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Holle, Champions of servant leadership, science, technology, engineering, math, all coming up right now on Alabama STEM Explorers.

Hi, welcome to Alabama STEM Explorers.

I'm Mitch, and I'm here today with Dr. Bryan Keener.

So, Dr.

Keener, where are we today?

We're at the University of West Alabama Carver Biodiversity Center.

Okay, so what is biodiversity?

Biodiversity is a term we use to assess the number of species that occur in a place.

Some places are low in biodiversity and some places are very high in biodiversity.

It's basically an overall estimate of the number of species that occur in an area.

So is it so like Alabama is algorithm about biodiverse, Alabama is very biodiverse.

Alabama is the fifth most biodiverse state in the country out of all 50 states, and it's number one east of the Mississippi River.

Alabama actually is number one in many different organisms, mainly aquatics, the turtles, crayfish, fish, snails and mussels.

So what makes Alabama so biodiverse?

Well, it turns out that this map is a great explanation of Alabama's how biodiversity.

This is a geologic map of Alabama, and it maps the different rocks that occur in the sub layers of our state.

And there's many things we can learn about this map just by looking at it.

First of all, you may notice that these bands are kind of horizontal, but things are much different up in this area.

So this marks where there was an ancient coastline here at one time.

Oh, wow.

And then there were these mountains and things were all Little Rock appears to be mangled and mashed and jumbled up.

This is caused by folding.

And Africa at one time was butting up against North America, causing all of this rock to be changed chemically and uplifted.

So this particular area is called the Piedmont.

And then we have the Ridge and Valley and the Cumberland Plateau.

And this line that marks the difference is called the fall line.

And everything below that is called the coastal plain.

Okay, that's crazy.

There's definitely a lot of different colors on here.

That's right.

Alabama perhaps has the most diverse geology in the country.

And for a state this size, it's really remarkable.

In addition to the wide diversity of rocks that we have, we have more navigable waterways than any other state.

And so those waterways mainly seen here through yellow and then up above, they're not as mapped on.

But in any case, they have cut through the rock, through millions of years, expose in many more habitats.

So each of these rocks have a different type of chemistry.

And as those rocks degrade and become soil the soils have different chemistries.

So this has created a whole array of habitats for organisms to evolve and occur.

That's crazy.

So what is a soil?

A soil This is the this is the substance that plants and other things occur in on top of rock.

Okay, that's crazy.

So how does like, how does the biodiversity change as you get farther south?

So the biodiversity changes?

It doesn't necessarily change as you go south.

It mainly changes over the different types of geologic exposures.

So Alabama as a whole is famous for different groups, as we've already mentioned, but certain areas like the Black Belt soils are more prone to grasslands.

But then in other parts of the north, it's more prone for forest and things.

That's really cool.

So is this oh, is where we are now a good place for a biodiversity center?

It's probably the best in the state.

In fact, we are located here right on the phone line.

I see a lot of colors right there, right, exactly.

And this is the very tail end of the Appalachian Mountains where the mountains meet the fall line.

And in addition to that, the most wonderful biodiverse river in the country flows right through here and crosses into the coastal plain just south of where we are.

What's that river called?

The Cahaba River.

Okay, cool.

Would you like to go see the harbor?

I love that I'd be up.

Let's go.

Okay.

Mitch, this is the Cahaba River.

Have you ever spent any time on the Harbor River?

I might have.

I don't really remember.

Yeah, well, the Cahaba River is Alabama's crown jewel of biodiversity in our state, and the biodiversity in the river has actually been maintained by never being dammed.

A lot of Alabama's rivers, they've had a lot of dams put on them, and that really has been detrimental to some of the biodiversity and the aquatic fauna.

How does that work, how to how to dance do that?

Well, you see the shoulder out here, the rifling and so forth.

It adds a lot of oxygen to the water.

And there's a certain level here.

So when you add dams, the water level goes much higher.

And the organisms that depend on that ripple and the oxygen in the water, they just can't survive in the deeper water.

So what kind of organisms they have, well, here we would find snails and fish and mussels and crayfish and turtles.

It turns out that Alabama is number one and all five of those categories in biodiversity.

That's crazy.

So are there like any species that are just that they just live here?

Yes, that's called and Endemism.

Alabama is very high in Endemism and all sorts of organisms, but there are in fish and mussels and snails to the Cahaba River cool.

The in addition to the other organisms we've talked about the flora and fauna along the Cahaba corridor is also very diverse.

All sorts of plants.

Perhaps you've heard of the famous cahaba Lily this up and down these parts of the harbor, upstream and downstream.

So how long is the Carver River?

The Cahaba River is about 190 miles long from where it began, down in its headquarters in the Sinclair County, all the way to down into the Alabama River where it joins in Dallas County.

Cool.

So can people like fish or what kind of recreational activities can you do?

There's all sorts of recreation on the Cahaba River.

It's wonderful for fishing and tubing and kayaking and canoeing.

And in fact, we see a lot of paddlers go right about here here at the at this particular show.

Cool.

So let's see, is there a lot of do you do like education and or so classes that come out here?

Right.

So here at the Harbor Biodiversity Center, we had all sorts of college students, high school students, junior high coming here and learning about Alabama biodiversity.

We have lots of habitats here on the property outside of the river.

We have caves and glades and other grasslands.

And so it's really a rich piece of property for Alabama biodiversity.

So tell me about the center.

What do you guys do at the center?

Well, we mainly focus on conservation and biodiversity education and it's a it's a new endeavor for UWA where we've been given a wonderful gift and for the sole purpose of teaching those things in biodiversity and conservation.

How long has it been around?

We received the property in 2022, January of 2022.

New brand new Cool.

So which would you like to see some of the organisms that live in the river?

Oh yeah, that'd be awesome.

I have a friend.

I have a friend of mine that came along today, Josh Millwood.

He's a zoologist.

He focuses on aquatic fauna called mussels.

And so I think we're going to try to drag a net and see what we find cool.

So now I'm with Josh, so tell me about what's in your hand.

So I have a few different species of freshwater mussels we found here.

Have two living species and shells from about seven other species and freshwater mussels are fairly common throughout the Cahaba River.

We have about 40 or 50 species found here, right?

Crazy.

Yeah, that's crazy.

So?

So those are those living.

Yes, these two are living.

So this is a species called Olympia across the dunes, also known as the elephant ear, because it looks kind of like an elephant ear.

And this is lamp seals or not.

Both of these get fairly large and are very long lived mussels.

So when you say long lived, how long would that be?

I'm not 100% sure on these two species necessarily, but both of them can live upward range, probably 60, 70, 80 years.

Oh, that's crazy.

Yeah.

We have some species that don't live that long, though.

Oh, okay.

So you said they're 40 to 50.

So what are some of those other species?

Also this other species, this is called the common name for this is called the blue fur.

It has this nice little kind of ridge on top.

This is first.

And I saw Rhino also called a pig toe based on the shape of the shell.

You can see there this one, the common name is the Alabama Orb.

And you'll notice it's got some little kind of bumps on it.

Shell.

You can't see them too well, but they are there.

And then this one, you can see it better.

Okay.

They're kind of warned by the same species.

Yes.

Okay.

So like, are they like what?

Like are they heavy?

Like the muscles, like.

Oh, yeah.

Welcome to home.

That one's really heavy.

Oh, wow.

Yeah, it depends a lot on how thick their shells are.

And some species have thicker shells than others.

And also just how much water they hold inside sometimes and how dense their tissues are.

So I've always been curious.

Mussels have always really fascinated me like, So how do they like, live?

So like, how do they like feed?

Right?

So these guys will sit down in the sediment like this.

They like to burrow a little bit and they have they'll slightly open their shell and they have these siphons that come out and that allows them to filter water in and eject other water.

And so all that water they filter in through their gills.

They use it almost like a little sieve, and they're able to collect particles that they want to eat and reject other particles.

And that's how they get their oxygen.

That's how one of the ways they reproduce and how they get their food.

So like for like 60, 70, 80 years, like some of those are they just sitting in the same spot eating stuff or do they can they move or they can move around?

Most of the time they don't move around on purpose very often, but they can if they need to, based on water levels and things like that.

A lot of times their movement is based on large storms bringing large amounts of water through and it'll actually wash them downstream.

And a lot of the species we get out here or the individuals we get out here are from that washed down.

And what kind of stuff do they eat?

Um, they mostly eat algae.

They'll eat some bacteria, but very small microscopic particles.

Okay, so like what?

Like how big would like the smallest?

Is there like any, like, like a size of a quarter.

There are some.

So actually there is a invasive species we get here.

And the biggest of those is about the size of maybe a half dollar average size of a quarter.

When these are younger, all of them start out as tiny microscopic larva.

And so at some point in time through their life stage, they are all very small, but some of them we have, some that don't get much bigger than this on their in their life and then some that will get even larger than these.

Okay.

So like, are these the kind that you would eat or you could eat them?

Probably from what I've heard, they are they don't taste very well.

They're actually accounts from the civil war of soldiers being stuck and running out of food and eating these.

And they essentially gave the sentiment that they would rather starve to death than eat any more freshwater.

Most of them have pretty bad taste.

Really that bad.

Then I have a feeling they do.

But they were eaten by Native Americans for a long for long periods of time.

So we found fossil records of that.

So like inside the shell, like, do they look like how you how they would look like when you're eating them or what they look like?

I'm kind of so they kind of have matching body types on each side.

They have a thin skin type membrane that covers the inside of the shell called the mantle.

And then within that they have a very muscular foot and that is what they can use to actually reach out.

And that helps them move, that helps them dig around.

It's a very dense muscle.

They have gills that kind of lay down in layers and then all their internal organs are kind of enclosed in all that.

And it looks kind of like a blob when you really get them open.

So like, what are the similarities between like mussels and like clams or oysters or those kind of things?

So our freshwater mussels are very similar to clams that you may find at the beach in the way they make their living.

Our mussels, what we call freshwater mussels, are technically not true mussels, true mussels in crust and stick on top of things.

Kind of like an oyster.

Clams tend to burrow what we have or not true mussels in they're technically not true clams.

Early scientists when they first started looking at these and studying these animals, just called them clams or called them mussels and clams sometimes, and mussels just kind of stuck.

So now we just call them freshwater mussels, but they similar, they burrow, they filter, feed, things like that.

So like what other type of do you have, like clams or any of that?

Any any other types of like animals like that that live in these rivers?

Yeah.

So in all of Alabama and in the Cahaba, we have another group of bivalves called starry eyed Clams.

They're in a different family.

They're more of a true clam.

They're not super closely related to these.

We have one invasive species called the Asian clam.

It's a true clam.

They're pretty common here, and that's pretty much it for bivalves.

We have a lot of snails within the harbor.

There's about probably about 30 species, 35 species of snails in the harbor.

Many of those are endemic.

We also have a lot of endangered aquatic wildlife as well.

We have a lot of fish, a lot of crayfish, a lot of mussels and a lot of snails.

So what would endanger like like an animal like this?

Because you said they don't really taste good.

And so what would so the majority of the impact on on mussels and snails and things like that or water quality.

So either water temperature getting too high or pollution flowing into the water or even too much sediment coming into the water can cloud the water up too much and can stop up their gills and things like that.

So they really need good quality water.

But these guys also serve a good purpose of helping to clean the water that they're already in.

So they're really important for other organisms in the environment, but they do need high quality habitat.

And that's one of the problems with things like dams and other things.

They slow down the water flow in most species prefer what you see out here where we have these nice riffles fairly quickly moving water that stays somewhat cool.

So do they have any predators of any kind?

Yeah.

Some things will eat them.

Raccoons and otters will break open mussels and eat them.

Actually, feral swine will occasionally feed on mussels.

They also just tend to cause a lot of habitat problems, but they will feed on them as well.

And there are possibly some fish that can eat very small, thin shelled mussels.

So something that was I was curious about was like when you're a fish in the water, have gills to breathe.

And of course, like humans or animals, they breathe through their lungs, do like mussels and need to breathe in the first place.

Or if they do, how do they They still have to breathe, just like any other living organism.

And they have internal gills, so they have sets of gills that work very similar, very similarly to the way fish gills work.

When they filter in that water, it passes over the gills and they pull oxygen out of the water.

And their gills also serve the purpose of filtering the water for their food.

That's how they find those particles.

And then for females where their gills are, it's also where they hold their babies.

And so one really cool thing about freshwater mussels and that's what I think is probably the coolest thing about freshwater mussels is the way they reproduce and the life stages that they go through.

And so in those gills, females will have eggs, they will filter in the water and those eggs will become fertilized.

For males that are upstream, typically.

And as those eggs form into larva, the females hold them inside.

And you remember that mantle tissue I told you about that kind of lines the insides of the shell.

Well, certain parts of the year when it's time for those animals to or time for those babies to essentially be born, the females, their mantle tissue inside that shell will inflate and become very dense and thick and come out of the shell and they will actually mimic the shape and colors of small fish in the stream.

It looks very much like a fish.

They'll have an eye spot on one end and they'll have different colors down their body.

One at the other end is fanned out like a tail fin and they'll sit there and twitch their tail fin and it attracts bigger fish.

The fish thinks, Oh, there's a nice prey fish I can eat.

And when it comes in to try to eat that fish, the female mussels will spray their liquid air, which is what we call the larva all over that fish.

And the reason they do that is because they have to go through a parasitic life stage at some point in their development.

So they actually clamp on to the gills of that fish and will parasitized it for anywhere between 1 to 3 or four weeks.

Does it hurt the fish?

And then eventually they fall off and they're formed into juvenile muscles there and they'll grow into adults.

So that's that's, that's amazing.

So like, it doesn't look like water or like anything could get in or out of the sea.

So they can still up pretty tight If you squeeze them a little bit, sometimes you can get a little bit of water.

These guys have had them out of the water for a little while.

So they're that's one of their defense mechanisms.

If it's too hot or there's not enough oxygen in the water or the water levels get too low, they can close up and stay really tight and lower their metabolism.

And so they don't need to use much energy.

And so they can actually survive for a while like that, as long as they don't get too hot.

How long could it really depends on the species and the weather.

If it's not too hot, they can stay out of the water.

If they stay cool, they can stay out of the water for probably up to a day or two.

And it varies between species, though some species can only live a few hours out of the water.

So do they need to live in like shallow water like this or like could they live in deeper water?

Yeah, it once again, it really depends on the species.

Some species are like really shallow water in these really fast moving currents.

Some species well, actually there are species that live in lakes that can live in lakes up to ten, 20 feet deep.

Sometimes some species like to live in the banks of rivers and they'll actually move up and down with the water as it moves throughout the day.

So it really just depends on the species.

And I think it's a good way to to highlight how how much variation there actually are in these organisms, because most people just consider them as kind of living rocks.

Yeah, like rocks.

But there's a lot of variation in how they make their living and how they live, right?

So we've looked at some mussels.

Mitch How about now we go see if we can find some other stuff you want to go see about pulling in that?

Oh, maybe we can find some fish.

Yeah.

So, Mitch, have you ever used the before?

I have not.

So these are pretty cool.

They're really good for trying to catch fish, especially in habitats we're in right now.

Essentially.

All I'm saying is, is it's a net stretch between two poles.

What really makes a science work, though, is on the bottom side of this net, there's lead weights like that.

Make sure it stays on the bottom.

And on the top there are these floats so that if you get into deeper water, it kind of holds it up.

And that way fish can't get over the top of it.

It really creates like a basket for the fish I not used until I was in college.

And so, you know, it's never too late to learn and this will be exciting.

And so what we're going to do is we're going to pull right up through here and get kind of close to the bank towards the end, probably.

And we're going to try to keep the line on the bottom of the of the river.

And we're going to see if we can't maybe get some fish or tadpoles or crayfish or something like that.

Fine.

So here we go.

And you can just kind of follow along with me here.

We want to keep a little bit of a pocket.

There you go through over that rock.

We're just going to go straight up through here.

We can go that way just a little bit towards the bank, spread this out a little wider.

And now I'm going to come in just a little bit.

And now let's raise the net up and we want to keep it pulled tight so the fish stay in it.

And we do have some fish here.

Oh, and so what we can do is if you want to hold that, I'll roll this up so that we can see what we have here and this way.

So wow, look at there are those tiny little guys.

And so we have we do have some fish here.

It looks like they're all probably the same species.

We also have a snail right there.

These look like a black tail shiner.

And so they're called black tail shiners because of that black dot.

They're right in the back of the tail fin.

Oh, yeah.

And you can put you can see they're called shiners because they're very shiny.

Right.

They are.

We have many species of shiners right here in the harbor and some of them are hard to ID, honestly, but this one is usually one that's very abundant and pretty easy to to to find.

Well, it looks like we have shiners, the one snail, a lot of leaves.

Sometimes.

If we look through some of these leaves, though, we can find really cool aquatic insects and insect larva.

I'm not seeing anything right now, but I am seeing at least 2 to 3 species of snail right here.

I'm not a snail guy, so I can't necessarily tell you exactly what these are.

But I do know that we have around 30 to 35 species of snail just in the harbor alone, and about 13 of those are actually endemic to the harbor, so they're not found anywhere else.

That's cool putting.

Let's let's try again.

Let's keep going up through here and we'll see if we can find something else.

We just.

Just like any fishing, you got to find where the fish are, all right?

And you can kind of stop.

And I'm going to come toward you.

We're going to come in just a little bit and pull up right here.

Look at some more of the same.

We had one and it jumped out and it was also a black tail.

There's some one under that.

Right?

Okay.

So we have one here.

Let me see if I can get to the rock.

Probably the same things.

Yeah, there's a couple right there and then it up here.

Yep.

This is the same the black tail shiner.

They're really common species.

That's what we catch a lot when we're saying there are other shiner species though, and some darter species as well.

They really like this habitat.

They're just a little harder to catch.

The black tail shiners are so abundant and just really easy to catch.

So we didn't get any other fish.

Mitch But the ones we did catch, we have a thing called a viewer, which is just kind of a small little like aquarium.

Essentially, we can put them in so we can see them a little better.

Do you want to go maybe check those out and see if we can really look at those?

Right.

Awesome.

So this is our viewer, Mitch.

And all this is essentially is a tiny portable aquarium.

And so we can put the fish, we get in there and they don't have quite as much room to move around so we can really look at them better.

And so we have our few Black Tail shiner We got plenty of those, but we also end up getting to small bluegill and so bluegill, you know, people often think of catching those in the lake, right?

But they're very common in the rivers.

They kind of tend to hang towards the slower areas, but sometimes the smaller ones do get these riffles.

And so these are both young bluegill here.

As I kind of mentioned to you earlier, we have multiple species of shiner in the harbor.

We also have a lot of small darters which are kind of a bottom drying fish.

They're harder to catch, unfortunately.

So we didn't get one of those today.

But I'm really excited that we got the bluegill to see a little bit of diversity in this represents a tiny fraction of those 100 and roughly 130 species that are found within the Cahaba River in general.

Yeah, and neither of these are endemic.

They're both found all over the place.

They're very common species, obviously.

So do these guys get bigger?

Yeah.

Those bluegill get, you know, average size is probably close to the size of my hand.

Even bigger.

I've got some bigger ones than that.

And these are just one species of sunfish that we have.

We have about four or five pretty common species of sunfish we can find in the Cahaba Okay, cool.

So, Mitch, do you do you have any other questions about the fish or about some of the other things we've seen out here today?

Well, these guys, it looks like there's a lot of them around here.

Yeah.

These black tail shiners are extremely common, and they're a really important part of the food chain here.

So you can tell they're pretty small.

We have different sizes.

We have some really small ones down here.

We have some much larger ones up here, but they don't really get much bigger.

A really big one would probably be about maybe three inches long, but they're extremely important food source for many of the other fish species out here.

These bluegill, as they get bigger, they will actually likely feed on some of these shiners as well, along with raccoons, otters, a lot of other aquatic animals.

So do like any type of other type of like aquatic mammals live around here.

As far as fully aquatic mammals are, what we consider a fully aquatic mammal around here is really just otters for the most part.

We also have muskrats here as well.

Those are probably our two main aquatic.

We have an invasive species that I don't think is really like a harbor much, but it's called a nutria.

Yeah, it's similar to a muskrat as well.

And we do have beavers.

So I was wrong when I said the otter was really the only one.

We actually have a lot of aquatic mammals and then a lot of mammals that utilize the aquatic areas as well, such as raccoons, weasels, even some of our other carnivorous type animals will come down.

So bobcats, coyotes, things like that.

They will come down and look for food along the river as well.

Yeah.

So what makes the Cahaba River so biodiverse?

Well, one of the things, as we heard earlier from Dr.

Keener, it's a it's a pretty long stretch of river, and it does have the longest stretch of unnamed river in the state at about 140 miles of the river.

One of the big reasons it's so diverse, though, is it passes through three different physio graphic regions within the state, and so it passes through the Appalachian Plateau areas, it passes through the region valley and then it eventually gets into the coastal plain.

And so all that difference and variation in geology allows for a lot of different small habitats to form throughout the river, and it really allows for a large amount of different species to come through.

And so the Cahaba is able between between where it's at and just the general habitat and geology of Alabama, it allows it to have a lot of species, but it is also a highly impacted river.

It runs through a lot of high populated and heavily urbanized areas where there's a lot of pollution, a lot of runoff.

And so it's really a river that we need to all work hard as citizens of the state to try to preserve as well.

Well, thank you so much for showing me all this today.

It's been such a pleasure to see all of these cool animals and learn all of this new information.

Yeah, I'm glad you had a good time and come back any time.

And maybe we can find some more cool stuff to show you.

Yeah, that'd be awesome.

Awesome.

Thanks, Mitch.

I'll see you next week on Alabama STEM explores.

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