Hey, I'm Kathleen Davis, and you're listening to Science Friday.

Today on the show, it's that time of the year again, the Christmas bird count.

On the fourth day of Christmas, my true love sent to me,

four calling birds, free birds and shenter theepherdess and a part page in a pear tree.

No, not that one, the one where birders go out in flocks to record all the birds that they see in a single day.

The data that's collected during this annual holiday tradition gets sent to the National

Audubon Society, where it helps scientists understand bird population trends across the Americas.

But most of the birds you'll see are the birds that you're likely to see any other day of the

year. Think sparrows, blue jays, blackbirds, cardinals. So this year, we're turning our binoculars

towards a few wrongfully overlooked birds. Joining me now are two of our favorite birders to

share some surprising facts about birds that don't often make it to the top of the pecking order.

We have Karina Newsom, conservation scientist at the National Wildlife Federation. She's based

in Atlanta, Georgia, and author and illustrator, Rosemary, Moscow. Both of you welcome back to

Science Friday. Thank you so much for having us. Hi, I'm so excited to be here. Woo! Bird party.

Rosemary, I want to start with a bird that I know that I personally see all the time

where I live in New York, and that is the house sparrow. You recently wrote about the surprising

history of this bird. How did they end up here? This is one of my absolute favorite stories.

And I want to say I love familiar birds because of what they tell us about ourselves as opposed to just about

the birds. So this is a bird where, you know, it's all over the place, but it is not native to

North America at all. So the reason it was brought over here was as a bio control, believe it or not.

So it was brought over here because in the 1800s, there was a

horrendous problem with caterpillars, especially this one brown caterpillar called the elm spanworm

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