Major support for Oregon Field Guide is provided by... [ ♪♪♪ ] WOMAN: Come on!

There he is, there he is, there he is.

[ exclaims ] Get him out of there, buddy!

Good boy!

[ laughing ] WOMAN: Whoo, high five!

Yeah!

JAHN: Next, on Oregon Field Guide: So it's kind of a cool, rainy night here north of Portland, and you'll see behind me a bunch of folks that look like crossing guards, which is exactly what they are... but not for people.

They're here for red-legged frogs.

GILFILLAN: A rainy night in northwest Portland might not be everyone's idea of a good time, but it does attract frogs... WOMAN: You're going to need a spokesperson for your species.

...and the people who care about them.

These are northern red-legged frogs, and these local natives are getting a little harder to find these days.

MAN: It is an Oregon species of concern because populations are in decline and probably the main reason is habitat loss.

Colin MacLaren is a wetland ecologist with Portland General Electric.

Near this PGE substation north of Linnton, red-legged frogs are neighbors.

So they spend their adult life up in Forest Park, which is just to the south of us.

And around December or so, they start to migrate down to breed.

This wetland is known as Harborton, and it's the site of one of PGE's long-term restoration projects.

It's a 53-acre habitat preserve that's within seven, eight miles of downtown Portland, and it's one of the more significant breeding sites in the region.

Frogs lay their eggs in these gelatinous masses.

The eggs incubate for a few weeks in the wetland while mom and dad head back uphill to Forest Park.

And that migration part is where things can get... well, deadly.

So the biggest impediment to the frogs coming to the site is Highway 30, which is a busy roadway.

Enter the dedicated volunteers of the Harborton Frog Shuttle, also known as the frog taxi.

Philip Fensterer is one of its volunteer leaders.

I am the Sunday night frog captain, frog taxi captain.

And this is the frog log.

So that's where we store all of our frog data.

The frog log records how many frogs came downhill to breed in early winter.

For the season, we're at 155 females and 1,400 males.

And now, in early March, it's time to get those breeders back uphill to Forest Park for the summer.

We're here to make sure they get across Highway 30 safely.

Otherwise it becomes real-life "Frogger."

But to keep the frogs from becoming video-game victims... Philip and his team will have to catch the frogs.

It's a frog fence.

It slows them down because it's really surprising how fast they move.

So we'll have several volunteers and myself watching for the frogs coming out of the wetland and we'll be intercepting them.

Almost there.

There we go.

Hey.

Welcome back.

Good to see you.

Just before nightfall, volunteers begin to show up.

We had an amazing night on the 25th.

Cameron was with me, and we were out here until 11 o'clock at night.

It was insane.

There were frogs everywhere.

Our temperature right now is, uh, 47.4, so that's a good temperature for frogs.

It's raining, so they like that too.

So we've got pretty good frog conditions tonight.

All right, y'all, we can get started.

Frog spotting can be tricky.

MAN: For the most part, we're just trying to see for anything that stands out or looks back at you.

While cold and wet are ideal conditions for frogs... No luck.

Yet.

...this evening seems to be getting off to a slow start.

This is almost too comfortable.

[ chuckles ] But the slow start hasn't dampened Sierra LeFever's enthusiasm.

I love frogs.

I found out about this, I emailed, I was like, "I know you guys are full up.

Is there any way I can get in on this?"

And they had an opening, so I've been out here five times.

I love it.

I could be out here all night.

While we're waiting for something to happen, it might be a good time for a bit of history.

One rainy night in 2013, some local folks were heading down Harborton Drive and noticed a bunch of frogs hopping across the road.

PHILIP: And the next day is when they saw a lot of roadkill, and that's when it really kicked in that we needed to start doing something.

And the frog taxi was born.

Oh, yeah, we got one.

The party finally gets jumping when Cameron finds the first frog.

CAMERON: This is our target species, the red-legged frog, and it was headed across the road.

So we saved this little guy's life.

Yeah, absolutely.

PHILIP: Every night is different.

It's sort of the luck of the draw as far as the conditions being right.

But, uh, I am optimistic.

Oh, there's one right there!

Hello, little guy.

That's three.

There's two right here.

He's pretty squirmy.

Oh, there he goes!

It was on the fence.

The fence is doing its job.

SIERRA: Oh, there's a tiny one.

WOMAN: Yeah, that's a chorus frog.

A couple hours after sundown and seven frogs captured... PHILIP: Five and two?

WOMAN: Five and two.

...the taxi is on its way, albeit cautiously.

I'm kind of creeping along.

When you see a roadkill, it kind of crushes you.

Chorus frog in the road right there.

That's not going to happen on my watch.

In a few minutes, Philip and his precious cargo are across the highway and headed uphill to Forest Park.

The commute is just a few hundred yards, but this taxi ride makes all the difference.

We're going to walk up the hill just a little bit.

I have a spot where there's some nice sword ferns for them to start out in, and they can spread from there.

With the tip of a bucket...

Here we go.

...and some words of advice... Make good choices.

...the frogs are on their way home.

But on the way back down, volunteer Alex Terlecky finds some females still trying to get downhill to the wetland.

These are some of the late-season stragglers, it seems like.

The females are slightly rounder than the males because they carry the eggs.

And so, pretty good night tonight, having three females come down the hill.

I was surprised.

PHILIP: All right, thank you for being out here.

Once the downhill frogs are loaded, the taxi heads back to the wetland.

And so it's a little bit of a back-and-forth.

It's a shuttle.

It's a frog taxi, it's a "fruber."

As in "frog Uber."

If this seems like kind of a lot of effort, well, it is.

We put up thousands of volunteer hours in every winter, and I don't know how sustainable that is.

The Oregon Wildlife Foundation is leading an effort to build the frogs an underpass.

But building a tunnel under a highway is expensive.

And since this isn't an animal that's going to damage your car if it gets out in front of you, it's a less compelling financial priority.

Ready to go get in the water?

Go that way.

So until these obstacles are tackled, the resident frogs of northern Forest Park can hop on the frog taxi.

If I can save a frog and the team can save frogs, we're going to do the best we can.

[ ♪♪♪ ] It's been well over a decade since the last dams came out here along Washington's Elwha River.

The waters now run free from the Olympic Mountains all the way to the sea.

Now, when this dam project was first conceived, no one could actually say for sure how it would all turn out.

But enough time has gone by that we can now show you the results.

MAN: The song we're going to sing is the salmon song.

[ singing in Klallam language ] [ drums begin beating and singing continues ] GORDON: It's a rainy morning in October, and over ten years have passed since dams were removed from Washington's Elwha River.

[ laughing, chattering ] The Lower Elwha Klallum Tribe is gathering to celebrate their first day of fishing on a free-flowing Elwha in over a hundred years.

[ singing in Klallam language ] But who would've thought?

Who would've thought that this day would come?

I remember when I was a young kid, my mother told me, "You have to take those dams out, son.

You have to help take those dams out!"

She said, "You have to do it with the tribe."

The first dam was huge to me.

I was just a little 6-year-old, and it was just a big monster in the middle of the river.

And, "How am I going to take that out?"

FRANCES: It took us a hundred years.

A hundred years to see what has transpired today.

And that is something that I'll never forget.

And the kids, they will be able to say that they were down here on the historical day, witnessing what has taken place in the river, of the opening.

Hold it!

Hold it?

After the dams were out, the tribe waited for the salmon to reestablish themselves before opening the river to fishing.

RUSS: You know, we waited so long over the hundred years just to get the dams out, and then we waited another 12 years for the fish to recover enough in numbers and population that we could fish again.

And it's very important, I think, to our community that we're back in the water.

FRANCES: Our tribal membership was the ones that stepped forward and said that we're willing to take the sacrifice, knowing that it was their livelihood and their income.

RUSS: Today, we have a truly wild and free Elwha River, and hopefully all of the species come back.

We're trying to recover the whole ecosystem.

WOMAN: So we are standing on the remnants of the Glines Canyon Dam.

These concrete blocks are the abutments of the old dam.

The Elwha was the largest dam removal project in U.S. history at the time, with the first dam coming out in 2012 and then the larger Glines Canyon Dam in 2014.

They had this barge out on the reservoir with a giant rock drill on it.

The idea was to let the sediment come out in pulses instead of all at once.

One of the first things the Elwha River did after being released from the dams was reclaim some of its former territory.

The river resumed finding its natural channel and the road happened to be in that natural channel, so it's just... [ chuckles ] the rewilding of the Elwha.

The river runs through Olympic National Park.

Heidi and Josh are fish biologists helping document changes in the river ecosystem before and after the dams.

They hike to one of the reaches just above the old dam site where Heidi uses an antenna to listen for signals from radio-tagged fish.

They have tagged salmon, steelhead, and bull trout.

The signals give some idea of where the fish are in the river during different times of year, but Heidi and Josh also get in the river to collect data and verify with their own eyes.

One of our methods for measuring this fish response as they reestablish in the Elwha is snorkel surveys.

We get in the river with our drysuits and neoprene because the river is glacial-- it's pretty cold.

We're looking at fish, counting everything.

You feel kind of like you're flying through the river.

I wish I was part fish.

It's incredible what these salmon and steelhead and trout can move through.

These rivers are the lifeblood of these areas, and with the dams in place without any fish passage, it really just-- it broke the river.

And it was broken for over a hundred years.

We're seeing a lot more response from wildlife coming back down to the river.

We have, you know, more marine-derived nutrients coming up the river as salmon and steelhead return.

When these fish swim upriver to spawn, they bring nutrients from the ocean to the Elwha in their bodies.

It's a bounty that feeds bears and eagles and even makes its way into the roots of trees.

It's just a really good intermingling of all those different organisms that just got kind of cut off from each other.

After dam removal, the man-made lakes and reservoirs drained and nearly 800 acres of land was restored alongside the river.

Wildlife sign here.

We've seen some elk.

Yeah, so all of this old little maple has been browsed, which is pretty awesome.

Kim Sager Fradkin is a biologist with the Lower Elwha Klallum Tribe.

All of this was underwater.

And so everything we're seeing here, all new growth since dam removal.

She takes us to one of the camera traps they have set up to document the animals utilizing the restored land.

Going to have a look, see what critters have been on it.

Once upon a time, it was a crazy idea to take these dams out.

The wildlife group knew that there would be a big change in the terrestrial environment once this 800 acres was dewatered.

Got some little-- something popping in there.

With the cameras out here, we're really interested in what species of wildlife are using these new restoring habitats.

Some elk on this camera.

So you can see the herd just hung out here.

They all just came through.

There's that nice foal.

We've got some deer, cougars.

When those dams first came out, this was a moonscape.

I mean, it was literally just mud and sediment and no plant life.

And so watching this suite of animals move in has been pretty incredible.

It's kind of a little bit of a "built it and they will come."

This is a neat one, because this is Moses, a nice big beautiful cat, eating the elk that he killed in the former reservoir.

Lots of snowshoe hares, snowshoe hare acrobatics.

[ chuckles ] And this one actually is extraordinarily exciting.

Do you know what this animal is?

It's a fisher, and it's got a snowshoe hare in its mouth.

[ laughs ] So, this just demonstrates that these former reservoirs are now teeming with plants and animals.

WOMAN: Oh, he didn't like the camera, huh?

The tribe's first day of fishing is going well.

[ eagle calling ] When I was younger, this river closed before I could even fish it.

So this is my first year fishing it, and got lucky first day.

[ chuckles ] The river had to restore and revitalize, and fish had to come back and they were able to go up to their traditional spawning grounds.

And, yep, just trying to teach them.

Just trying to teach the next generation and learn myself.

Oh!

Da-da... [ raven cawing ] And then having to use rod and reel, it's odd for all of us.

Traditionally, the Elwha Tribe fishes with nets.

The tribal council decided this first opening will be rod and reel.

But there's about six right here.

Yeah, see, they're all right by each other, just sitting there like this.

The tribe chose Indigenous Peoples' Day for the opening.

My son caught one, so now I've got to catch one or I'm going to hear it the rest of the day.

No.

[ laughs ] MAN: There you go!

What is it?

[ child exclaims ] RACHEL: Is that-- MAN: Ooh, it's a little jack.

I got a jack right here.

And probably weighs about, like, 4 pounds.

Here you go, Justice.

Oh, that's nasty.

This is really fun to fish on my homeland.

It feels really good, like, to finally fish here.

And I could just, like-- I live up the hill a little bit, so I could just ride my bike down here and just go fishing if I wanted.

RACHEL: Oh!

Oh, my gosh!

JUSTICE: I feel like our culture is coming back to life.

Ten years and counting since the dams came out and the river is already rebounding in remarkable ways.

This is just the beginning of what it means to once again be wild and free for the Elwha.

[ ♪♪♪ ] Out in the sagelands of eastern Washington, out near the old Hanford nuclear complex, there is a really strange building.

It stretches for miles, and I guarantee it's unlike anything you've ever seen before.

If you did see it, you'd definitely ask, "What is that thing?"

Well, producer MacGregor Campbell found the answer, and it is out of this world.

[ birds chirping ] CAMPBELL: In the shrub steppelands of eastern Washington, just down the road from one of the birthplaces of the atomic bomb, two four-kilometer-long tunnels meet at a perfect right angle.

Inside is one of the most sensitive instruments humans have ever built, meant to detect some of the most powerful events in the entire universe.

And today it's getting an upgrade.

WOMAN: You could do a ton of planning, and at the end of the day, you're kind of like, "I'll just go in there and figure it out."

Today is a "go in there and figure it out" day.

Welcome to the Laser Interferometer Gravitational-Wave Observatory, which most folks around here know as LIGO.

MAN: We bring essentially a whole new sense to the astronomy game.

We are listening to the universe where we have only seen the universe prior to now.

Telescopes look at light, but what LIGO looks for can't be seen.

When two very dense objects-- like black holes or neutron stars-- collide out in space, for a brief moment, they release more power than all of the stars in the universe combined.

This creates waves that squish and stretch space itself.

These gravitational waves spread out.

And just like sounds are harder to hear the farther away you are... By the time the energy from those huge, gigantic explosions billions of light years away get to Earth, they are incredibly weak.

The challenge is trying to create a detection system that would be able to measure such an incredibly small change in spacetime.

Which means you need a very sensitive detector.

LIGO works by shooting an infrared laser beam down the entire length of both perpendicular arms.

The beams bounce back and meet in the middle.

When a wave passes through, it changes the length of each arm differently, which throws the laser light in between just a tiny bit out of sync.

LIGO Hanford has a twin, an almost identical facility, in Livingston, Louisiana.

This allows astronomers to measure a wave twice as it passes through the Earth, helping them to understand what caused it and where it came from.

These waves are the signal of some of the most powerful events in the universe.

But for all of human history, we couldn't detect them... until 2015.

We have detected gravitational waves.

We did it!

[ all cheering ] The frequencies of the waves are in the range of human hearing.

With some computer processing and a lot of amplification, they sound like this: [ low echoing tone plays ] It goes by pretty quick.

Here it is again.

[ low echoing tone plays ] That sound, recorded early in the morning at this mysterious facility in far-flung eastern Washington, won the team a Nobel Prize in physics.

Since then, other detectors have come online in Italy and Japan, and together they've detected dozens of collisions, every one of them a tiny blip from hundreds of millions of light years away.

Measuring something so small requires incredibly precise engineering.

But the landscape around Hanford provided the right raw materials.

JEFF: The bigger you make the arms, the more sensitive you are to that change in spacetime.

Hanford is wonderful because it's flat, it's relatively easy to make four kilometers of very flat land.

Then you need one of the world's largest vacuum chambers, massive shock absorbers, and a way to control a boggling variety of mirrors, motors, and circuits.

And after all that, eastern Washington has its own special challenges.

We get these big winds here in the Tri-Cities, and 30-, 40-mile-an-hour routinely.

And it wants to pull the buildings around, and so wind for us is a direct contribution to how the machine works.

And the local wildlife.

A noise source that ended up being related to crows... [ clicks tongue ] pecking away at ice on one of the tanks that's exterior to us.

Rattlesnakes maybe have been in the building twice.

We get a lot of porcupines.

Yesterday we gave a little tour-- Oh, coyote.

Here it comes.

He's pretty healthy-looking.

He is just hanging out.

Oh, that's funny.

That's amazing.

Yeah.

Well, on cue.

Yeah, exactly.

Planned that.

Brought him with me.

[ chuckles ] Whenever you put anything on natural land, you know, things just want to come in.

For as wild as the outside can be, the inside is one of the most pristine and controlled environments on Earth.

JEFF: I would say when I first started working on the actual components of the detector, I was nervous about cleanliness.

I am a dirty person.

We are all dirty humans.

And this detector requires very clean stuff.

The most sensitive parts of the detector are kept in a vacuum off-limits to humans.

They only open the chamber every few years for maintenance and to make upgrades that they hope will let them hear more distant collisions and more of them.

It's heady stuff.

This thing right here is part of a new quantum-light squeezer.

The scientists think it will give them a clearer signal, but getting it set up will take months of precise work.

It often comes down to solving familiar problems in the moment.

BETSY: When I first started at LIGO, I thought for sure it was going to be like "Minority Report," doing all this, like, virtual stuff, and I cracked up because at the end of the day, you're like, "Did you try this one?"

Today they're trying to remove a small window that was causing some interference.

Huh!

But it won't budge.

Set screws and nuts are not my favorite thing.

It's like coal at Christmas.

Maybe we should go with plan B.

We never have a "can't do" moment.

We almost always can fix anything.

Now, let's be very careful, because the window may come flying right out.

Just remember that it's 30 pounds!

BETSY: Oh, yeah.

Okay, good.

There's thousands of parts with thousands of bolts-- all different sizes, all designed by disparate engineering teams across the entire world.

Okay, you got it?

JEFF: When you get in chamber, you have to make it work.

All right, we would've liked to have removed the whole assembly, but we're going to get to that later.

But at least now our beam is shooting straight through here.

[ birds chirping ] When we came back a year later, LIGO was listening deeper into space and hearing more collisions than ever before.

The team even detected a potential collision just hours before we arrived.

This morning at 4-something a.m. in my time zone, we had a gravitational-wave candidate come through.

It's quite high probability that it was two black holes spiraling around each other and then collapsing and merging into one final black hole.

What once won the Nobel Prize is now a weekly occurrence.

AUTOMATED VOICE: Camera A burst... MAN: Camera A burst.

JEFF: So this could be good.

JENNE: You don't want to say "boring," but it's that good kind of normal that we get really exquisite gravitational-wave candidates every three days or so.

JEFF: We're detecting event after event.

We are now a gravitational-wave factory.

But this is still a complex machine.

There's a lot of things that we can't control for.

Like if there's an earthquake in the other side of the world, everything kind of shakes out of alignment too much.

There's, like, so many problems, like, it could just be busy all the time.

And we are.

What's next for LIGO?

BETSY: Even though we just started this run, we're already planning the upgrades that will get us more range.

JENNE: Gravitational-wave astronomy is still a really new and exciting field.

It's really wonderful to be a part of something that feels kind of cataclysmic in terms of just shifting the way we think about physics.

JEFF: We really have opened up a new corner of astronomy, so, yeah, it's, uh... it's a great time to be a gravitational-wave astronomer.

[ low rumble, birds chirping ] [ ♪♪♪ ] You can now find many Oregon Field Guide stories and episodes online.

And to be part of the conversation about the outdoors and environment here in the Northwest, join us on Facebook.

[ frogs croaking ] [ birds chirping ] Major support for Oregon Field Guide is provided by... Additional support provided by... and the following... and contributing members of OPB and viewers like you.