JOAN CARTAN-HANSEN, HOST: Snakes play an important role in our ecosystem, but a number of snake populations are in trouble.

A skin disease is killing snakes in large numbers.

So how do biologists track this disease and protect snake populations?

Find out.

(MUSIC) Megan Yrazabal and Samuel Johnson are out hunting.

for snakes.

MEGAN YRAZABAL, NATURAL RESOURCE TECHNICIAN, IDAHO ARMY NATIONAL GUARD: Okay, I'll grab the snake tongs.

(CAR DOORS CLOSE) I think what we will do is if you want to take a pair of snake tongs, we'll head up this direction and circle around and look for rattlesnakes, gopher snakes whip snakes, whatever we can find.

CARTAN-HANSEN: This is the Morley Nelson Snake River Birds of Prey National Conservation Area.

This area was set aside to protect the largest concentration of nesting birds of prey in North America.

YRAZABAL: Within that, we are on the Orchard Combat Training Center.

This is a military training facility that lies almost solely on public land.

It's on BLM land.

So, there's a lot of things happening in this area.

CARTAN-HANSEN: Yrazabal and Johnson are biologists who work as natural resource technicians for the Idaho Army National Guard.

YRAZABAL: The most important reason of why we should care about snakes specifically here on the NCA is they are prey source for the whole reason this conservation exists.

They are prey source for birds of prey.

So, the birds need to eat.

Along with that, they also feed on small rodents, which carry diseases that can make people sick, things like hantavirus.

CARTAN-HANSEN: So, what's the first thing you do when you are on a snake hunt?

You look around.

YRAZABAL We take incidental observation.

So, this would just be a snake crossing the road.

We'll take a GPS point.

We collect all of that data and we pass that on to Idaho Fish and Game for their database CARTAN-HANSEN: They also check out places where particularly rattlesnakes like to hang out.

YRAZABAL: So, a hibernaculum is essentially a denning site.

Around here, they are collapsed lava tubes for the most part.

And the reason snakes hone in on those areas is it's a consistent temperature year-round.

So, in the summer, it stays about 65 and in the winter, it's about low sixties.

So, when we're out looking for snakes, the first thing we do is we take a pair of snake tongs.

We usually work in pairs for safety, if they're venomous.

We'll grab the snake, usually it's somewhere in the middle of the body of the snake.

You want to be cautious of getting too close to the head and getting too close to the tail.

You don't want to hurt them.

So, one person will grab the snake in the middle.

Somebody else will grab kind of closer to the head and we'll grab a tube that's the proper size and we'll start to kind of feed the head into the tube.

The first thing we're going to do is scan with a pit tag reader to see if they've been pit-tagged.

A pit tag is essentially a microchip, so, the same thing that would be placed into, like, your dog or cat.

It's about the size of a grain of rice.

If there's no tag found, next thing we're going to do is swab them for snake fungal disease.

Snake fungal disease is a disease that affects the keratin of snakes.

So, this is impacting their scales.

This is a disease that was discovered in early 2000s on the East Coast of the US.

It's slowly making its way to the West Coast.

CARTAN-HANSEN: Snake fungal disease poses a significant threat to some types of snakes.

It's difficult to control and can lead to death.

And many snake populations already are in trouble because of loss of habitat, climate change, and humans killing them off.

So, to protect snake populations, it's important to test for this disease.

YRAZABAL: This entails swabbing eight times down one side of the body and eight times down the other.

Each of those samples go into their own tubes, and those tubes are sent off to the lab in Illinois for processing.

CARTAN-HANSEN: They also inspect the snake's skin for disease.

This one seems okay.

YRAZABAL: We also will measure the snake.

So snout vent length is basically from nose to bum and we'll see how long that is in millimeters.

Snout vent length can be an indicator of age of certain species of snakes, which is why we record that.

And then, we'll also sex the snake.

So is it a female?

Is it a male?

CARTAN-HANSEN: They finish up by putting in a pit tag.

The tiny tag gets injected under a scale and gets superglued into place.

A pit tag reader will now give this snake its own unique number.

YRAZABAL: And the final step is, scan it and make sure you get the same number.

And the snake is ready to be released.

CARTAN-HANSEN: Yrazabal and Johnson put the young rattler back where they found him.

YRAZABAL: Sometimes they need a little encouragement.

If you want to lower that tube.there you go.come on buddy.almost out.

alright, back where you came from.

Perfect (laugh).

CARTAN-HANSEN: Should you want to go looking for snakes, Yrazabal has a few safety tips.

YRAZABAL: Be very aware around rocky areas.

Snakes tend to congregate in these areas.

So, make sure you're stepping over rocks.

If you are going to flip a rock to look underneath it, make sure you are flipping it toward you.

That way a snake has the chance to get away from you instead of at you.

If you drop anything in rocky areas, don't reach barehanded in there.

You just don't know what's in there.

I think a lot of people are afraid of snakes, but they're very misunderstood and there's no reason to fear snakes or even venomous snakes.

You know, rattlesnakes have rattles.

They want to warn you.

They don't want to bite you.

Most of the time, when you approach snakes, they're going the other direction.

They don't want to come after us.

They don't want to hurt us.

Alright, you want to take the snake tongs and I'll get the rest of the equipment and we will call it a day.

If I were a kid, I would want to do what I do because the opportunities are endless.

There's so many opportunities to work in conservation.

I get to also work with the military, which is pretty unique.

If we if we want them to be here for our kids and their kids, somebody has to step in and monitor them and make sure everything is going well for the species.

I was surprised by how many whip snake sheds there were.

That was a good day.day.

If you want to learn more about snakes, check out the Science Trek website, you'll find it at ANNOUNCER: Presentation of Science Trek on Idaho Public Television is made possible through the generous support of the Laura Moore Cunningham Foundation, committed to fulfilling the Moore and Bettis family legacy of building the great state of Idaho.

By the Idaho National Laboratory, mentoring talent and finding solutions for energy and security challenges, by The Friends of Idaho Public Television and by the Corporation for Public Broadcasting.