Original subtitles

Insects are disappearing

across the world.

If we lost our pollinators,

we would lose 80 to 90% of the plants on the planet.

That is not an option.

It's the ecosystems on this planet

that keep humans alive.

Scientists warn us

that the insect apocalypse

is entirely possible.

As we expand the human population,

we keep making these sterile landscapes,

and nature is pushed out.

Without the ecological services

that insects provide,

we are doomed.

(upbeat music)

Insects are the most abundant animals on earth.

It's estimated that the total weight

of our insect population

is at least 17 times greater than all of humanity.

They provide the essential services necessary

to support life.

They pollinate about 80% of all plants,

including about 75% of our food crops.

They decompose dead plants and animals

and thereby recycle nutrients back into the system.

They manage the soil,

and they are the essential food base

for other animals, especially birds and freshwater fish.

Annual ecosystem services provided

by wild insects in the U.S,

have been estimated at $57 billion.

Scientists have identified

and described about 66,000 animal and fish species.

In contrast, insect species add up to about a million,

and the number yet to be identified

could amount to another 20 million or more.

There are more than 160,000 kinds of moths in the world.

Butterflies add up to about 17,500 species.

There are nearly 20,000 types of bees

and more than 12,000 kinds of ants.

Beetle species total nearly 400,000.

In light of those huge numbers,

it's easy to believe that the insect abundance is endless,

but is it?

(upbeat music)

As these trillions upon trillions of insects remain busy

with the central ecological tasks,

entomologists and concerned citizen scientists

are noticing troubling trends

in the woods, fields and back yards.

Is it possible that the world's insect population

is beginning to crash?

Scientists knew there were serious ecological problems

stemming from habitat loss, climate change,

and the pervasive use of pesticides and herbicides.

But there was little data to quantify the extent

of the damage to insect populations

and nothing to support a global alarm,

until a long-term study

by a German entomological club came to light.

The Krefeld entomological society near Dusseldorf

has collected and curated insect specimen records

since 1864.

Over the years, these citizen scientists maintain

a rigidly consistent collection program,

and they preserved the insects they caught

using standardized nets

and meticulous identification and storage routines.

In later years, they were noticing fewer

and fewer insects filling their jars and boxes

from their seasonal trips

to 63 nature preserves representing virtually every type

of natural habitat in the region.

They employed a unique method of weighing their collection

and shared the results with university scientists

who confirmed a 76% seasonal decline

over the previous 27 years,

and the mid summer decline amounted to a shocking 82%.

It was time to sound the alarm.

Ecology professor and author, Dr. Dave Goulson

of the university of Sussex explains the situation.

There's one aspect of insect declines

that people have noticed,

particularly if they're of a certain age,

I guess maybe 50 or more years old.

I can remember when I was a kid,

that if we drove any distance in the summer,

we'd have to stop and clean the windscreen

of the car every hour or two,

because it would be literally impossible to see through

because it was covered in splattered insects,

today that just doesn't happen.

In 2014, a panel

of scientists synthesized current insect populations studies

and found that most of the monitored species

had declined on average by 45%.

This disappearance of insects

is something that people should take really seriously

because whatever you think about them,

insects are vitally important

to every single human on the planet.

They can be intimately involved

in more or less every ecological process

that you can think of: nutrient cycling,

keeping the soils healthy, breaking down dead bodies,

dead trees, leaves, bio control,

controlling pest numbers and so on and so on.

And most famously of course, they pollinate our crops.

75% of the crops we grow globally

require insect pollination.

So we wouldn't have a whole sway,

the fruits and vegetables that we require

to keep us healthy.

Everything from apples and cherries to blueberries,

raspberries, strawberries, tomatoes, squashes, pumpkin,

I could go on and on and on,

even includes coffee and chocolate

all require insect pollination.

So life would be pretty miserable without these things,

and the horrible truth is the millions of people

would starve to death if we didn't have insect pollinators.

So whatever you think about insects, we need them,

and we need to look after them.

So far as we know,

insect declines are being driven by a whole bunch

of different factors.

Probably the biggest globally is habitat loss

from the tropical forests

to the flower rich hay meadows of the UK.

In the UK we-

a hundred years ago,

we had about 7 million hectares

of flower rich grasslands, hay meadows, and Jordan.

They would have been teeming with butterflies

and bumblebees and all sorts of other insects.

And we destroyed 97% of it in the 20th century,

and so habitat loss is a big one,

but then on top of that,

and it's kind of associated with it,

a lot of that habitat loss is too intensive.

Farming, which involves

a lot of pesticide use,

a whole barrage of insecticides and fungicides

and herbicides going on to farmland all the time.

We shouldn't really be surprised if they disappear.

This issue seems to have come upon us quickly.

Large scale declines that have happened

within my lifetime,

and to think that, you know,

more than half the butterflies have gone

since I was a kid,

is really disturbing.

It's not just Europe,

it's certainly happening in North America,

there's good data on Monarch butterflies,

and how they've been fairing,

but they've all but disappeared.

Scientists estimate

that a complete insect population collapse

would mean the end of human life

within two months.

What then are our prospects for a positive outcome?

Good news,

insects can recover.

Rather few of them have gone extinct yet,

lots of them heading towards it

but if we take action now it's not too late.

And the nice thing about insects

is they actually breed very quickly

given the right conditions,

so they could recover in no time at all

if we gave them somewhere to live,

something to eat,

stop poisoning them and so on.

But insects need places to recover

and our scattered collection

of nature parks and forest won't be enough.

Right now,

at least 85% of the land East of the Mississippi

is privately owned,

and much of that property is a monoculture

of suburban and urban lawns,

or is being used for large scale food production.

Landscapes that for insect

and ecological purposes

might as well be parking lots.

In short we've drained, cut and paved nature,

and we've curved it into pieces too small

and isolated to sustain the native insects and animals

that make our ecosystems work.

Douglas Tallamy,

the chief entomology professor

at the university of Delaware,

has a New York times bestseller out,

"Nature's Best Hope".

And he has a plan.

(birds chirping)

If you look at the way we landscape,

humans are here and nature some place else,

and then there's no more someplace else's.

And as we expand the human population,

we keep making these sterile landscapes,

and nature is pushed out.

So that is why things are declining.

You might think

that with so many species of insects

in their abundance,

the system should be able to adjust

to human population expansion and lifestyles,

but that's not how it works,

in fact, 90% of the insects that eat plants,

develop and reproduce only on certain plants

with which they share an evolutionary history.

Specialization is really common

in the world of insects,

both with pollinators

and with the insects that eat plants.

We've got over 4,000 species of native bees,

and at least a third of them can only reproduce

in the pollen of particular plant genera.

And the reason all these insects are so specialized

is because plants don't want to be eaten,

they want to capture the energy

from the sun and use it

for their own growth and reproduction,

so they protect their tissues with nasty compounds,

and the insects have to adapt

to those phytochemicals in order

to be able to eat the plant.

So they develop specialized enzymes and behaviors

and life history adaptations

that minimize their exposure to these compounds.

The Monarch, for example, is good at milkweeds,

but it wouldn't be able to handle Oak trees,

and that's why if you want to have caterpillars

in your yard,

you need to have the plants that create those caterpillars.

They're not going to eat any other plants.

Why would you want caterpillars in your yard?

Well, if you want birds in your yard

you got to have these Caterpillar.

Chickadees, for example

take 6,000 to 9,000 caterpillars

to make one clutch of chickadees.

An insect apocalypse

would devastate the animals

that depend on them for food,

including humans.

We would lose at least a third of our crops,

and our food web would collapse.

If insects were to disappear,

particularly our pollinators,

it would hit certain aspects of our agriculture very hard.

The production of fruits and vegetables,

apples, for example, depend on bee pollination, tomatoes.

Most of the fruits are being pollinated.

So matter of fact, in China,

where they have lost a lot of their pollinators,

they've got guys up on ladders

with paintbrushes trying to pollinate peaches

and other crops that you know-

It's possible, but boy,

it is sure easier to keep the pollinators around.

The real reason we can't lose our pollinators

is because they're pollinating 80% of all plants,

and 90% of all flowering plants.

If we lost our pollinators,

we would lose 80 to 90% of the plants on the planet,

that is not an option.

So we need pollinators every place we need plants,

which is every place.

Anybody who's managing land anywhere,

in your yard, your corporate landscape,

your roadside,

they need to be making pollinators,

absolutely everywhere.

(suspenseful music)

So the familiar issues

of overdevelopment, pesticides

and our ever expanding population

are to blame for the insect population decline.

But what can we do about it?

Tallamy points out that the national parks and preserves,

while well-intentioned, only separate us from nature,

and cannot do enough

to foster the interconnectivity necessary

for biodiversity and recovery.

Meanwhile, across the United States and around the world,

millions upon millions of acres of land

are covered in lawn grass,

a symbol of prosperity and social order,

but otherwise an ecological wasteland.

More than 80% of the United States

is privately owned.

Tallamy sees that this is where we must join together

to create the solution.

We must practice conservation right where we live,

work and farm.

Dr. Tallamy notes,

that more than 40 million acres of land

East of the Mississippi,

an area, the size of new England

is dedicated to lawn space,

and turf grass does essentially nothing

to foster biodiversity.

He proposes the concept of a home grown national park.

Conservation has to happen everywhere,

which means we've got to learn

to share our human dominated spaces with nature.

The easiest thing for a typical homeowner to do

is think about reducing the lawn.

We have over 40 million acres of land in the U.S,

it's a dead space.

So I recommend cutting the lawn in half,

cut your area of lawn in half.

If everybody did that,

that would give us 20 million acres of land

we could use in conservation.

Replanting just half

of our lawn space with native plants,

especially flowering plants,

will support the insects

that support us and our food web.

We need the native plants to feed native bugs,

and even the odds for insect and human survival.

If we do this,

we will create ecological patches and corridors

that would equal an area

as large as all of our major national parks,

Yellowstone, Yosemite, the grand Tetons,

the grand Canyon, Denali, the great Smokies and so on.

We will be part of the solution

instead of part of the problem.

We've got to think about plants

as more than decoration,

they do important things,

and they've got to start performing

those ecological roles in our landscapes.

And if we choose the wrong plants,

the ones that don't perform those roles,

that creates local ecosystem collapse.

And if everybody does it,

then you get general ecosystem collapse,

and there are big ramifications to that.

It's the ecosystems on this planet

that keep humans alive.

They produce ecosystem services, you know,

oxygen, clean water, all that stuff.

That has to happen everywhere,

not just in little parks and preserves.

You can create a new national park,

call it Homegrown national park.

You know, 20 million acres

is bigger than all of our major national parks combined.

So you're going to choose those powerful plants,

I call them Keystone plants,

Oaks being the most important plant

you could put in your yard.

Another thing that any landowners should consider:

remove the invasive plants

that you have planted ornamentally

on your yard.

These things have run a muck in our natural areas,

and we end up with an understory

of invasive ornamentals from Asia

that aren't supporting our insects

because our insects have not been here long enough

to be able to come up

with the adaptations needed

to get around the chemical defenses

that are in those plants from Asia.

So it creates biological deserts,

and the most responsible thing we can do

is to make sure that our property

doesn't have any of those invasive plants on it.

Pollination is one

of the most critical functions

that insects perform,

and to accomplish that

they need to have good reasons to travel

from place to place,

and from yard to yard,

and across the country.

And they need to be on the job pretty much all year long.

Plant what we call pollinator gardens,

and it's simply a matter of adding flowering plants

to your landscape.

Pollinators need forage all season long.

There are native bees flying

from March to November in new England.

So in the rest of the country,

they're around nearly all the time,

which means we need blooming phases

as continuously as possible.

What more can we do?

Another very important thing we need to do though,

is think about light pollution at night.

We turn on our security lights,

we have our porch lights on,

everybody's got to have a light on.

Those lights are killing insects all the time,

and I understand people say,

"I gotta have my security light on

or the bad man will come."

If you put a motion sensor on your security light,

it only turns on when the bad man comes,

and the first thing you realize

is how often the bad man does not come.

If we create this homegrown national park,

we will bring nature essentially right to our living spaces.

Won't be like going to Yosemite,

it won't be like going to Yellowstone,

you won't have bison,

but you will have a lot of those specialized

natural interactions right in your yard,

and it'll give you the opportunity

to either create a personal relationship

with nature for the first time

or recreate one that you've lost

that you might've had as a child.

But particularly for our kids,

so many of our kids have never had a chance

to interact with nature at all.

(upbeat music)

If our kids can walk out their door

at their yard and get to establish

a relationship with some part of the natural world,

because it's right there in their yard.

Our kids are the future stewards of our planet,

and if they don't know what they're stewarding

or that they have to steward,

they're going to be lousy stewards.

So this is an investment in our future,

it's an investment in our current health,

there's all kinds of health benefits

to peaceful times in the natural world,

and it will save the biodiversity

that runs our ecosystems.

So, is this a big ask of a basic property owner?

And where's the proof

that this is worth the effort?

Tallemy's experience with his own 10 acre place,

just 15 miles from his office and university classrooms

has turned out

to be an ideal suburban ecological experiment.

He replaced the invasive plants with native species,

and so far he's counted and photographed

more than a thousand species of moths.

It's an indication of what a person

with minimal expense and experience can do

to be part of an ecological recovery.

My wife and I bought a farm

that had been broken up in Southeast Pennsylvania

with 10 acres,

but it had been mowed for hay.

I mean, there was not much there when we moved in,

and actually they had stopped mowing us for hay,

and what was there were all the invasive species

from Asia.

So our goal was to remove them

and put in native plants,

and in the meantime,

I started to realize how important all of this was.

About four years ago,

I had noticed so many moth species at our house

that I made it a goal to start photographing

as many as I could.

That would be my photographic record

of the number of species at our house.

I am up to 1,013 species of moths at our house.

The greatest benefit

of the homegrown national park concept

is that it will provide ecological corridors

for insects to use, to connect and thrive,

which will allow us to do the same.

Well, we've also recorded 59 species

of terrestrial birds that bred at our house.

That's 38% of all the terrestrial birds in Pennsylvania

on just 10 acres,

which simply says,

if you put the plants

that support our wildlife back into our spaces,

the wildlife will come.

It's not going to come after they're extinct,

so we we've got to do it soon.

World Wildlife Fund two weeks ago said,

well, we've lost two thirds

of the wildlife on planet earth since 1970,

and I'm thinking, "Not at my house."

We've gained at least two-thirds,

I'm sure we've increased biodiversity by more than that,

simply by putting the plants back.

So the message there is it's reversible.

This is not impossible,

it is a very gloomy statistic,

but if everybody made it a goal to recreate life

where they live,

85% of the U.S is privately owned,

or at least East of the Mississippi.

We'd be 85% done.

(upbeat music)