Saving white sturgeon

The Kootenai River, which crisscrosses the U.S. Canada border is home to the endangered white sturgeon. In order to help save the sturgeon the Kootenai tribe of Idaho is undertaking a massive habitat restoration project.

TRANSCRIPT

The Kootenai River, which crisscrosses the U.S.-Canada border, is home to the endangered white sturgeon and is in need of attention.

Now the Kootenai Tribe of Idaho is undertaking a massive habitat restoration project.

The tribe is teaming up with U.S. Geological Survey researchers and using acoustic monitoring equipment to figure out how much sediment is in the river and how to reshape the river to help the sturgeon.

Our environmental reporting partner EarthFix has the story.

Movement is a river's constant, always flowing, always going somewhere.

One of the biggest things that it meant to the tribe was it was kind of like a highway, and they traveled up and down the Kootenai River to get from one place to another.

And they moved around from area to area for hunting and fishing and gathering purposes.

[ Train whistle blows ]

The Kootenai Tribe lives along the Kootenai River.

They follow a covenant handed down by their ancestors.

We have created the Kootenai people to look after this beautiful land.

As long as you do that, all your needs will be met.

To this day, we've kind of honored that covenant, you know, and I guess that drives us forward.

White sturgeon are sacred to the Kootenai.

They're also endangered.

Only about 1,000 wild sturgeon are left in this stretch of the river.

The tribe is trying to increase that number.

U.S. Geological Survey is helping them by listening to the water.

Acoustic Doppler meters are installed on the side of the river, aiming across the flow.

They send sound waves through the water.

When those waves return to the meter, they sound different.

That's because of particles in the water.

I'm really excited about this concept and this technology.

This is sort of a new concept for monitoring sediment nationwide.

We collect sediment samples while that equipment is running so that we can actually send that to the lab, and it correlates with that returned signal.

And so there's a lot of analysis on what we do with our collections and then corresponding to that power signal that returns back.

Right now, across the nation, we've got about 40 sites, roughly, where we're implementing this kind of acoustic technology to try to estimate sediment.

The more material you've got in the water, so the more sediment you've got in the water, the stronger that reflection of the sound will be in the water.

So the instruments can measure that, and we can use that information to try to relate that to sediment concentration.

Every river has sediment.

It's the sand, gravel, and the general muck that rolls along with the current.

The issue with sediment in the Kootenai River is that it's interesting.

It's both good and bad for the system.

It's good in that sediment moving through a river can promote natural changes in the movement and formation of a river, but on the other hand, too much of it can impact a habitat.

And for the sturgeon, for example, it's covering up a lot of the eggs that they're laying as part of their spawning effort.

Too much sediment suffocates spawn.

Researchers monitor sediment by placing sticky mats in sturgeon-spawning beds.

The mats collect hundreds of eggs.

The eggs are so adhesive.

Rolling down the river, they adhere right to the mat, and we pull them up.

And just we call it reading the mat, and we go over it with a fine-tooth comb and look for eggs.

As you can see, there's plenty of sand stuck to them.

The Kootenai River's sediment load in Idaho has changed over decades.

In some places, there's too much sediment.

In other places, there's none.

That's due, in large part, to a hydroelectric dam.

The Kootenai River starts and ends in Canada.

It runs 485 miles with about a third of those miles dipping into Idaho and Montana.

Much of the river's water in the U.S. is held behind the 400-foot-tall, 3,000-foot-wide Libby Dam in Montana.

Idaho's 66-mile stretch of the Kootenai is downstream of that, which means those river miles are controlled by humans rather than nature.

We see this everywhere in the U.S., where changes are made to an environmental system in response to the biggest issue at the time, and that's, you know, no one person's fault.

It's just our human response to natural hazards and natural conditions, and so that's the reality of where we're at.

Decades of holding back water changed the watershed.

And when you have an alteration to the flow and the sediment transport, the river takes on a different character, and a lot of the natural hydrology is altered.

So one of the things that happens when you don't allow... In this case, the river is no longer allowed to kind of go out into the floodplain and kind of promote some natural changes and side channels and little points where the fish can hide and rest as they're moving upstream.

That's been one factor that has influenced the survival of the sturgeon.

The dam was built in 1975.

The white sturgeon population plummeted after that, putting the ancient fish on the endangered species list in 1994.

When the sturgeon went onto the endangered species list, there really wasn't any program that was, you know, being put into place, so we stepped in, says, 'Well, why don't we do something?'

That's where listening, rather than looking, comes in.

Researchers are working with the tribe and state and federal agencies to create an underwater map of the river for restoration work.

Having these instruments out there has really been a benefit to us to see what's going on all the time.

Without the acoustic meters, we'd have to just get up there and collect a sample when we could and when it was safe to do so.

Now that we have these instruments in there, we can see what's going on.

We can better target and time our sample collection.

It really gives us a more complete and more accurate picture of what's going on in the Kootenai River, in terms of sediment.

With that clearer picture, they'll be able to sculpt river channels to help fish.

Because sturgeon numbers are so low, researchers are also mapping spawning beds, so they can catch spawners and raise their eggs in a hatchery.

We have to move with the fish, figure out where they're at on any given day to hit those periods when they are active and they're actively feeding.

It certainly brightens everybody's spirits when we catch fish, bring it in, and it's a good fish for the program.

Just to bring a healthy, wild adult, you know, it's a fish that big that's still in the river, is pretty cool.

Yeah, it's the highlight of, probably, everybody's job.

The hope is all this hatchery work goes away once the river is restored.

The long-term goal is not to have a hatchery program.

It is for the fish to be able to find the appropriate habitat, survive through all their life stages, and self-propagate.

Sturgeon are the slow-growing, long-living giants of the water world.

It will be decades before recovery success is evident, but any jump in the population is worth listening for.