WEBVTT

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In the lonely houses in a faraway forest

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the secret lives of ghost\'s
haunt a Canadian scientist.

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Hello operator it\'s YJ39336

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I\'m registered White Horse 7559.

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I would like 841-4242 please.

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Thanks operator. Hello Marriott\'s Liz Hofer
calling from the other end of the lake.

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For a weather forecast it\'s
blowing in starting to lift here.

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What\'s happening? Boreas god

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of the north wind rules here.

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And everyone in the boreal
forest obeys his command.

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Liz Hofer will stay home for now.

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While outside in the dreaming snow escaped
the magic of the sleeping northern forest

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Seems to spring to life in the Tufte did
fantastical creature Liz seeks to know.

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This is the lynx.

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Wildcat fabled jumper solitary carnivore
with eyes of legendary sharpness.

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Once known as the wood ghost

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this consummate stalker is now
itself under constant surveillance

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Hello I\'m David Suzuki.

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Welcome to the nature of things.

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Most of us don\'t pay any attention to the
network of trails left in the snow by animals.

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We rarely see.

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Tonight will experience the
compelling and mysterious dance

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of the tracker and the tract will follow in

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the footsteps of a tireless
biologist in the remote parts of

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the largest remaining forest on the
planet Canada\'s boreal forest.

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She\'s on a quest to
understand the lifecycle and

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the interconnections between the
elusive links and the snowshoe hare

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As a predator biologist Liz has spent

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years studying the boreal forest
and the creatures caught in it\'s

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delicate WEB at the heart of
which sits the snowshoe hare

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central to its ecology and
favorite dish of the hungry links.

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Yet this herbivore hold
sway over the lynxes fate.

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Prey and predator partners in a
mysterious dance of death and renewal.

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Aboriginal hunters noticed at first
this strange cyclical dance.

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Later it crops up in nineteenth-century
records of the Hudson\'s Bay Company.

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And it continues still performed
against the backdrop of

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the boreal landscape which
covers 1 third of Canada.

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Liz haul furs dumping ground lies near
the Kluane National Park in the Yukon.

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The hair is quick ears alerted to danger.

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Sensitive hearing pitted against

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the lynxes keen site able to spot
at 300 meters it\'s dish of choice.

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The old adage first catch
your hair still applies.

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The sad fact is links love the taste of hair
and given the chance would eat nothing else.

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But despite powerful legs
their maximum speed is

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30 kilometers per hour
to the hairs agile 50

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Still those same legs can cover
four meters in a single bound.

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A sudden spring from a hidden ambush may
accomplish what speed alone cannot.

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The successful links

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Tramples that chosen spot to spread its
hair and consumes it slowly leaving

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only the stomach pause and fur on
the snows once pristine tablecloth.

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The private dining habits
of the fastidious links add

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to the dossier Liz has compiled
on this secret of animal.

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A field technician she\'s
grown expert in collecting

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data on carnivores Through the
age old practice of tracking

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It\'s pretty simple but elegant
as a technique for learning

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what animals do by observation of the
sign that they leave in the snow.

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It\'s one of the really quite
neat features of winter that you

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get this tool that requires
a lot of labor and

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time but is very simple

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and ensure and gives you a lot of data
that you can\'t retrieve any other way.

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By tracking we mean that we are
following step first step.

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What that animal did.

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We follow exactly where the
animal went from the moment.

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We pick it up until the end of the day.

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Basically. The idea is that
you would get a long record

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The exact activity of

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an individual animal the signs are
there you just have to read them.

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Liz hopes the signs will lead to

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a clearer understanding of the
cycle binding hair and links.

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A 10-year cycle occurring in boreal
forests across the continent.

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At roughly the same time.

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1998 was the last time hare populations
peaked with up to four hairs per hectare.

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Three years later they were
down to one every 25 hectares

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Harris can have three to four
liters a year at the peak of

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the cycle causing numbers too sore by 300%.

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Their solitude is broken when the brief boreal
spring allows the mating games to begin.

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One year after hair numbers plunged
their main predator began to disappear.

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Many starved to death others set off
in search of better hunting grounds.

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Relaxed in its vigilance that link steps
lightly synchronously in the snow

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The links feet are very particular
it\'s one of its adaptations

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to to the world that it
occupies for the size

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of the animal the front feet
out very big surface area and

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that surface area is covered with very
very dense for also looking at those feet.

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The hind feet are very big
and broad and on top of

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that for the overall size of its
body the links is really light.

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Those features make the links able to
walk and deal with very heavy snow.

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The fate of the links in
the system here no matter

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what part of the hair cycle it was
born in its fate is largely tied to

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the state of the heared population
and how many hairs there

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are determines basically how well

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any given links is going to do
over the course of its lifetime.

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When it\'s high of the cycle things
are pretty straightforward.

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When there are a lot of hairs out there.
Things are good.

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Life is simple for everyone.

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Everybody eats a lot of hairs.

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When the numbers of hairs are low very low

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Life becomes a lot more interesting
and it\'s more difficult to

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understand the interactions
of the characters at the low.

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This low is much lower than the last
low by almost 50% in the hair numbers.

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Appearing only every ten years
the law allows biologists like

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Liz the chance to trace what happens
when populations melt away.

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As winter deepens and hunger haunts

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the forest hairs become mere dreams
in the mind of a starving links

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Ravens are creatures of
myth in some cultures

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Omens of bad luck and death
in others of Providence.

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In this case they\'re excited calls our
music to the ears of a famished links

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alerting it to the frozen carcass of a
wolf already half eaten by other wolves

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Ordinarily they would stick up their
nose and just keep right on walking.

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But when times are tough links
have to eat whatever is around.

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You can see right away that
links are not not as well

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adapted to feeding that way but they
sometimes are forced to eat them.

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And when they do they are
at a great disadvantage

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because coming across any
kind of carrion or carcass in

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winter which is when most of
the kills or made the meat is

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frozen lynx doesn\'t have a way
of dealing with frozen meat.

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It\'s why it prefers to hunt.

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And it\'s it\'s very First of all fussy
about what it eats and how it eats it

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And all of those things are are not suited
to eating large chunks of frozen meat.

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Consider the clause there
retractable as cats are and

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they\'re they\'re very fine and they\'re
meant to reach out and grab a hair.

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They\'re not meant for digging into

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hard frozen flesh to get down at at
some meat that you can actually chew

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the canines are are quite
fine and not meant for for

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heavy chewing and ripping

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because of that they just can\'t
get at the frozen meat very well.

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They have to really hold and pull
and struggled to get it there.

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They may even use their tongue to soften
up corners of the exposed frozen meat

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little bit by little bit
to soften it up to be

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able to grab without breaking their
teeth and then chew it very slowly.

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So it\'s a lot of work for the links

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In winter Harris browse on Birch and

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willow twigs which are never
thicker than five millimeters.

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Even food hidden by snow is easy to find.

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Since hairs have a strong sense of smell.

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Unlike the links.

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Hungry or not every links gets drowsy.

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Just like the family cat.

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It likes to settle down for
a nap several times a day

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Those toughs that stick up above the
ears are very particular to the links.

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And it doesn\'t have these big huge
years that a dog has but it has

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quite a good ear and then these tuffs are
extremely sensitive as its whiskers are

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to even a slightest breeze of wind and
that helps it not only to hear better but

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also to keep in mind the direction
of the wind when it goes to

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choose the site for its ambush position.

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A links even a very large mail
links weighs about 16 kilos.

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That\'s not very much for
an animal that size

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It\'s just the general large
frame and that wonderful long

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dense further that makes the animal
look a lot heavier than it actually is.

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But it\'s really quite light on its feet.

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The story of the links and the hair is
best read printed on parchment of snow.

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Aboriginal trackers believed in a sympathetic
bond between a beast and it\'s prints.

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And that a trace of the spirit
of every animal remains behind

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transient clues to a timeless track
worn by all living creatures

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In this land of the Northern
Lights dawn and dusk

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our favorite browsing times for the Hare

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whose winter coat makes it almost
invisible against the snow.

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Most of its predators
including the links are

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colorblind seeing only
shades of light and dark.

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One more hungry day dawns for the
watcher who is also being watched.

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Another fine couponing morning and it
is the 22nd of February minus ten days.

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Since last snowfall is one and I will be
tracking backtracking on a single linked.

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List has been tracking links since 1986
starting with a close Johnny project.

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A 10-year study involving
three Canadian universities.

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It was designed to investigate the
complexities of the boreal forest

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Liz\'s aim is to track the
links over the course of

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its day while making sure not to be seen.

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The links won\'t older it\'s routine as
long as it\'s unaware of her surveillance.

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If you start out on a fresh
links track that we know as say

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only one day or if we walk
forward on the track we

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will catch up to the links most likely
they walk very slowly at a rate of about

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a kilometer and our that took us quite a

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while to figure out but we
did it quite precisely.

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And they also take very many naps.

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By the time you get out there and
winter you\'re quite good shapes.

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You can walk at quite a rate.

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You could easily bump into them then
of course your record for that day is

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destroyed because the the behavior of the
animal changes then it\'s no longer natural.

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Step number 816 this links has
made an ambush bed. Number two.

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It\'s overlooking an active squirrel mitten.

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It Spice encrusted there is no attempt

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and the habitat is to
spruce immature occur.

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Here we have the links coming in
sizing up the situation and making

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that approach behind this hump of snow
overlooking an active squirrel min.

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So in this case the once the links fig

00:19:52.730 --> 00:19:55.819
got it\'s positioned correctly
it\'s just going to stay there

00:19:55.820 --> 00:19:58.069
long enough to be able to get

00:19:58.070 --> 00:20:01.759
a chance to nab that squirrel as it
goes from the tree back and forth.

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In this case it\'s stayed there long enough
to make a real ice crust on that snow.

00:20:07.340 --> 00:20:08.989
So it stayed there

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Crouch down and actually melted into

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the snow a bit so transferred some of its
heat to the snow to make that crust.

00:20:17.180 --> 00:20:23.479
It\'ll it\'ll stay there until it either
gets something or has to move on.

00:20:23.480 --> 00:20:24.859
And and that\'s what happened in this case.

00:20:24.860 --> 00:20:29.029
It didn\'t actually make an attempt as you can
see it it got up from that bed and kept on.

00:20:29.030 --> 00:20:33.439
But if there had been a squirrel
it would\'ve left out of it from

00:20:33.440 --> 00:20:35.569
that that hard encrusted
area would have given it

00:20:35.570 --> 00:20:38.749
a platform to leap up
and grab the squirrel.

00:20:38.750 --> 00:20:44.629
Squirrel not thinking about the links at all
wouldn\'t even see it if it were looking

00:20:44.630 --> 00:20:47.539
because from the school\'s point of
view there wouldn\'t even be much

00:20:47.540 --> 00:20:50.824
showing up that links as it came
down that tree over to this cache.

00:20:50.825 --> 00:20:55.879
All it could possibly see or just
the tips of the year toughs That

00:20:55.880 --> 00:21:01.534
would be visible above that little hump of
snow behind which the links is crouched.

00:21:01.535 --> 00:21:05.569
This links we\'ll spend
quite a lot of time with

00:21:05.570 --> 00:21:10.069
this type of strategy hunting out of a
bed like this in this type of situation.

00:21:10.070 --> 00:21:12.829
In this case it ran out of time or

00:21:12.830 --> 00:21:17.100
patient and carried on walking
with no attempt out up here.

00:21:18.910 --> 00:21:22.969
Print by print step-by-step

00:21:22.970 --> 00:21:27.379
Liz follows in the opposite
direction to which the tracks lead.

00:21:27.380 --> 00:21:31.230
Measuring the distance
traveled is she does so

00:21:32.560 --> 00:21:37.309
We follow the track exactly and click off

00:21:37.310 --> 00:21:41.989
steps at our own pace which we then
translate back into a real distance

00:21:41.990 --> 00:21:47.449
that that animal covered in between the things
that we are noting that it did activity

00:21:47.450 --> 00:21:55.450
wise to stay alive a links needs to eat a
hair every day but these are desperate days.

00:22:27.760 --> 00:22:32.404
This is an attempt made by this links

00:22:32.405 --> 00:22:36.844
A hair it\'s unsuccessful after 32 liters.

00:22:36.845 --> 00:22:38.974
That\'s the 30-second leap there.

00:22:38.975 --> 00:22:43.980
And it\'s in habitat that
is three spruce immature.

00:22:49.750 --> 00:22:53.374
32 weeks is a lot of energy to put out.

00:22:53.375 --> 00:22:56.539
And that\'s what she did
unsuccessfully in this case.

00:22:56.540 --> 00:22:58.999
So at this point of the
cycle for her to take

00:22:59.000 --> 00:23:04.084
that much energy and tried to catch a
hare and not get 1x is is a big day.

00:23:04.085 --> 00:23:08.010
We hope that later on in the day
she\'s going to find something else.

00:23:09.010 --> 00:23:14.344
With all their watchfulness wrote
naturalist earn a seat and Thompson

00:23:14.345 --> 00:23:19.129
They must pass many winter days
with hardly a scrap of food.

00:23:19.130 --> 00:23:23.730
The predator has become starvation spray.

00:23:32.980 --> 00:23:38.794
The skills Liz has honed our
skills we once lived by.

00:23:38.795 --> 00:23:43.249
Once when we were all hunters
and gatherers we two followed

00:23:43.250 --> 00:23:46.339
an animal\'s tracks paying
acute attention to

00:23:46.340 --> 00:23:51.150
the natural world because
our survival depended on it

00:23:58.980 --> 00:24:03.294
But what Liz Huns today is knowledge.

00:24:03.295 --> 00:24:07.059
Her careful research and
that of others should throw

00:24:07.060 --> 00:24:12.740
new light on the interdependence of
all creatures in the boreal forests.

00:24:16.140 --> 00:24:23.454
I was very lucky in that I grew up in them
in places where I could spend a lot of time

00:24:23.455 --> 00:24:26.559
with my family and with
friends doing things

00:24:26.560 --> 00:24:29.964
in the in the woods and on the
rivers and in the mountain.

00:24:29.965 --> 00:24:36.500
So pi was lucky that way and have
always done it myself on my own

00:24:43.870 --> 00:24:48.409
To the snowshoe hare with
its luxurious fur coat

00:24:48.410 --> 00:24:53.430
anything down to minus 30
seems like room temperature.

00:24:53.830 --> 00:25:01.470
Lower than that it feels chivalry enough to
seek shelter under a neighboring spruce.

00:25:14.890 --> 00:25:21.829
Years spent tracking links have given
Liz and insight into their behavior

00:25:21.830 --> 00:25:25.489
Step 81806 this thunks has

00:25:25.490 --> 00:25:30.064
a long bed number two long bed snugged
up against the tree there and

00:25:30.065 --> 00:25:34.339
the habitat is to Poplar mature

00:25:34.340 --> 00:25:40.020
mixed with seeing how the cold can
make even a predator vulnerable.

00:25:40.510 --> 00:25:44.569
It takes calories for
the links to stay here.

00:25:44.570 --> 00:25:48.709
It loses some of its body heat to
the snow and it\'s a trade off.

00:25:48.710 --> 00:25:54.499
It can spend some time here to rest
on speculation that it might also

00:25:54.500 --> 00:25:57.319
get a meal but if it waits too long and it

00:25:57.320 --> 00:26:00.289
doesn\'t get a meal then it
loses a lot of calories.

00:26:00.290 --> 00:26:01.834
Therefore it could lose weight.

00:26:01.835 --> 00:26:04.504
It\'s got to always balance
those two things.

00:26:04.505 --> 00:26:08.089
And when there\'s lots of hairs
it doesn\'t take the links

00:26:08.090 --> 00:26:12.559
much energy to plop down basically anywhere
he walks doesn\'t walk for very long.

00:26:12.560 --> 00:26:16.009
It just finds a nice situation and takes

00:26:16.010 --> 00:26:19.969
the gamble that by taking a rest there
it\'s gonna get a meal as a reward but

00:26:19.970 --> 00:26:23.389
if there aren\'t very many hairs around
then he can spend a lot of time doing

00:26:23.390 --> 00:26:29.719
the same strategy but not get any hairs
and then lose some calories to the snow.

00:26:29.720 --> 00:26:32.130
If it stays there too long

00:26:50.950 --> 00:26:58.140
Walking so long in the footsteps of the
links has been a strange journey for lives.

00:27:04.900 --> 00:27:09.559
It strengthened her feeling
of belonging in two worlds.

00:27:09.560 --> 00:27:12.844
The elemental instinctive
world of the animal

00:27:12.845 --> 00:27:16.969
and the world of reason and
data which is science.

00:27:16.970 --> 00:27:21.199
The barrier between both
seems to have faded helping

00:27:21.200 --> 00:27:26.220
her feel intuitively what the
lynxes next move might be

00:27:34.750 --> 00:27:38.839
One of the good things that
we found out about working

00:27:38.840 --> 00:27:42.559
with links in the way that we
chose to is that you can find

00:27:42.560 --> 00:27:45.829
out a lot more about them
about what they do all day

00:27:45.830 --> 00:27:49.849
by following them through
the bush at just as if we

00:27:49.850 --> 00:27:55.009
were walking beside them as you can
by using radio collars and doing

00:27:55.010 --> 00:27:56.929
a lot of locations from

00:27:56.930 --> 00:28:00.634
telemetry so you\'d get the intimate
details of life of the lengths.

00:28:00.635 --> 00:28:04.339
And it\'s also very satisfying
personally as well

00:28:04.340 --> 00:28:08.749
as work wise to produce this kind of result

00:28:08.750 --> 00:28:13.909
and some days besides the personal
satisfaction of walking around you get

00:28:13.910 --> 00:28:16.069
a little bit of evidence
that helps to build

00:28:16.070 --> 00:28:19.189
the story of what that links does
over the course of the cycle.

00:28:19.190 --> 00:28:24.214
Sometimes at the end of the day of
blocking you might come across a scat and

00:28:24.215 --> 00:28:26.779
that bit of evidence although
it\'s not very exciting to

00:28:26.780 --> 00:28:29.839
some people it provides
for us a real treasure.

00:28:29.840 --> 00:28:35.989
You finally found something that\'s going
to provide a clue in your story of

00:28:35.990 --> 00:28:39.289
building the image of
how a links is hunting

00:28:39.290 --> 00:28:43.369
and eating over the course of
the change of the hair cycle.

00:28:43.370 --> 00:28:50.040
Step 3042 we have a cache.

00:28:50.640 --> 00:28:54.309
It\'s I don\'t know what\'s in the
cache on time going backwards.

00:28:54.310 --> 00:28:56.679
I will check it out now.

00:28:56.680 --> 00:29:01.839
It confirms what we found
out by observing as we

00:29:01.840 --> 00:29:07.029
walk both the hunting and the kill
sites that the links did over

00:29:07.030 --> 00:29:10.029
the course of the day before
when we were following it or

00:29:10.030 --> 00:29:13.299
perhaps the day after we put
all of those bits and pieces

00:29:13.300 --> 00:29:17.679
together both our observations and
the direct results of what we

00:29:17.680 --> 00:29:22.359
find in that scat namely the remains
of the animals that it consumed.

00:29:22.360 --> 00:29:25.059
We put that together to
form our story of the links

00:29:25.060 --> 00:29:28.880
and its relationship to the
hair in the boreal forest.

00:29:36.040 --> 00:29:41.764
Meanwhile the story of the relationship
between the trackers and the tract

00:29:41.765 --> 00:29:46.789
develops to a result of being so

00:29:46.790 --> 00:29:50.299
closely tied to that animal
that we maybe never saw

00:29:50.300 --> 00:29:53.839
but certainly came to know was
perhaps best summed up by

00:29:53.840 --> 00:29:57.364
one of the trackers who
said that many times

00:29:57.365 --> 00:30:01.114
it was like following a ghost
the links had been there.

00:30:01.115 --> 00:30:02.734
We knew something about it.

00:30:02.735 --> 00:30:05.989
We could feel something we
could record something.

00:30:05.990 --> 00:30:11.464
We certainly got something implanted
in our own sensibilities about it.

00:30:11.465 --> 00:30:16.110
And it was like walking
with ghosts as it were

00:30:22.390 --> 00:30:25.549
At home in the remote majesty of

00:30:25.550 --> 00:30:32.040
the northern forest Liz is often as
solitary as the animal she studies.

00:30:32.440 --> 00:30:35.959
Working alone means you can\'t daydream.

00:30:35.960 --> 00:30:38.689
You can\'t forget where you are at

00:30:38.690 --> 00:30:44.314
any given moment or how you\'re going to
get back or covering all the what-ifs.

00:30:44.315 --> 00:30:49.369
Part of the relationship you
have with being out there in

00:30:49.370 --> 00:30:54.724
the first place is the necessity
of being always aware.

00:30:54.725 --> 00:30:57.619
Always aware of what\'s around
you where you are and how

00:30:57.620 --> 00:31:00.379
it\'s changing and how
you are going to figure

00:31:00.380 --> 00:31:04.339
out where you are if it gets
so cloudy that you can\'t see

00:31:04.340 --> 00:31:08.404
and that you know the distance
and have a feeling for

00:31:08.405 --> 00:31:10.729
what the train\'s gonna
throw at you how you can

00:31:10.730 --> 00:31:15.109
negotiate stream when it\'s
frozen looks frozen but isn\'t

00:31:15.110 --> 00:31:18.799
underneath that layer of
overflow or being able to

00:31:18.800 --> 00:31:22.819
see and learn from all of
those things how to be able

00:31:22.820 --> 00:31:26.599
to keep on going comfortably and safely

00:31:26.600 --> 00:31:32.779
is a big part of why I like
doing that kind of thing.

00:31:32.780 --> 00:31:37.039
Snow-capped mountains neighborly finches

00:31:37.040 --> 00:31:40.789
And the storybook house in the
forest shared with her partner

00:31:40.790 --> 00:31:45.630
Peter make lives his life
seem like a fairy tale.

00:32:02.320 --> 00:32:07.519
No need for traffic reports
or smog advisories here as

00:32:07.520 --> 00:32:12.929
she commutes to her office on her
kick a Scandinavian invention

00:32:20.880 --> 00:32:24.009
The clue ONE project produced

00:32:24.010 --> 00:32:28.944
fascinating data on everything
from plants to large mammals.

00:32:28.945 --> 00:32:33.429
Although it\'s no over
monitoring still continues.

00:32:33.430 --> 00:32:41.430
Here Liz examines the lynxes Scat to
identify for bone fragments claws and teeth.

00:32:42.630 --> 00:32:46.959
For former job is predator
technician has now

00:32:46.960 --> 00:32:52.250
expanded to include small mammals
often thought of as prey.

00:32:54.420 --> 00:32:58.479
It was a revelation from one season to

00:32:58.480 --> 00:33:01.739
the next because I\'ve always
viewed the entire study area

00:33:01.740 --> 00:33:08.419
From the eyes of the species that I follow
around and feel the most in touch with and of

00:33:08.420 --> 00:33:11.419
course the technique we use made that

00:33:11.420 --> 00:33:15.559
possible you are actually following in
the tracks every day of this animal.

00:33:15.560 --> 00:33:18.439
You do develop a very close
and intimate feel for

00:33:18.440 --> 00:33:23.299
what that animal experiences
in its day-to-day life.

00:33:23.300 --> 00:33:27.529
So my view of the world has
been pretty much through

00:33:27.530 --> 00:33:32.940
the eyes of the predator and mostly
through the eyes of the links.

00:33:33.820 --> 00:33:41.314
Now all of a sudden dealing every day with
these hairs and small mammals and Squirrels.

00:33:41.315 --> 00:33:44.074
I start to see things quite differently

00:33:44.075 --> 00:33:47.359
And for me as an ecologist
that was a big step because it

00:33:47.360 --> 00:33:50.779
wasn\'t just in my own eyes that there

00:33:50.780 --> 00:33:54.829
was an evolution of thought
it was also in how I

00:33:54.830 --> 00:34:00.240
viewed my work does the science and the
ecology of things simply fit together better.

00:34:10.690 --> 00:34:14.209
While relaxing Liz can observe

00:34:14.210 --> 00:34:19.770
the furtive moves of a small mammal
reluctant to end up as dinner

00:34:25.420 --> 00:34:28.759
Life is pretty tough if you\'re
snowshoe hare if you make

00:34:28.760 --> 00:34:31.744
it through for years your ancient.

00:34:31.745 --> 00:34:36.199
So your chances of living very long are

00:34:36.200 --> 00:34:40.849
limited no matter which point
your your borne out in

00:34:40.850 --> 00:34:44.044
the cycle at its lowest

00:34:44.045 --> 00:34:51.469
fewer than 1% survived you at least partly
to changing birth rates and predation.

00:34:51.470 --> 00:34:57.274
At dawn Liz sets out to check traps
set overnight in the forest.

00:34:57.275 --> 00:34:58.849
It\'s hard to believe

00:34:58.850 --> 00:35:04.429
this tiny creature exerts such a huge
influence on the boreal ecosystem.

00:35:04.430 --> 00:35:09.510
Liz and her colleagues are
often hard-pressed to explain

00:35:11.310 --> 00:35:18.069
We came up with one analogy think of all the
animals that use the boreal forest that live

00:35:18.070 --> 00:35:20.724
there at some point in their life

00:35:20.725 --> 00:35:24.114
or that are there all the time
in large numbers are small.

00:35:24.115 --> 00:35:29.379
If you put all the moose in one pile you put
all the caribou in another pile and you put

00:35:29.380 --> 00:35:36.200
all the snowshoe hares in one big
pile which pile is the biggest.

00:35:36.270 --> 00:35:44.270
And almost always people say moose caribou
depending on which animal is the biggest.

00:35:45.175 --> 00:35:47.709
When in fact it\'s the peak of

00:35:47.710 --> 00:35:53.594
the snowshoe hare segfault snowshoe hares
are the biggest amount of biomass in

00:35:53.595 --> 00:35:57.769
The boreal forest so they must
when there are that many of them

00:35:57.770 --> 00:36:02.089
around have some kind of
effect on the vegetation.

00:36:02.090 --> 00:36:10.090
And it\'s equally easy to understand how
important they are for the predators that eat

00:36:10.940 --> 00:36:17.329
them data from the
colonial project show that

00:36:17.330 --> 00:36:20.959
predators drive the cycle both by killing

00:36:20.960 --> 00:36:25.519
hairs and by the stress they
cause inheres who survive.

00:36:25.520 --> 00:36:29.719
Stress levels measured by
blood tests affective female

00:36:29.720 --> 00:36:35.569
particularly lowering her fertility as
well as her ability to raise her young

00:36:35.570 --> 00:36:40.710
This pattern can carry over
into several generations.

00:36:46.270 --> 00:36:52.279
The keystone species of the
Boreal Forest snowshoe hares hold

00:36:52.280 --> 00:36:59.610
its complex infrastructure aloft take
them away and the system collapses

00:37:16.360 --> 00:37:24.360
Liz findings show that during this low only
one out of seven links remains in her area.

00:37:32.350 --> 00:37:40.350
When it comes to boom and bust cycles among
small mammals voles are not to be outdone.

00:37:40.385 --> 00:37:47.730
Two years after hair numbers peak volt
populations show a dramatic upturn.

00:37:55.390 --> 00:37:58.354
These blunt nosed creatures

00:37:58.355 --> 00:38:02.149
spend cold free winters under
an insulating do vey of

00:38:02.150 --> 00:38:07.110
snow where they breed and feed
to their heart\'s content.

00:38:24.700 --> 00:38:29.239
In the dark ages people
thought hairs suffered from

00:38:29.240 --> 00:38:33.679
melancholy and chewed wild
trickery to cure themselves.

00:38:33.680 --> 00:38:36.889
They hoped no hair ever cross their path.

00:38:36.890 --> 00:38:40.980
Believing hairs were witches in disguise.

00:38:41.050 --> 00:38:46.714
But their most interesting feature
to evolve is their droppings.

00:38:46.715 --> 00:38:50.344
The hair has already
eaten them once itself.

00:38:50.345 --> 00:38:55.009
Excreted again they provide
shrubs with rich fertilizer.

00:38:55.010 --> 00:39:00.379
Thus ensuring a bumper crop of
berries for bowls to harvest.

00:39:00.380 --> 00:39:05.478
Just as hare populations
fall voles increase

00:39:05.479 --> 00:39:11.040
providing a tiny though welcome
meal to a ravenous links

00:39:30.040 --> 00:39:36.709
Now all links in this part of the low will
still be largely making his living by

00:39:36.710 --> 00:39:39.349
killing hears but in between
those here kills it\'s gotta

00:39:39.350 --> 00:39:42.919
fill in somehow there just
simply aren\'t enough hairs.

00:39:42.920 --> 00:39:49.339
And in a year like this with low snow
depth and lots and lots of small mammals

00:39:49.340 --> 00:39:52.489
available it will probably make a switch to

00:39:52.490 --> 00:39:57.030
trying when it\'s easy to do so
getting some of those small mammals.

00:40:15.390 --> 00:40:19.119
We know they\'re there they\'re
eating small mammals we just

00:40:19.120 --> 00:40:22.464
don\'t know as cleanly
from the tracking data.

00:40:22.465 --> 00:40:28.029
How successful they are in the
attempts versus that kills.

00:40:28.030 --> 00:40:34.359
However one of the biologists watch DO links
over the course of an hour Mouseion in

00:40:34.360 --> 00:40:41.769
a field and out of 19 attempts
it got 13 small mammals.

00:40:41.770 --> 00:40:48.059
If that were anywhere near typical He would
have to get 50 of those to equal the weight

00:40:48.060 --> 00:40:51.199
Of a snowshoe hare for that
day which means that would

00:40:51.200 --> 00:40:54.304
be about four hours of constant mousing.

00:40:54.305 --> 00:40:57.619
That\'s a lot of activity for the links.

00:40:57.620 --> 00:41:00.600
That\'s a lot of effort to put out.

00:41:18.010 --> 00:41:24.649
They like to eat very carefully their prey.

00:41:24.650 --> 00:41:28.414
So often when they do get a mouse
or a wall or small lemming

00:41:28.415 --> 00:41:33.319
they\'ll step to the side and
take their time trying to

00:41:33.320 --> 00:41:36.019
separate the little bits
of intestines that they

00:41:36.020 --> 00:41:39.214
don\'t like but it doesn\'t
work as well with a mouse.

00:41:39.215 --> 00:41:41.449
This small thing that you can\'t hold with

00:41:41.450 --> 00:41:44.299
your claws and and carefully
separate things from.

00:41:44.300 --> 00:41:48.829
So in the end they will they usually
eat all of it but they just

00:41:48.830 --> 00:41:54.540
do it much more slowly than than a coyote
which takes it usually in one gulp.

00:41:56.800 --> 00:42:02.359
Soon the receptive snow that charts
the endless comings and goings of

00:42:02.360 --> 00:42:09.840
living creatures will have vanished making
tracking impossible for Liz until next fall

00:42:24.640 --> 00:42:32.640
Gradually winter loosens its grip giving
way to the heady excitement of spring.

00:42:36.670 --> 00:42:44.479
The snowshoe hare sheds its white coat
revealing a leaner less domestic personality.

00:42:44.480 --> 00:42:49.609
That gleam in its eye suggests
a survivor\'s giving this

00:42:49.610 --> 00:42:54.060
Evokes the old saying mad is a March Hare.

00:42:54.610 --> 00:42:58.069
But it hasn\'t lost all its senses.

00:42:58.070 --> 00:43:01.819
It\'s still alert to its
ever faithful shadow.

00:43:01.820 --> 00:43:08.250
The one who returns again and
again to its dream of dinner.

00:43:13.570 --> 00:43:17.239
Patients helps the links endure.

00:43:17.240 --> 00:43:20.704
The hair cycle may rise again this spring.

00:43:20.705 --> 00:43:25.024
And one day those who walk
with ghosts may reach

00:43:25.025 --> 00:43:30.449
even deeper insights into the
secrets of the boreal forest

00:43:36.840 --> 00:43:41.679
To purchase a transcript of tonight\'s
episode of the nature of things Email

00:43:41.680 --> 00:43:46.850
us at T NOT At Toronto. cbc dot ca