Miscellaneous Bird Questions with Dr. Matt Reetz

All of these questions were submitted by a future fourth grader at Elvehjem Elementary School, and our first question is how many different bird species are there?

Oh, I love this question.

So cool thing about this is that scientists aren't totally sure of the, the number.

So the best answer right now is somewhere around 11,000 species of birds.

Whoa.

It's a lot, yeah.

It's not as many as beetles, 'cause there's-

[laughs]

... somewhere around 400,000 known species of beetles, but it's still a lot.

Uh, the tricky part about figuring out how many bird species there are is that the number keeps changing.

Sometimes scientists will discover a brand-new bird, which is rarer and rarer nowadays, but no one had ever maybe found it before, and scientists find a new species of maybe five to 10 in a really good year, but that's very... that's a really good year.

That's usually pretty, pretty rare that th- this happens.

Whoa.

Um, and this is usually in mostly in remote jungles and rainforests and p- places that are really hard for humans to access.

So they might get in there with a, I don't know, a machete and find a new-

[laughs]

Uh, but sometimes also the opposite happens.

Scientists thought that were two birds were the same species, but then they looked at their DNA and then they realized that those birds are actually different from each other, and that's what's called a split.

And in 2025, for example, scientists agreed to split the warbling vireo into two species, the eastern warbling vireo and the western warbling vireo, so now there's two species that were originally one.

And sometimes even the opposite of that occurs.

Two birds that were thought to be different species get lumped together.

So they've looked at their DNA again and in 2024 there were two species of what's called a red poll, that's like a finch, and they were lumped into a single species called the red poll.

[laughs]

So, um, and then the other part of this that's obviously very sad is that sometimes birds go extinct.

Mm.