0:00:10.300,0:00:13.567
[TED intro plays]

0:00:21.030,0:00:25.529
Have you ever wondered what it's like[br]to be a tree?

0:00:25.530,0:00:27.598
Nobody.[br][audience laughs]

0:00:27.599,0:00:28.699
Ah, there's somebody.

0:00:28.700,0:00:31.589
See, I thought it was just me,

0:00:31.590,0:00:32.728
but for me, I think--

0:00:32.729,0:00:34.529
Oh, there's more of you out there.

0:00:34.530,0:00:38.159
But I think for me,[br]it's actually a side effect of my job.

0:00:38.160,0:00:40.739
I work on mountain pine beetle,

0:00:40.740,0:00:44.719
and this insect has the dubious honor[br]of having developed,

0:00:44.720,0:00:48.439
over just the last few years,[br]what is very likely

0:00:48.440,0:00:52.899
to be the largest insect outbreak[br]ever recorded by humans

0:00:52.900,0:00:54.679
on the planet.

0:00:54.680,0:00:56.959
And this tiny little insect,

0:00:56.960,0:01:00.109
the size and appearance[br]of a mouse turd,

0:01:00.110,0:01:04.759
has managed to kill millions[br]and, in fact, billions of trees

0:01:04.760,0:01:07.189
across vast landscapes.

0:01:07.190,0:01:09.079
Now, when I'm out working in the forest,

0:01:09.080,0:01:12.799
I actually do think about what it means[br]to be a tree.

0:01:12.800,0:01:15.589
Now, obviously,[br]they're quite different from us.

0:01:15.590,0:01:18.349
They're made of wood;[br]we're made of flesh and blood,

0:01:18.350,0:01:21.469
but I see another big difference.

0:01:21.470,0:01:23.141
Trees can't walk.

0:01:23.142,0:01:24.619
Trees can't run.

0:01:24.620,0:01:26.389
And trees can't hide.

0:01:26.390,0:01:27.767
And that means

0:01:27.768,0:01:31.639
that when a enemy[br]like mountain pine beetle shows up,

0:01:31.640,0:01:33.567
they have no choice

0:01:33.568,0:01:36.289
but to stand their ground.

0:01:36.290,0:01:40.969
Now, most of us,[br]when we think about trees,

0:01:40.970,0:01:44.209
we think about[br]these nice, gentle, passive,

0:01:44.210,0:01:46.319
benign organisms,

0:01:46.320,0:01:49.598
but nothing could be further[br]from the truth.

0:01:49.599,0:01:50.699
Trees

0:01:50.700,0:01:52.220
are dangerous.

0:01:52.221,0:01:53.969
[laughter]

0:01:53.970,0:01:57.029
I see some skeptics out there,

0:01:57.030,0:02:00.629
but really, put yourself[br]in the place of a tree.

0:02:00.630,0:02:02.009
What would you do?

0:02:02.010,0:02:03.606
Would you just stand there?

0:02:03.607,0:02:04.949
Would you fight back?

0:02:04.950,0:02:06.089
You'd fight back.

0:02:06.090,0:02:08.879
And that's exactly what trees do.

0:02:08.880,0:02:11.729
Trees are armed[br]with an amazing array

0:02:11.730,0:02:14.549
of physical and chemical weapons.

0:02:14.550,0:02:18.329
They fight back,[br]and they fight back really hard.

0:02:18.330,0:02:20.789
So if you're a mountain pine beetle,

0:02:20.790,0:02:23.759
trees pose a significant challenge.

0:02:23.760,0:02:25.229
In fact, it takes hundreds

0:02:25.230,0:02:27.509
and sometimes even thousands[br]of beetles

0:02:27.510,0:02:31.259
to kill a single tree.

0:02:31.260,0:02:33.329
Now,

0:02:33.330,0:02:36.179
if not enough beetles show up,

0:02:36.180,0:02:38.429
that's a dangerous situation,

0:02:38.430,0:02:42.001
because that means the tree wins[br]and the beetles die.

0:02:42.002,0:02:43.879
So it's actually very risky

0:02:43.880,0:02:47.299
to be a mountain pine beetle,

0:02:47.300,0:02:49.249
and even when they're successful,

0:02:49.250,0:02:51.619
it hardly seems worth the effort.

0:02:51.620,0:02:54.619
Trees[br]are the epitome of junk food.

0:02:54.620,0:02:57.349
Woody tissues have almost no nutrients,

0:02:57.350,0:03:00.469
and beetles can't live on wood[br]much easier than we can.

0:03:00.470,0:03:02.209
So how do they do it?

0:03:02.210,0:03:05.779
Well, guess what,[br]they do it the same way we do.

0:03:05.780,0:03:07.009
When they've been eating a lot--[br]well,

0:03:07.010,0:03:08.800
when we've been eating[br]a lot of junk food,

0:03:08.801,0:03:11.489
we pile on those nutritional supplements,

0:03:11.490,0:03:13.599
and that's exactly what they do,

0:03:13.600,0:03:16.935
only in a very different way[br]as you might suspect.

0:03:16.936,0:03:18.299
The beetles actually partner[br]with a couple of fungi

0:03:19.857,0:03:23.504
that provide to them[br]everything that wood cannot:

0:03:23.505,0:03:26.009
vitamins,[br]nitrogen to make proteins,

0:03:26.010,0:03:28.439
sterols to make hormones,[br]and so forth.

0:03:28.440,0:03:29.698
Pretty cool.

0:03:29.699,0:03:31.589
By partnering with fungi,

0:03:31.590,0:03:34.829
beetles can use trees[br]to raise their kids,

0:03:34.830,0:03:37.559
but being able to use a tree for food

0:03:37.560,0:03:42.059
is just the first step[br]in developing an outbreak.

0:03:42.060,0:03:45.119
What is it[br]that actually allows these beetles

0:03:45.120,0:03:48.299
to develop such huge numbers

0:03:48.300,0:03:51.479
that they can kill you,[br]if you're a tree,

0:03:51.480,0:03:53.669
and your family[br]and your friends

0:03:53.670,0:03:57.109
and, in fact, the entire forest?

0:03:57.110,0:03:58.745
Well, you'll hear from a lot of people

0:03:58.746,0:04:01.879
that the reason we have this big outbreak

0:04:01.880,0:04:04.969
is because we have unhealthy forests,

0:04:04.970,0:04:08.029
or because we have too many pines,

0:04:08.030,0:04:10.399
or because we have too many big pines,

0:04:10.400,0:04:13.309
or too many lodgepole pines,

0:04:13.310,0:04:15.559
that if we had only managed our forest,

0:04:15.560,0:04:17.929
none of this would have happened.

0:04:17.930,0:04:20.419
But that's not exactly true.

0:04:20.420,0:04:22.009
As you might suspect,

0:04:22.010,0:04:25.489
there's a little bit more[br]to that story.

0:04:25.490,0:04:29.509
So let me explain[br]how this big outbreak developed

0:04:29.510,0:04:32.719
and why this one[br]is so unusual

0:04:32.720,0:04:35.749
compared to those that we've seen[br]in the past.

0:04:35.750,0:04:40.129
First, you need to know a little bit[br]about the insect.

0:04:40.130,0:04:43.099
One thing,[br]outbreaks aren't new.

0:04:43.100,0:04:46.249
Mountain pine beetle is actually native[br]to western North America,

0:04:46.250,0:04:49.879
and it's been developing outbreaks there[br]for millennia,

0:04:49.880,0:04:53.239
and these outbreaks[br]are actually natural disturbances.

0:04:53.240,0:04:56.569
They help maintain and restore[br]the forest.

0:04:56.570,0:04:57.798
But, clearly,

0:04:57.799,0:05:01.019
beetles are not in outbreaks[br]all the time.

0:05:01.020,0:05:05.339
They only develop outbreaks[br]every few decades or centuries,

0:05:05.340,0:05:08.159
and only when you have two things:

0:05:08.160,0:05:11.579
you need to have lots of pines[br]on the landscape

0:05:11.580,0:05:14.069
that are big enough[br]for the beetles to use,

0:05:14.070,0:05:16.769
which is a condition we always have,

0:05:16.770,0:05:19.409
and a trigger.

0:05:19.410,0:05:22.139
So let me explain this trigger.

0:05:22.140,0:05:25.619
What you see here[br]is what a mountain pine beetle population

0:05:25.620,0:05:28.619
might look like[br]for a couple of hundred years,

0:05:28.620,0:05:30.749
and what you can see[br]is that the beetle

0:05:30.750,0:05:34.439
is present in very low numbers[br]most of the time.

0:05:34.440,0:05:36.509
And so at this point,[br]if you're a tree,

0:05:36.510,0:05:38.849
you should feel very safe,

0:05:38.850,0:05:40.499
because the beetles are actually

0:05:40.500,0:05:42.779
at the mercy[br]of their own low numbers.

0:05:42.780,0:05:44.399
There are so few of them out there,

0:05:44.400,0:05:47.219
they can hardly ever kill a tree,

0:05:47.220,0:05:50.857
and those few trees they actually kill[br]have disease or they're damaged

0:05:50.858,0:05:53.099
and can't fight back.

0:05:53.100,0:05:55.800
But of course,[br]somewhere along the way,

0:05:55.801,0:05:57.419
we get a trigger,

0:05:57.420,0:06:00.149
and for mountain pine beetle,[br]the trigger

0:06:00.150,0:06:01.813
is a change in climate

0:06:01.814,0:06:04.689
to warmer and drier conditions.

0:06:04.690,0:06:07.209
And at this point,[br]if you're a tree,

0:06:07.210,0:06:09.239
you should start to worry

0:06:09.240,0:06:11.219
because warmer temperatures

0:06:11.220,0:06:14.489
allow greater productivity[br]of beetle young

0:06:14.490,0:06:17.309
and greater survival[br]of their young over the winter,

0:06:17.310,0:06:20.039
and that means more beetles,

0:06:20.040,0:06:22.229
and drought stresses trees,

0:06:22.230,0:06:24.209
and that lowers their defenses,

0:06:24.210,0:06:27.749
and that lowers the numbers[br]of beetles it takes to kill them.

0:06:27.750,0:06:32.879
And very importantly,[br]drought stresses trees across regions,

0:06:32.880,0:06:35.069
so that's really big areas.

0:06:35.070,0:06:36.491
So if you're a tree,

0:06:36.492,0:06:39.359
this[br]is a really bad combo.

0:06:39.360,0:06:42.269
It means[br]you've got a lot of beetles out there,

0:06:42.270,0:06:44.999
but it doesn't take very many[br]to kill a tree,

0:06:45.000,0:06:48.059
and there's lots and lots and lots[br]of trees

0:06:48.060,0:06:50.169
that are easy to kill.

0:06:50.170,0:06:55.019
This situation allows the beetles[br]to rapidly build in population

0:06:55.020,0:06:56.988
until they reach a threshold

0:06:56.989,0:06:59.729
over which there are so many beetles

0:06:59.730,0:07:02.669
that they can even kill[br]healthy, defensive trees.

0:07:02.670,0:07:04.255
At this point,

0:07:04.256,0:07:07.349
tree defenses are inconsequential.

0:07:07.350,0:07:09.017
They no longer matter.

0:07:09.018,0:07:11.891
And, in fact, the beetles switch

0:07:11.892,0:07:13.199
to attacking healthy trees

0:07:13.200,0:07:16.529
because they're better food[br]for their young,

0:07:16.530,0:07:18.564
and better food for the young means...

0:07:18.565,0:07:20.309
more beetles.

0:07:20.310,0:07:23.429
At this point,[br]the outbreak is self-perpetuating,

0:07:23.430,0:07:26.909
and there's virtually nothing you can do[br]to stop it.

0:07:26.910,0:07:28.949
Now, once an outbreak initiates,

0:07:28.950,0:07:31.799
there's a couple[br]of potential end points.

0:07:31.800,0:07:34.379
One,[br]it can go to completion,

0:07:34.380,0:07:36.179
and that means that they--[br]the beetles,

0:07:36.180,0:07:38.819
kill most of the suitable trees[br]on the landscape,

0:07:38.820,0:07:40.829
and then their populations crash

0:07:40.830,0:07:43.079
because they're out of food.

0:07:43.080,0:07:47.309
But in the past,[br]this seldom ever happened.

0:07:47.310,0:07:49.589
You had the initiation of an outbreak

0:07:49.590,0:07:52.739
when you had[br]an abnormally warm, dry period,

0:07:52.740,0:07:54.856
but when things went back to normal,

0:07:54.857,0:07:56.669
got cooler and wetter,

0:07:56.670,0:07:58.229
then tree defenses came up;

0:07:58.230,0:08:00.689
beetle productivity went down,

0:08:00.690,0:08:03.209
and the beetles pooped out.

0:08:03.210,0:08:05.669
But the problem now is, of course,

0:08:05.670,0:08:07.529
that we're not expecting to go back

0:08:07.530,0:08:09.599
to cooler, wetter conditions.

0:08:09.600,0:08:12.149
The predictions[br]are we're going to get warmer

0:08:12.150,0:08:14.759
and in many places drier,

0:08:14.760,0:08:18.089
and that means[br]that going to completion

0:08:18.090,0:08:20.249
might be the new norm.

0:08:20.250,0:08:23.669
And if that's the case,[br]we need to be really concerned,

0:08:23.670,0:08:26.753
because that means really big changes

0:08:26.754,0:08:28.829
in our forest ecosystems,

0:08:28.830,0:08:32.038
and of course, then,[br]big changes in all those services

0:08:32.039,0:08:35.069
and functions that they provide.

0:08:35.070,0:08:37.319
Now, the current outbreak

0:08:37.320,0:08:41.369
is actually, or maybe,[br]a harbinger of things to come.

0:08:41.370,0:08:44.099
This outbreak is significantly different

0:08:44.100,0:08:46.719
than any we've seen in the past.

0:08:46.720,0:08:50.829
For one, it's <i>ten</i> times bigger,

0:08:50.830,0:08:52.079
ten times.

0:08:52.080,0:08:55.109
Now, that's pretty remarkable[br]in and of itself.

0:08:55.110,0:08:56.429
But there's more.

0:08:56.430,0:08:59.259
The beetle is actually on the move.

0:08:59.260,0:09:01.992
Because of warming,[br]the beetle has moved

0:09:01.993,0:09:05.207
several hundred kilometers[br]further north in Canada,

0:09:05.208,0:09:08.519
and it's now all the way to the Yukon.

0:09:08.520,0:09:11.309
It has jumped the Northern Rockies

0:09:11.310,0:09:13.979
and has spread across Alberta

0:09:13.980,0:09:17.189
and is now even invading Saskatchewan.

0:09:17.190,0:09:20.159
In this location in Canada,

0:09:20.160,0:09:22.799
the beetle[br]is in a new place;

0:09:22.800,0:09:25.319
it's in a new species of tree,

0:09:25.320,0:09:28.589
and that makes it an exotic.

0:09:28.590,0:09:30.359
And we know that exotics

0:09:30.360,0:09:32.159
are seldom very good

0:09:32.160,0:09:34.679
for our native ecosystems.

0:09:34.680,0:09:38.009
The beetle is expected to continue[br]to move across the continent,

0:09:38.010,0:09:39.722
through the boreal forest

0:09:39.723,0:09:42.989
and into our eastern pine forests.

0:09:42.990,0:09:46.439
Because of warming,[br]the beetle has also moved up in elevation

0:09:46.440,0:09:49.079
where it's wiping out white bark pine.

0:09:49.080,0:09:53.279
This is a tree that used to be protected[br]from the beetle by cold,

0:09:53.280,0:09:56.879
but now the devastation[br]is so extensive and severe,

0:09:56.880,0:09:59.039
this critically important tree

0:09:59.040,0:10:01.559
is now being recommended for listing

0:10:01.560,0:10:04.079
as an endangered species.

0:10:04.080,0:10:06.899
And all of this[br]has been due

0:10:06.900,0:10:10.409
to a warming climate.

0:10:10.410,0:10:13.139
Now, I mentioned[br]that this particular outbreak

0:10:13.140,0:10:15.929
is far outside the historic norm,

0:10:15.930,0:10:18.509
and as such, in many locations,

0:10:18.510,0:10:21.929
the beetle is no longer restorative[br]for the forest,

0:10:21.930,0:10:23.489
but damaging.

0:10:23.490,0:10:26.289
Effects on water,[br]vegetation,

0:10:26.290,0:10:28.379
wildlife,[br]local communities,

0:10:28.380,0:10:31.889
and economies[br]have been massive.

0:10:31.890,0:10:33.179
And human responses,

0:10:33.180,0:10:35.159
for better or for worse,[br]to the outbreak

0:10:35.160,0:10:39.029
have added an additional level[br]of impact.

0:10:39.030,0:10:40.290
At this point,

0:10:40.291,0:10:42.109
if you're a tree,

0:10:42.110,0:10:43.990
you should not only be worried;

0:10:43.991,0:10:47.299
you should be shaking[br]in your roots.

0:10:47.300,0:10:50.350
[person laughs][br]Sorry, bad one.

0:10:50.351,0:10:52.109
[laughter]

0:10:52.110,0:10:54.629
Couldn't help it.

0:10:54.630,0:10:58.439
But, also, if you think about this--[br]this outbreak,

0:10:58.440,0:11:02.399
it's really tempting to think of it[br]as a local issue:

0:11:02.400,0:11:05.279
It's just western North America,

0:11:05.280,0:11:08.339
but actually, the implications[br]are global.

0:11:08.340,0:11:12.149
Trees are incredibly important sinks[br]for carbon,

0:11:12.150,0:11:14.009
but when vast areas die,

0:11:14.010,0:11:16.019
they become sources.

0:11:16.020,0:11:18.149
In the worst year of the outbreak,

0:11:18.150,0:11:21.839
carbon emissions from beetle kill[br]in British Columbia alone

0:11:21.840,0:11:25.109
are predicted[br]to have equaled the carbon releases

0:11:25.110,0:11:27.809
from fires[br]across all of Canada

0:11:27.810,0:11:31.319
for the preceding forty years.

0:11:31.320,0:11:33.200
Those kinds of carbon releases

0:11:33.201,0:11:36.239
obviously can feed back[br]to affect humans

0:11:36.240,0:11:39.629
and ecosystems[br]all around the world.

0:11:39.630,0:11:42.329
Now something else[br]to actually think about as well

0:11:42.330,0:11:44.579
with mountain pine beetle[br]is to realize

0:11:44.580,0:11:47.279
that this situation is not unique.

0:11:47.280,0:11:50.489
Climate-driven tree die-offs[br]are happening right now

0:11:50.490,0:11:52.169
all over the world.

0:11:52.170,0:11:55.199
Take, for example,[br]the giant Euphorbia tree

0:11:55.200,0:11:56.969
that I work on in Africa.

0:11:56.970,0:11:59.639
It's being mass attacked[br]by ambrosia beetles.

0:11:59.640,0:12:02.429
These are tiny, little beetles

0:12:02.430,0:12:04.379
related to the mountain pine beetle,

0:12:04.380,0:12:06.989
but they're typically not a problem.

0:12:06.990,0:12:09.359
But because of increasing temperature,

0:12:09.360,0:12:11.549
decreasing precipitation,

0:12:11.550,0:12:13.349
these trees are stressed,

0:12:13.350,0:12:16.289
and the beetles are responding.

0:12:16.290,0:12:19.319
This iconic poison arrow tree[br]of Africa

0:12:19.320,0:12:21.539
is very likely to disappear

0:12:21.540,0:12:23.489
from many portions of its range

0:12:23.490,0:12:26.849
just over the next decade.

0:12:26.850,0:12:30.809
The massive piñon bark beetle ips[br]in the southwestern US

0:12:30.810,0:12:33.539
has been so severe and extensive

0:12:33.540,0:12:37.439
that many of these forests[br]are not expected to recover.

0:12:37.440,0:12:39.749
Over eighty tree species[br]around the world

0:12:39.750,0:12:43.019
are known to be in trouble[br]due to climate change,

0:12:43.020,0:12:45.209
and likely there's a whole lot more

0:12:45.210,0:12:48.509
that we haven't yet recognized.

0:12:48.510,0:12:50.639
So, what do we do?

0:12:50.640,0:12:51.962
What do you do?

0:12:51.963,0:12:53.399
What do I do?

0:12:53.400,0:12:55.709
What do the trees do?

0:12:55.710,0:12:58.349
Well, unfortunately,[br]we can't just go out there somewhere

0:12:58.350,0:13:00.989
and turn down a thermostat.

0:13:00.990,0:13:02.858
We can't lay out

0:13:02.859,0:13:06.209
thousands and thousands of miles[br]of irrigation,

0:13:06.210,0:13:08.669
even if we could come up[br]with the water.

0:13:08.670,0:13:12.239
And logging won't do much[br]if it's driven by climate.

0:13:12.240,0:13:15.329
So we need to finally go[br]to the root of the problem

0:13:15.330,0:13:18.449
and do something about our emissions[br]of greenhouse gasses,

0:13:18.450,0:13:20.489
and we need to do it soon.

0:13:20.490,0:13:24.599
We also need to develop[br]new tools and approaches to our forests.

0:13:24.600,0:13:26.009
We need to move away from thinking

0:13:26.010,0:13:28.169
that logging will fix everything,

0:13:28.170,0:13:30.059
and we need to start working[br]with our knowledge

0:13:30.060,0:13:33.119
of genetics and adaptation.

0:13:33.120,0:13:37.169
And very importantly,[br]we need to remember

0:13:37.170,0:13:39.109
that trees can't walk;

0:13:39.110,0:13:41.039
trees can't run,

0:13:41.040,0:13:43.209
and trees can't hide,

0:13:43.210,0:13:45.299
and with increasing stress,

0:13:45.300,0:13:49.855
trees are going to have fewer[br]and fewer defenses at their disposal,

0:13:49.856,0:13:53.009
and somehow it's going to be up to us[br]to get them through.

0:13:53.010,0:13:56.328
I hope I've opened some eyes[br]and minds tonight about the threat

0:13:56.329,0:13:59.399
that a warming climate poses[br]to our forests,

0:13:59.400,0:14:02.189
but I also hope[br]I've helped people recognize

0:14:02.190,0:14:05.684
that these threats are not just[br]through effects on the big things,

0:14:05.685,0:14:07.194
like ice shelves

0:14:07.195,0:14:08.509
and sea level rise

0:14:08.510,0:14:09.949
and extreme weather,

0:14:09.950,0:14:12.389
but through their effects[br]on the little things,

0:14:12.390,0:14:14.249
like a tiny little insect

0:14:14.250,0:14:15.808
the size and appearance

0:14:15.809,0:14:17.429
of a mouse turd.

0:14:17.430,0:14:19.851
Thank you.

0:14:19.852,0:14:22.525
[applause]