OutSCIder Classroom
Saguaro National Park
Episode 102 | 27m 27sVideo has Closed Captions
Explore a cactus forest to learn how plants and animals adapt to the desert in Saguaro National Park
Hike through the cactus forests of Saguaro National Park to learn how plants and animals adapt to the dry, ot conditions of the Sonoran Desert. Learn why you don't want to mess with a gila monster and how to take care of succulents at home.
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OutSCIder Classroom is presented by your local public television station.
Major funding is provided by the National Geographic Foundation
OutSCIder Classroom
Saguaro National Park
Episode 102 | 27m 27sVideo has Closed Captions
Hike through the cactus forests of Saguaro National Park to learn how plants and animals adapt to the dry, ot conditions of the Sonoran Desert. Learn why you don't want to mess with a gila monster and how to take care of succulents at home.
Problems playing video? | Closed Captioning Feedback
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My name is Chris Anderson, and I'm at Saguaro National Park, home to the largest cacti in the United States, the giant saguaro.
But these aren't the only living things that call this park home.
There are dozens of species of cacti, bushes and trees, as well as mountain lions, javelin as and gila monsters.
So how are all these living things able to survive in a hot, dry location like the Sonoran Desert?
Let's find out today on OutSCider Classroom.
[Intro music] Ahh.
There's nothing quite like walking through a cactus forest.
The titular character of this park, the saguaro cactus, can grow over 50ft tall.
But how does a plant that big survive in the Sonoran Desert?
A place that gets less than 12 inches of rain in the entire year, and for where the average daily high can be over 100 degrees for months at a time.
One of the Saguaros best adaptations, it's also its most obvious, these spines.
As you can see, these spines are super sharp.
They can get a three inches long.
Any animal who'd want to take a bite out of a saguaro would need some special adaptations, otherwise they could get seriously hurt.
These spines could puncture deep.
And if they break off in your skin, they could leave some nasty splinters.
Yikes.
The saguaro is covered in these spines, which make a really good deterrent against would be diners.
But that's not the only adaptation these cacti have.
To learn more how these giants thrive out here, let's hop over to the Desert Botanical Garden.
Hi, my name's Marie Long.
I'm the director of education at the Desert Botanical Garden in Phoenix, Arizona.
So my favorite adaptation about the Saguaro is if you look at the Saguaro really closely, it looks like an accordion.
[Accordian playing] Throughout the year, they expand and contract.
And so when they're nice and plump and fat, that means that they have a lot of water.
And then, like an accordion, they can shrink when they lose water.
It's pretty neat little thing.
We actually can see the Saguaros small and big throughout the year.
I'm actually, believe it or not.
Oh my gosh, I'm standing on Saguaro roots right now.
The Saguaro roots are so small they're only about four inches underneath the surface.
And if you see how tall these Saguaro cactus, up to 40ft, their roots actually will go out, 40ft out.
And they only have a very short taproot.
I mean, it's hard to imagine how that saguaro cactus can even stand up because it's so big.
Saguaro National Park is home to 1500 different plant species.
That's a lot of biodiversity for a place that doesn't get much rain.
So how can all these plants exist in such a dry environment?
Part of the reason is the range of elevation.
Here we're about 2600ft above sea level, but at its highest point, the parks around 9000ft above sea level.
That range makes for a wide variety of microclimates, with temperatures getting cooler as you go up the mountains.
Here in the valley.
You'll find cacti like the Saguaro, the Barrel, the Prickly Pear, and you'll find bushes like Creosote, the Palo Verde and Mesquite, who have extensive root systems to access water deep in the soil.
Further up, you'll find Cottonwoods and Oaks, trees you might expect to find in a forest in the eastern part of the country, but not next to a desert up here it's cooler and wetter.
The perfect climate for these trees.
And even further up you'll find pine trees.
Up here it stays cold enough that snow covers the ground most of the winter.
Perfect for these guys.
All these plants are able to coexist because they've adapted to their part of the mountains.
Think about it.
The cacti would be way too cold at the higher elevations.
And the pine trees would all dry out down here in the valley.
Scientists call this resource partitioning, where species avoid competing with one another by adapting to different environments.
Think about a bowl of assorted candy.
One person will eat the ones with Rice Krispies.
Another personal eat the kind with peanuts inside.
I'll eat all the dark chocolate candies because I can't help myself.
Don't judge me.
Anyways.
Everyone gets their favorite type of candy without competing with one another.
Unless you take my dark chocolate.
But of course, plants aren't the only things that call saguaro home.
This park is home to lots of different animals with their own adaptations for surviving in the desert.
And to help us understand some of that is Ranger Camp.
So Ranger Camp, what kind of animals live in Saguaro?
Whoo hoo a lot.
We have all sorts of mammals.
We have insects, birds, reptiles, even a couple of amphibians that live in the area sometimes.
In fact, we are the bee capital of the nation.
The hummingbird and the ant capital of the nation.
With how many species we have.
An example is we have over 700 species of bees within a 100 mile radius of Tucson.
So this is a lot of biodiversity for a place that really doesn't get that much rain.
It doesn't.
No, the whole city of Tucson averages around ten inches of rainfall annually.
Wow.
So how are these animals able to survive in an environment that doesn't get that much rain?
It gets quite hot during the day.
What kind of adaptations do they have?
So there's a lot of animals out here that have adapted to be able to eat the cactus.
Whereas we cannot, you know, the prickly pear cactus we can eat and there's a couple of other ones.
But in general, like the Saguaro, the barrel cactus.
Western movies have lied to us.
You can't get water anything out of them inside is very acidic.
You get a lot of stomach issues.
Obviously, the needles would get in the way a lot of times.
Whereas javelina and mule deer and some of the some of the rodents, they just go right up to it and chew on it.
You'll even see sometimes javelina with spines still sticking out but the saliva will end up just kind of disintegrating them, and they'll fall off.
Wow.
Another really great adaptation that I love is the kangaroo rat.
They don't have to ingest any liquid water at all.
Sometimes they'll take seeds and nuts, and they'll bury them underground, and the humidity will get absorbed into them.
In addition, their metabolism is able to almost pull oxygen and hydrogens off of what they eat and combine it into water in their own system.
So they can just create water in their in their bodies.
Yeah.
Yeah.
To a small degree, of course.
It's not all of it.
They do get some from the seeds and nuts, but they also retain all that moisture.
So if you go up to like a glass or a mirror and you breathe on it, but the little heart thing, you know, all that stuff that doesn't happen with them.
Some scientists are doing research.
They put them up against glass, and they don't have any moisture that comes out of their breath.
So you wouldn't like on a cold morning, you wouldn't see, like, mist in their breath?
Nope.
Not at all.
Yeah.
Wow.
So these, these animals are really good at finding moisture, but, like, retaining it inside their bodies.
That's really cool.
What about some other animals that live in the park?
Well, Desert Tortoise is another one that's really able to retain that moisture.
They're able to store a lot of urine and stuff in their bladder, which that can be held for six months or more sometimes.
Man.
Holding your pee for six months.
Exactly.
Yikes.
Which is one of the reasons we like to tell people.
If you see one, crossing the road, just stop.
Don't try and help it across.
If you pick it up or stress it out at all, one of its first defense mechanisms is to urinate on whatever is attacking it, even though you're trying to help it.
And that can be detrimental in the middle of the summer.
If it loses all that moisture, it's probably not gonna find any.
Oh, my.
So we say just, you know, keep your distance.
Stop the car.
Let across.
Even if it goes slow.
[Music] It may not seem like it, but the Saguaro is a flowering plant.
Yeah.
These guys flower April through June.
You can see these beautiful white flowers that open up for local pollinators.
The nectar provides wildlife like hummingbirds and bees, a tasty, sugary treat.
And the pollinators help the saguaro reproduce.
Later in the year, the cactus produces a juicy red fruit that have been enjoyed by wildlife and humans for thousands of years.
When the fruit gets eaten, the seeds get dispersed.
[Music] Hi.
My name is Cam Juarez.
I am the community engagement outreach coordinator at Saguaro National Park.
[Woosh, pops] [Ding] My primary role is really just to, engage the park with the community and the community with the park.
A lot of National Park Service folks tend to be transient, so they don't have deep roots in the community a lot of time.
So I'm that, that, that, that middle man, if you will, in, in those, in those kinds of conversations.
So a lot of times it's getting, you know, the introduction between some of the local elected officials or, or even state and national officials.
I was born to a migrant family.
And we, we traveled back and forth between California and Arizona, following agricultural crops.
My, my parents, that's all they did their entire life.
So as my mom was pregnant with me, you know, in California, she was exposed to an herbicide, along with a lot of other workers.
Crop duster, you know, accidentally dumped its load, you know, in a field full of workers.
And my mom was pretty sick during my second, third trimester, and I was born, and, it was it was difficult at first because, I have a pretty, pretty bad, heart defect that, you know, relied that I relied on on a lot of different heart surgeries.
I'm a pacemaker patient, so I, you know, I'm robotic.
You know, you got the Wi-Fi going and my pacemaker, so it's kind of cool, but, but, you know, learning about that when I was in high school and in college, becoming a community activist, understanding that it was herbicides, you know, pesticides that caused my physical disability and my heart defect.
So environmental stuff that impacts people.
While most people think of Edward Abbey and stuff like that and think about, you know, these beautiful landscapes, sometimes I think about how environment impacts community.
If they come out here, inevitably they're going to fall in love with this place, especially if you if you come here early in the morning as the sun is rising, or in the evening as the sun is setting, and you get to engage with wildlife, and, you know, the flora and fauna is beautiful around those times of the day, they fall in love with this place.
And anybody that's ever fallen in love knows, once you fall in love, you want to protect those things.
And that's really what conservation is about for me.
It's a cool thing to be a park ranger, and it's even a cooler thing to be a dad of a kid who loves national parks.
And, you know, he talks, you know, articulately about, being in nature because of his dad, because his dad is a park ranger.
So it's kind of cool to have the admiration of the child.
Here there's not a lot of signal, and there's not a lot of opportunity for devices.
And you just heighten when you hear the crunch of, of the rock underneath your shoes and you, you hear the birds singing, you know, during the summer, you hear the cicadas, and you just feel, you know, especially right before the monsoons, you smell and you feel the rain's about to hit, you know, and, and we tell a kid, you know, that smell that you hear that you smell and you're like, oh, it's going to rain.
You know, you're you don't have, like, ancient Native American knowledge.
It's this plant.
And I walk a kid over and I say, keep your hands around this plant and then exhale, you know, your breath onto the plant and cup your hands and then smell and the look on their face.
Any kid, I don't care what kid it is, I don't care how much money their parents make or don't make, you know, they cup their hands around that flower and they blow and they smell rain and they're like, oh my God.
It's like the galaxy exploded in their brain, you know?
And like, they make that connection and and instantly in love with this desert.
And then the hike changes completely.
It's no more complaining.
It's just what's next?
What are we going to learn now?
[Music] The desert's full of monsters!
Now, you might be saying to yourself, Chris, monsters aren't real.
And, well, technically you would be correct.
Monsters aren't a real thing.
But gila monsters are.
They are real and they are cool.
And I cannot wait to learn more.
So while I am not an expert in gila monsters, I have a friend who does know a thing or two and that is Ranger Jordan Camp.
So Ranger Jordan, what can you tell us about these little guys?
Gila monsters are awesome.
There's a lot I could tell you about.
Topically, they are one of the first social distancers.
A lot of people ask me about them, you know?
Where can I find them?
Why don't I see them?
They're very elusive.
They spend about 95% of their life underground.
As far as we understand.
They really only come up to the surface to eat, maybe check some stuff out, but then they go back underground.
And considering that they only eat an average of about ten times a year.
That's it?
That's about it.
Yeah.
And sometimes they can go an entire year without eating.
You may not notice they've got a chunky little tail in the back that doesn't drop off like most lizards.
It's kind of like carrying around a kitchen pantry with you, which is great.
They can just pull the reserves from that in times of stress or the winter.
And so they're very robust in that way.
So if I do see a gila monster in the wild, how do I know that it's a gila monster?
How do I identify these guys?
It's a great question.
First of all, they have a really bright orange and black colorations, which is perfect for Halloween time.
And they're about, you know, yay big when they're adults, so.
Oh wow.
So they're quite massive.
They're a pretty big lizard.
You'll also notice they have almost looks like beads everywhere.
Little bumps.
That's why they're called a beaded lizard.
And what those are called osteoderms, which you might be familiar with, with crocodiles and alligators and other things that have bones in their skin.
So bones in their skin?
Yeah, it's part of the skin.
Whereas the difference is on a gila monster from them is that those osteoderms are actually fused to the skull.
So if the skin is removed or if they're dead, you actually still see those bumps all over the skull.
Now, are those to protect the gila monsters from predators?
Indeed.
Yep.
Plus they look really cool.
They do look cool!
And then another interesting part about identification is that each one can be ID'd specifically, kind of like a thumbprint.
If you ever take a picture, especially from the top, the beads and the little black and orange dots are different for every single one of them.
Wow.
Yeah.
So we heard a little bit about these gila monsters potentially being venomous.
Is that true?
They are the only venomous lizard in the United States.
Wow.
Are they dangerous to people?
The description of the pain is as if you had lava flowing through your veins.
Yikes.
So it's not the best thing to do.
I definitely wouldn't get too close to them.
It'll put you in a hospital, and it's not going to feel great.
However, unlike a snake or something that injects its venom with fangs, the venom is actually just part of the saliva in the lower jaw, and they have a crazy bite and it'll just grab on.
They got a bunch of little teeth, and they'll just kind of go back and forth and chew, and you just you can't get them off.
You know, there are some tools to use it, but generally the only way to get them off is by submerging your hand under, or whatever part that got bit, underwater completely, and they let go.
So that's where the trouble comes in.
So if you do see a gila monster, take a picture, but definitely keep your keep your distance.
Yep.
Social distance.
Even when the pandemic is over.
Social distance from gila monsters.
I can do that.
Due to habitat loss, gila monsters have become a threatened species.
We humans keep building on the land they call home.
To study how the gila monster population is changing, Saguaro National Park, in partnership with the University of Arizona, started a citizen science project that lets anyone help collect data on these little lizards.
Yeah, you can be a scientist.
If you see a gila monster, take its picture on your phone and email it to the park.
Just remember, don't get close and certainly don't touch these animals.
They don't move very fast, but they are venomous and that venom packs a punch that can certainly land you in the hospital.
Your pictures give scientists important information on gila monster populations, since the patterns on their tail are unique to each individual gila monster, just like your fingerprints are unique to you, researchers can learn a lot about how gila monsters live, where they move, and other important information about the population.
It's super easy.
Now, if you'll excuse me, I've got some more monsters to document.
[Music] Cacti are part of a special group of plants called succulents, who have a waxy coating on their leaves to help them store water.
These plants could be a really cool addition to your back yard, and to give us some hot tips on how to grow them are my friends Jeremy and Jamil.
Hi, I'm Jeremy and I'm Jamil, and we're the black botanists.
Today we're inviting you to join us in our garden as we explore some of the amazing succulents we've got growing.
There's over 25 families of succulents, and in those families, there are thousands of unique species.
These hardy plants grow in some of the world's most extreme environments.
In this crate, we've created a mini desert environment complete with sandy soil and a variety of different succulents.
You'll notice that most of these have thick, green leaves that are pretty different than your average leaf.
Instead of wide, flat leaves like what you might find in a tree, succulents tend to have these thick, green leaves that allow them to store lots of water for long periods of time.
Let's take a look at this succulent.
This right here is a jade plant native to South Africa where there's a long, dry season.
Many succulents evolved in areas with low rainfall and high heat.
This required them to develop an ability to store water and even prevent evaporation.
So Jamil, what's the difference between a cactus and a succulent?
Great question, Jeremy.
For that answer, we have to look for areoles.
Some succulents evolved to have large stems with small prickly spines.
Those prickly spines grow spots called areoles.
Take a look at this peanut cactus here, which is native to Argentina.
Instead of thick leaves, this one has thick stems that allow the plant to store energy.
The areoles have long spines or hairs, that grow out of them, which help protect the plant from any unwanted visitors and also provide shade.
Succulents are a great plant to grow because they're tough.
They've evolved to be able to handle long periods without water and grow in some of the most barren soil on this planet.
With that in mind, it's important to remember that succulents only like be watered when the soil is completely dry.
They've got all the water they need stored right in their leaves.
They're also really easy to propagate, which means that you can turn one plant into many.
First, take a cutting or leaf from an existing succulent.
The next thing we want to do is leave our cuttings out in the sun for a few days.
This will allow the ends to callus and will prevent them from rotting once we plant them in the soil.
Next, we'll want to make sure that the soil stays lightly moist and make sure it gets lots of sunlight.
Within a few weeks, we'll have roots just like the ones on this succulent in no time.
There's actually lots of succulent plants that are native to North America, including places that aren't even deserts.
Some succulents are very cold tolerant.
In fact, where I live in Ohio, there's the eastern prickly pear, which is native and thrives in sandy soils.
As I always say, if you could plant native then plant native!
Cactuses also make for great house plants.
Just remember to take care of your plants and don't lose them in your house.
We all lose in a cactus surprise.
[Boink] "Ouch" [Music] My name is Lina Perez-Angel, and I'm a paleoclimatologist.
[Woosh, pops] [Ding] So a paleoclimatologist studies how climate has changed through the geologic past.
So between hundreds to 100 thousands to millions of years ago.
So I particularly do tropical paleoclimates.
So I'm interested in warm periods of time during the year.
And actually those warm period times have been mostly defined in high latitudes.
So the first things like I go to the field, I go back to the tropics, which I am from.
And then I go and collect the rocks and also lake sediments for from cores that you can get from drilling lakes.
So you collect those samples in order to analyze in the lab.
I discovered science like a little bit late in my life, I was halfway through my majoring as an engineer, and I took a class like a B class in, kind of geosciences 101, and I discovered the rocks are really cool and shiny.
And in general, how the Earth system works and how you can study that and the different relationships between animals and atmosphere and rocks in the past.
Being non-native English speaker was extremely challenging to access a lot of the knowledge in science because most of the material is in English.
So I needed to learn English in order to learn, you know, geology and those things.
I was always really bad at English when I was in high school and those things.
But I think, the university provided free classes.
So I was able to in my extra time, you know, a lot of people have hobbies, I went to study English in order to obtain those levels in English.
And believe it or not, a lot of times you have to see it with a paper and a dictionary next to it, and you start reading and then looking for those words.
So that's and then practice.
That's how it happens.
I think one important thing is that, geology can tell us a lot that we don't know by being detectives of the earth.
So the thing, we can go and, have samples and, you know, different hints and clues that can tell us how our earth has changed in the past.
And that is really significant in terms of what we can expect for the future.
So as I'm interested in a warm period of time in the past, I want to know what's going to happen in where people like where my family is, is it going to rain A lot?
Is going to be a drought?
So I think geology is really cool because it's like a portal to the past.
[Music] So we're here with Brian Wolf from the backpacking shop Roads, Rivers and Trails.
And we're going to learn about the what you absolutely need to do while you're on the trail.
So, Brian, what do I need to know when I'm going for a hike?
Yeah.
Thank you.
You know, first we just like to outline a few of the Leave No Trace principles.
And one of the first things is pack it out.
Pack it out?
Yep.
Absolutely.
Anything that you take in, on the trail you're responsible for bringing back out.
Well, that's so, so any sort of gear or maybe any trash or anything, I make sure I bring out with me.
Yep.
Trash is the big one.
Just forgotten things.
Just be really present and aware of what you're bringing in so that you're not leaving a footprint.
You know, when you leave.
Okay, well, what else do I need to know?
So the second thing is, don't take any souvenirs.
So just like we're not leaving anything behind, we don't want to take anything that's going to hurt the next person's experience.
So rocks, flowers.
It's very pretty for you.
And leave that for the next person to enjoy as well.
So it's really all about like, making sure everyone else's experience is just as great as yours.
Exactly.
You nailed it.
Okay, well, if I'm on the trail, is there anything I should know, like etiquette wise, with other hikers?
Yep.
Good point.
You're on the trail.
So staying on the trail is another principle that we want to consider.
We don't want to widen our footprint.
And so we want to stay on the trail when it's appropriate.
Most places are going to have marked trails.
Okay.
And I'm sure if you get off trail then that might disturb habitat or maybe damage some wildlife.
Absolutely.
And you know, there's some places that are more sensitive than you'd think and take longer to vegetate and things like that.
So it is important to just stay on trail to keep that experience for everybody.
What about interacting with other hikers?
Is there some etiquette or, you know, maybe some, some rules I should know?
Absolutely.
You know, I mean, one, it's considerate to give right of way to the uphill hiker.
You know, as they're trekking up and using a lot of energy, I usually step aside for them.
But in general, we just want to be respectful of everybody else's time in the outdoors, and what they're doing.
So that could come to cell phone usage or music on the trail.
Think of the experience that everyone else wants to have and make sure that you're not interrupting it.
Well, I can definitely remember those Leave No Trace principles when I'm outdoors.
If you want to learn more great ways that you can protect nature while you're out exploring, check out the Leave No Trace website, LNT.org, where you'll find great resources and ways that you can get involved in protecting parks near you.
Happy hiking!
If you visit Saguaro, get an early start to your day.
Temperatures can get really hot, especially in the summer.
Carry lots of water, sun protection, extra snacks, and stay on the trail.
The soil is filled with bacteria and fungi that help the plants grow and you don't want to step on them.
And check the local fire restrictions, forest fires can start and get out of hand really quickly, and you don't want to be that person who burns down an entire national park just because you had to have a s'more.
Besides, I think s'mores are kind of nasty anyways.
[Music] Major funding is provided by the National Geographic Foundation Want to learn more about our national parks?
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