Jane: Hi everyone! It's me, Jane. But Why is celebrating a
huge milestone this week, we are turning 10. Our first episode
was published on April 1, 2016 so much has happened since then,
we've followed your curiosity through the world and met with
so many wonderful guests and learned so much about well,
everything. Some of the kids who sent us questions 10 years ago
are in college now, and some of you listening today probably
weren't even born yet. To celebrate this special
milestone, we thought it would be fun to bring back our very
first episode. So that's what we're going to listen to today.
See if you can hear any changes in how we made the show back
then and how we make it now.
This is But Why, a podcast for curious kids from Vermont Public
Radio. I'm Jane Lindholm, your host. Today on the show, we've
got owls and turtles and bears. Oh my! It's all about animals.
This is our very first episode. So I want to tell you what, but
why is all about. It's a show led by you. You ask questions,
and we find someone who can give you an answer, and that way all
the rest of us listening get to learn something cool. It's a
big, interesting world out there, and there is a lot to
learn. There's plenty to scratch your head about, like, why is
the sky blue? Or how do they get the graphite inside the wood in
a pencil? So if you have a question that you want some help
answering, let us know. To send us a question ask an adult,
maybe a parent to help you record it. Your adult can record
you asking your question on a smart phone using the memo app,
and then send it to questions@butwhykids.org we have
all the instructions at butwhykids.org. We want your
first name and where you live and what your question is.
Our question this week comes from a friend of mine. His name
is Finn. He lives in Hinesburg, Vermont, and he's four years
old.
Finn: How do bears sleep all winter?
Jane: Did you hear that? Finn wants to know how bears sleep
all winter. Now there are actually eight different species
of bears, and not all of them do sleep during the winter. The
polar bear, for example, is very active in the wintertime,
although females do build a little den and spend a few
months in it when they have babies or cubs. But in Vermont,
where Finn lives, there's only one type of bear, the North
American black bear, and it usually does hibernate or sleep
all winter long. So I turned Finn's question over to someone
who knows a lot about animals and nature in Vermont.
Mary Holland: I'm Mary Holland. I write natural history books,
and I spend much of my time outdoors looking for things to
write about and photograph. Black bears do sleep all winter,
and they do so because they can sort of shut their bodies down
before they go to sleep. In late summer, they go on an eating
binge, and they eat and eat and eat lots and lots of plants and
fruits and insects, and they get fatter and fatter and fatter.
Sometimes they even double their weight. So a bear weighing 200
pounds would weigh 400 pounds, possibly, and then when they get
all big and fat, they find a den to sleep in. And sometimes the
den is under a root, or sometimes it's in the snow,
under a broken branch, or sometimes they even sleep right
out in the open under some evergreen trees. But what they
do is, they slow down their body and their hearts beat much, much
slower than when they were active. And then they also
breathe much less frequently. They take a breath every 45
seconds, or almost every minute, which is much slower than they
normally breathe in the summer, and they go into hibernation.
Jane: So what Mary's saying is, the bears get really fat, so
their bodies have enough energy to allow them to sleep all
winter, and they slow their breathing down. It's a way to
survive through several months of cold, harsh weather when
there's not enough food outside to eat, sleeping all winter is
what is meant by hibernation.
Mary Holland: People didn't used to consider bears hibernators,
because their temperature only drops about 10 degrees. It's
roughly from about 100 degrees Fahrenheit to down to about 88
Degrees Fahrenheit, about 12 degrees, actually. And
scientists, biologists, used to think that your temperature had
to drop way, way down in order to be called a hibernator, but
they've since decided that bears are hibernators, and you can be
a hibernator even if your temperature doesn't drop very,
very low. So once they go into hibernation, they don't eat,
they don't drink, they don't pee, and they don't poop, and
they're in hibernation for four to five months, sometimes even
longer. And what they have is they have a plug, actually, in
their butt that keeps them from going to the bathroom. And when
they wake up in the spring, in April and come out of their den,
the plug comes out naturally, and they start eating again.
Jane: So does anything happen to bears in winter, or do they just
sleep?
Mary Holland: While they're sleeping, they are using up
their fat, and those cells break down and provide them with water
and calories, and they also break down some of their muscle
and organ tissues, and those turn into proteins to keep the
bear alive. Female black bears actually give birth in January
to tiny, little cubs, anywhere from two to five of them,
usually, and they are actually not completely asleep. Their
sleep is quite shallow, so that when the baby cubs need to
nurse, then the mother wakes up and arranges herself so that
they can get her milk. And then when the baby cubs nap, the
mother naps. It's very much like people.
Jane: And so the babies, how big are they when they're born?
Mary Holland: They weigh about half a pound, and they're
roughly seven inches long.
Jane: They're tiny!
Mary Holland: Very tiny, very tiny.
Jane: So when they come out of hibernation in April, though,
the cubs are much bigger, are they able to feed themselves,
and they have the bear fur that everybody thinks of a bear as
looking like?
Mary Holland: They're not completely weaned.
Jane: I'm going to stop Mary right there for just a second.
Weaned means a baby has stopped getting milk from its mother. So
when the bears come out of their dens and Mary says they're not
fully weaned, it means they're still getting some of their food
from their mother's milk.
Mary Holland: They look like a miniature adult. They can walk
and climb. They're very agile, and they are starting to eat
solid food. Usually it's some of the green vegetation that comes
up earliest in the spring, often by ponds.
Jane: Mary, do you think the bears dream while they're
hibernating? I mean, I would dream if I was asleep for that
long.
Mary Holland: I would too. I think I would be, yes, I would
be dreaming about the coming summer and turning over logs and
finding all kinds of ants to eat. That's what I'd be dreaming
about.
Jane: Black bears usually sleep for four or five months, in
places like Vermont, where the winters are cold and dark, in
Alaska and northern Canada, they'll sometimes hibernate for
six months or even more. But in some places where it's warmer
and there's food throughout the winter, like Mexico, black bears
will barely hibernate at all. When the bears wake up, they
have one mission, to gain weight, so they spend most of
their time eating, eating, eating. At the beginning of the
spring, they look for green plants to eat, but over time, as
trees and plants start to blossom, they find nuts and
berries, and if they're lucky, things like honey or fish. They
can also get a taste, though, for human garbage and bird seed.
So if you share your habitat with bears, you should try to
keep your trash cans away from them, and you might want to
think about putting away your bird feeder during the spring,
summer and fall months, so the bears can't get at them. By the
way, I mentioned there were eight types of bears. Some of
them hibernate, like the black bear we've been talking about.
Brown bears also hibernate. And if you've ever heard of a
grizzly bear, a grizzly bear is a subspecies of brown bear, so
it's a type of brown bear. The other species are polar bears,
panda bears, sun bears, sloth bears, Andean bears, which are
sometimes called spectacled bears, and the Asiatic black
bear, which is also called a moon bear. And just so we're
clear, the koala bear is not a bear, it's what is called a
marsupial.
Mary, bears aren't the only animals that hibernate for the
winter. Can you talk about a few other kinds of animals?
Mary Holland: There are other animals, such as bats and
woodchucks that hibernate with the woodchuck, it has a very
similar response as black bears. They stuff themselves at the end
of the summer. If you have a vegetable garden, you're well
aware that woodchucks visit it frequently at the end of the
summer. And they put on lots of lots of weight, about a third of
their body weight they put on. And then they leave their summer
burrow and head to the woods for their winter burrow. And then
they curl up and they go to sleep and enter a very deep
hibernation. Their body temperature dropped much lower
than black bears, so they're in a much deeper sleep. Black bears
can waken up quite readily when they're sleeping. Whereas a
woodchuck, if you were to dig into a woodchuck burrow where it
was hibernating and lift it up, it wouldn't move. It would look
as though it was dead. Its temperature drops from about 97
degrees, which is roughly what a black bear's is. But whereas a
black bear only drops down to 88 degrees Fahrenheit, woodchucks
are about 47, 46, 47 degrees Fahrenheit, so they're just
hovering above freezing.
Jane: So that would be like what it feels like inside your
refrigerator.
Mary Holland: Exactly, exactly, and they stay in that state.
Well, we have February is the month of Groundhog Day, but in
Vermont, at least woodchucks are fast asleep on February 2, and
it's probably another month or month and a half before the
males wake up, and then they come out of their burrows, and
they look for a female burrow and a female to mate with. And
then after they mate, the female goes back to sleep, and the male
trots back to his burrow, and he goes back to sleep for a few
weeks.
Jane: What about some amphibians? They have
interesting ways of hibernation.
Mary Holland: I'm sorry. I was thinking of just mammals, frogs
and turtles, reptiles and amphibians both hibernate. The
reason for hibernation is because there's a lack of food.
Frogs, basically, a lot of people think they bury
themselves in the mud. They don't. Aquatic frogs, frogs that
live in a pond or go down to the bottom of a pond and just sort
of lay on top of the mud, because they breathe through
their skin, and they need to be exposed to the water to get the
oxygen in the water into their skin. But they are not for the
most part, they're not active. Turtles, on the other hand, do
bury themselves in mud, like a snapping turtle, an aquatic
turtle or a painted turtle, will bury themselves in mud and shut
down their body even further so that they need very little
oxygen, and they remain there until spring as well.
Jane: One of the other really interesting animals that I
learned about hibernating just recently is what a lot of us
know as the wooly bear caterpillar. So it's that
caterpillar that's pretty fuzzy, and it's black and orange, and
usually it's black on both ends and orange in the middle, or
orange, sort of rusty red. And people often say you can tell
how harsh the winter is going to be, because the more orange, the
milder the winter it's going to be. So if you see a wooly bear
that's very orange, in theory, we're going to have a warm
winter, and it's not going to have too much snow or cold.
Mary Holland: Do you want to know the real truth?
Jane: Yes.
Mary Holland: The amount of orange is simply a reflection of
how many times the caterpillar has molted.
Jane: Molting means shedding the skin. It's how some animals grow
bigger. They shed their outer skin, and they grow into a new
skin or a new shell, depending on what kind of animal it is,
one that's a little bit roomier.
Mary Holland: Each time it molds. There's an additional
section of orange, so.
Jane: So the orange ones are the older they're the elder wooly
bears.
Mary Holland: Yes, the more orange, the older, the longer
the growing period has been. So if we have an early spring or a
late fall, it's able to feed longer, and therefore probably
have more orange.
Jane: Mary, I also read that these caterpillars have an
interesting thing that goes into their bloodstream that's kind of
like anti freeze that you put in your car so they can hibernate
and they just freeze solid.
Mary Holland: Yes, a lot of insects have sort of glucose
substance. It's just like anti freeze, and that's how they can
survive. They're not warm blooded, so they don't try to
stay warm, and they can't but they have this, you named it
antifreeze in them, that keeps their cells from freezing,
Jane: And it's called a cryoprotectant.
Mary Holland: Yes, exactly. It's interesting. You mentioned the
wooly bear, because wooly bears are one of the few moths that
overwinter as a larva, not in a cocoon as a pupa, and not as an
egg, but as a caterpillar or larva, and they don't turn into
a moth until the spring. So in the spring, you'll be seeing
really ragged looking, wooly bears crawling around before
they form their cocoon and emerge as moths.
Jane: And the type of moth they turn into is called an Isabella
Tiger Moth. Do you know what that looks like?
Mary Holland: It's, I'm afraid it's quite dull. It's a tannish
brown, nondescript little moth, maybe an inch wing spread.
Jane: That was naturalist Mary Holland telling us why bears
sleep all winter and about some of the other animals that
hibernate. If you want to learn more about animals in nature,
check out Mary's book. It's called Naturally Curious, and it
tells about what's happening in nature in the New England
region, in every month of the year.
Do you recognize that call that's a barred owl. Sometimes
people say their call sounds like "Who cooks for you, who
cooks for you all?"
If you live in the eastern half of the United States or Canada,
or in the Pacific Northwest and parts of western Canada, you may
have been able to hear one of these elusive creatures. But
have you ever seen a barred owl up close? They're pretty cool to
see in the wild, flying almost silently through the woods at
dawn or dusk. Some lucky kids recently got to meet a barred
owl named Chapin, and we paid a visit too. Chapin was seriously
injured several years ago and can't live in the wild anymore,
but she was rescued, and she's now taken care of by an
organization called outreach for Earth Stewardship. She lives in
an aviary that's like a really big bird cage. Chapin is pretty
quiet when she's visiting with human friends. When we got to
meet her, she was sitting calmly on a leather glove worn by Craig
Newman, and Craig told us a little bit about Chapin and what
it's like to take care of a wild animal like this.
Craig Newman: She was injured when she was hit by a car in
2006 and she's been with us since then. She is very
distinctive in that she has dark colored eyes. They're dark
brown, the only owl that we have here in Vermont that does have
dark eyes. The rest have light green, greenish yellow, or some
light color like that. So. And she also has vertical dark bars
on her chest that the name is derived from, the barred owl.
And she has a sort of a nice, round earless head. She has no
ear tufts, feather tufts. They live outside in a large aviary,
and she actually has two roommates. They're all barred
owls. Yes, we don't mix species, because somebody might be
breakfast for another bird, if we were to put them together.
Well, for me, it's a lot of fun. Of course, it's a lot of work, a
lot of cleaning, a lot of feeding, maintaining their
habitat. She mostly eats mice and small rats. Wild living
barred owls eat a variety of different food, especially
summertime. They eat lots of amphibians and songbirds, mice.
But in captivity, she mainly gets mammals. We've had some
other owls that we've had for over 20 years. This time of
year, there, once the sun goes down, there's quite a barred owl
party, because we have wild living barred owls that live
nearby, and there's lots of conversations going on, so it's
pretty noisy.
Jane: Can you imagine what an owl party would be like? It
might sound something like this.
That's a pair of barred owls calling with their nestling,
their little baby owl, and here's what it sounds like when
two pairs of owls are calling back and forth.
What they're communicating to each other is something along
the lines of, this is my space or my tree. Buzz off. You can't
live here too.
The sounds you've been hearing of the barred owls calling were
given to us to use by the Macaulay L:ibrary at the Cornell
Lab of Ornithology.
They have a pretty cool website if you're interested in hearing
more bird calls of all kinds, and the website will tell you a
lot about where birds live and what their behavior is, what
things they eat and what they look like. We have a link up at
but why kids.org .Thank you so much for listening back to our
first ever episode of But Why. Thanks to all of you for
listening for 10 years and to our wonderful guests who have
shared your curiosity and their expertise with us. But Why is
produced by Sarah Baik, Melody Bodette, and me, Jane Lindholm
at Vermont Public and distributed by PRX. Our video
producer is Joey Palumbo, and our theme music is by Luke
Reynolds. If you like our show, please have your adults help you
give us a thumbs up or a review on whatever podcast platform you
use, it helps other kids and families find us. We'll be back
in two weeks with really an all new episode. Until then, stay
curious.