Hey, it's Flora, and you're listening to Science Friday.

In the early 1800s, Lewis and Clark loaded up their camping gear and journals and headed west to the Pacific, recording what they saw along the way.

The expedition, partly about natural history, partly about future colonization, returned with a record of biodiversity in the early 1800s in the now United States.

200 and some years later, a new expedition is headed west to find out how wildlife populations have changed over the centuries.

Dr. Roland Kay's and his team are traveling the same route

using camera traps and enlisting local scientists to document the wildlife along the way.

Roland Kays is the head of the biodiversity lab at the North Carolina Museum of Natural Sciences,

and he's on the line to give us an update about his trip and what they're finding.

Hey, Roland, welcome to Science Friday.

Hey, great. Thanks for having me.

Where are we finding you today?

Right now, I'm basically in a van down by the river.

We're on the Missouri River, which is most of the route that we're following.

We're presently at a dam, Fort Peck Dam in Montana.

What are the days like? What are you doing all day? Well, we are driving and kayaking along the

Missouri River. So we're hitting some of the more significant, more interesting, more beautiful

parts of the river in canoes and kayaks, and otherwise we're driving. And we're obviously looking for wildlife ourselves,

but we're also collaborating with a team of scientists, over 100 scientists across the country

who are running camera traps. And these cameras let us document in a systematic way what animals

are living all on the route today.

What are the big questions that you're trying to answer? Well, the big question is,

is how is wildlife doing today? And then comparing that against what Lewis and Clark observed.

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