunny day in January in the low 40s.

It was great weather for January, but not necessarily the most ideal for eagle watching.

I guarantee you if it's a sunny, warm day in the wintertime, they're not going to be out and about.

They love the blizzard-like conditions.

If you've seen the documentaries on Alaska on PBS, then you know, you've seen the eagle fighting against the wind, but that's what they like.

We did end up seeing about three bald eagles and two large eagles' nests.

The birds were often tough to get on camera because of how far away they were, though.

Binoculars are a great way to enhance your eagle-watching experience.

Jackson says it's important to be quiet and respectful when watching the birds.

But you just have to be careful.

I think the one mistake that people make is when they see one, they want to pull over on the Great River Road.

You know, people are going 60, 65, 70, and someone sees an eagle and they stop or pull over too quickly, which can be dangerous.

But they get out of their cars, and that scares the eagle away.

And that's what we don't want.

So they're actually better off if they stay in their cars and, you know, quietly put down the window and take a photo or video.

All right, we have our first bird spot right there in the middle of the river.

If you're really lucky, you might even hear the eagles call.

And yes, that's what they actually sound like.

Most movie sound effects use a red-tailed hawk's scream for bald eagles.

Jackson says it's great to see people coming to the area to admire these iconic birds.

As I said, they were endangered at one time.

There were very few bald eagles.

That is our national symbol for American freedom.

So it's important that we preserve that and preserve them.

And I think the more people are educated and the more they learn about them, the more they respect them, because there's a whole lot to know about American bald eagle.