Beaver Dams Nina and the Neurons

# If you've got a question and you don't know where to go

# Ask Nina for some help Cos she's got a science show

# She makes sense of her senses While helping all her fans

# By doing her experiments with potions and with bangs

-# Touch your tongue

-Tongue

-# Fingers

-Fingers

-# Eyes

-Eyes

-Ears

-Ears

-# Nose

-Nose

# Nina and the Neurons find out what you need to know

# Nina and the Neurons find out what you need to know

# Luke, he helps us with our eyes, and Felix with our touch

# Ollie sniffs out smells and scents, and Belle, she hears so much

# Bud is Ollie's brother he helps us with our taste

# They're Nina's little Neurons and they're coming to your place

-# Touch your tongue

-Tongue

-# Fingers

-Fingers

-# Eyes

-Eyes

-Ears

-Ears

-# Nose

-Nose

# Nina and the Neurons find out what you need to know

-# Yeah!

-Nina and the Neurons find out what you need to know

# Oh, yeah! #

NINA HUMS TUNE

Oh, hello there.

How odd - I've turned the tap off but I can still hear running water.

Oh, no, my bucket's got a leak in it.

I'll need to find something to block the hole.

-Hmm.

-BEEPING

Oh. I hear a beep, I see a flash, I wonder what they're going to ask.

BEEPING STOPS

ALL: Hi, Nina!

-Hi.

-We've got a question for you.

-Why do beavers build dams?

Oh, that's a great question. Why do beavers build dams?

Now, a dam is something that stops the water in a stream.

But why do beavers build them?

Why don't you come down to my workshop and we'll investigate?

-ALL: See you soon, Nina, bye!

-Bye.

Well, I'm going to need some help to answer this one,

and I know just who to ask.

OK, Neurons, time to get to work!

ALL: Neurons at the ready, Nina!

OK, today's question is why do beavers build dams?

Which Neuron do you think will be most useful

in helping us find the answer?

It's Belle.

CHEERING

CHANTING: Go, Belle! Go, Belle! Go, Belle!

Brilliant! I'm all ears, Nina.

Today's question is why do beavers build dams?

Beavers build dams on splashy, noisy streams,

so Belle will be helping me today, but stand by, Neurons,

I've a feeling I may need help from all of you.

Right, I need to get the workshop ready

before the Experimenters arrive.

Bethan likes swimming. Rhianna loves drawing. Corey likes playing golf.

But they all want to know - why do beavers build dams?

So today, for one day only, Bethan, Rhianna and Corey become...

the Experimenters!

-Hi, guys.

-ALL: Hi, Nina.

Welcome to my workshop and thank you for your great question.

Why do beavers build dams?

Well, first, let's have a look at some beavers in action.

LUKE: Wow, would you look at those beavers? They're so busy.

-BELLE:

-And listen to the beautiful sound of the stream.

BELLE GASPS

-What are the beavers doing?

-Carrying sticks.

Yeah, and they're carrying them in their mouths.

-BUD:

-Eugh! Twigs wouldn't taste too good!

-What do you think they're doing with them?

-Building a dam?

Yes, beavers are the only animals to build dams,

and they build them in streams

and use lots of materials that they find nearby to make them strong.

Let's do an experiment to find out what dams do.

ALL: Whoo-whoo! An experiment! We're ready, Nina.

So, we are going to make a dam.

I'm going to make the pretend stream using this watering can,

and you guys are going to build the dam using those sandbags.

-Are you ready?

-ALL: Yeah!

Here comes the stream - go, go, go!

NINA GIGGLES

That's it.

That's good.

Squash them together, squash them right up.

Excellent.

Fantastic job. So, what happened to my stream?

-The sandbags got in the way.

-Yes, they slowed the stream right down.

-And what happened to the water?

-It made a puddle.

Yes, it made a little pool here.

So dams slow down the flow of water in a stream.

The water builds up and creates a pool that wasn't there before.

Of course it's not just beavers that build dams.

That's right, Felix, people build dams too. Have a look at this.

This dam is built by people,

and it's so big that it's created a lake behind it called a reservoir.

And reservoirs store water for people to drink.

LUKE: So beavers make dams in streams.

-BELLE:

-The dam slows down the stream and makes a pool.

BELLE LAUGHS

Why do beavers make a pool?

That's a great question.

I think we need to go somewhere very wet to find out more.

Oh, goody, I love this bit. I wonder where Nina is taking us.

Nina said somewhere wet, where could that be?

-BUD:

-Maybe a paddling pool, or the seaside!

-I can hear water, ha-ha.

-And I can see trees.

Looks like we've arrived!

So, you asked, "Why do beavers build dams?",

and so far we've found out that beavers build dams in streams

and the dam makes a pool, but now we want to know why they make a pool.

So we've come to this forest where some clever beavers

live in the wild.

Wow! Are we going to see a real-life beaver?

Sorry, Bud, beavers are actually very shy, and they usually

only come out at night, so we might not see one today.

But we will see something amazing that they've built.

-Have a look at these. Do you see these marks?

-Yeah.

Yes, well, these are teeth marks from where

the beaver's been gnawing at the tree.

-NINA GIGGLES

-Have a look at this.

Beavers eat bark and leaves,

and they also use the branches to build with, so they can

nibble away at a tree with their very strong teeth

until it falls over.

NINA LAUGHS

-Now, what do you think this is?!

-Oh, a beaver dam.

Yes! It's a dam that the beavers built.

LUKE: Wow, look at the big pool they've made.

-Do beavers live in the dam?

-That's a great question, Rhianna.

Actually, no, they don't. They build themselves a home called a lodge.

They build it in the pool so the doorway is under water,

to keep them safe from predators.

They must be very strong to carry all those logs and branches!

Beavers are very strong, Belle,

and they have a very clever way of moving big branches about.

So I think we need to do another experiment to find out more.

Now, beavers collect branches and store them in their lodge.

And we have two tree branches here

and we're going to try and move them.

They're about the same size and weight,

and Corey and Bethan, you guys are going to go together and try

and move your piece of wood along the water.

You and I are going to go together, Rhianna,

and we're going to move it along the ground.

-So, everyone, pick up your piece of rope. Are you ready?

-ALL: Yeah!

-Go!

NINA GASPS

Okey doke. Now, what do we think was easier?

-Moving the branch along the water or the ground?

-Water.

Yes, wood floats, so beavers move branches in the water because

it's much easier than dragging them along the ground with their mouths.

OLLIE: So beavers build their dam to make a pool.

-BELLE:

-So it's easier for them to move branches around.

-Well remembered, Neurons.

-How do they build the dam, Nina?

That's a great question.

I think we need to do one final experiment to find out.

Your question was, "Why do beavers build dams?"

And so far we've found out that beavers build dams to make pools,

and they float branches on the pools

because it's the easiest way to move them.

But now we want to know HOW they build their dams.

-So, do you think we can build a dam like the beavers?

-ALL: Yeah!

Yes, I think can we too.

So we're going to build a dam across this stream.

But remember - you should never play near water without an adult.

Beavers start by building a strong base,

and they would use heavy materials like big branches.

-So, shall we give it a go?

-ALL: Yes!

OK, whoo-hoo!

Oh, oh...

NINA SIGHS

Yeah, let's get them nice and close together, really good.

OK, so more big branches I think.

NINA GRUNTS

Oh, that's lovely. This is great teamwork, guys,

and do you know, beavers work in teams just like this.

-Do Neurons work in a team too?

-OTHERS: Yes, Bud!

Now we need some smaller branches.

Ah, that's good.

Great dam-building, Experimenters!

So we put the big pieces of wood down first,

and then smaller branches next.

And look, the branches are slowing the stream down.

It's still letting water through.

-BELLE:

-I can hear water trickling through the gaps, Nina, ha-ha!

You're right, the dam still has lots of holes in it,

letting the water through, but that's the same with beaver dams.

Can you guess what they use to block the holes?

-Mud.

-FELIX: Not mud, Nina,

it's all cold and squidgy - ugh!

Yes, the beavers get mud from the banks of the stream

with their paws, and then they pat it onto the dam to block any holes.

And they listen to the dam, and if they can hear a trickling sound,

they know there are still some holes to be blocked.

-BELLE:

-Beavers have very good hearing, listening out for all

the leaks in the dam and filling them out with mud.

Beavers' dams usually let a trickle of water through,

that helps keep the pool nice and fresh.

Come on, guys, let's take the dam down.

You should always leave the countryside the way you found it.

# Nina and the Neurons! #

So, your question was,

"Why do beavers build dams?" And I think we've answered it.

LUKE: We learnt that beavers build dams with wood to make a pool.

-FELIX:

-They build their lodge in the pool to keep them safe.

-OLLIE:

-They use the pool to float and move branches.

BELLE: Beavers block the holes in the dam with mud,

then they listen to see if their dam has any leaks.

-So, I hope that's answered your question.

-ALL: Thanks, Nina, bye!

You're welcome, bye.

If you want to know more about the science that's all around us,

go to the Nina section on the CBeebies website.

Have fun!

# Super structures

# Super structures

# Super structures, super structures, super structures!

# Some of them are tall, some of them are wide

# They're bumpy, lumpy, wiggly too

# Wiggly too!

# Some of them are strong, some of them are small

# Like me!

# They're windy, whirly, wishy too

# All around... #

Look over here!

# Build it, stack it, pile it up

# Come on, let's get building

# Building, building

# Race it, hold it, make it stick

# Come on, let's get building

# Come on, let's get building

# Some of them are cosy-warm, some of them are chilly... #

Brrr!

# Keep us safe and hide us too

# Hide us too!

# Some of them are just for fun or help us to stay dry

# They're underground and high up too

# Look around! Over here!

# Build it, stack it, pile it up

# Come on, let's get building

-# Building!

-Building!

-Building!

# Race it, hold it, make it stick

# Come on, let's get building

# Come on, let's get building! #

And remember, there are superstructures everywhere.

Whether they're big or small, wide or tall, we can all get building.

See you again soon, bye!

ALL: Bye!

Get building!