What happens when you remove two to three  million whales…in a very short period of time?

If you lived in New England in the mid-to-late  19th century, chances are the flames lighting   your home, just like the ones guiding ships  back to shore, were powered by whale oil.

And our mass consumption of  these gigantic mammals didn’t   just change our lives - it altered  the makeup of the entire oceans.

How could just a few decades of human  exploitation have such a global impact?

That’s what I wanted to know, and how I ended up  in one of the strangest places I’ve ever visited.

I’m Shane Campbell-Staton,  and this is Human Footprint.

Welcome to the Land of Giants here.

Wow.

Aw, see hell to the yeah, this is crazy.

How many whales do you have here?

We have every species that's on the  planet represented in our collection.

Nick Pyenson is a biologist who studies ancient  whales, so he spends a lot of time with fossils   that are tens of millions of years old.

But  he’s no stranger to living whales, either.

If there's a question about whale diversity  and evolution, you can probably find an answer   with one of these specimens.

This is Nick’s happy place:   a Smithsonian storage facility in  Maryland he calls “The Whale Warehouse.”   I know every collection has its unique smell.

But   what the hell is it that I'm smelling right now?

So you're smelling whale oil just everywhere and   it's whale oil that's hundreds of years old that  still hasn't really leached out of the bones.

Seeping out of the bones now.

Yeah.

Let me have you take a deep  whiff of this one over here.

Oh man, you just get way up in there.

Well, it's biology.

You got to get…   All up in the business.

Alright  let’s… yeah, oh God yeah.

So I have my own way of describing  that.

… It feels like knowledge to me,   but maybe to you it’s just death warmed over.

There's basically, there's knowledge in   the stank is what you're saying?

I might borrow that in the future.

So why is it like that?

Well, these animals  have blubber in life.

Fat is really important   for sustaining themselves.

These animals live  in very large environments where their food is   patchy.

You need to have a lot of fat reserves to  make it so that, you don't eat every day.

But when   you do eat, you just feast, store it and then  end up migrating sometimes really, really far.

So fat is a really important part of their life   history and it ends up in their  bones all around their bodies.

Okay.

So they're not just big  boned is what you're saying?

That's a really good way of putting it.

Now I’ve seen a lot of biological specimens in a  lot of museum collections, but nothing like this.

So here are the jaw bones - What the hell?

These are the jaw bones of a blue whale.

Bruh.

This is ridiculous.

Inside are the jaw bones of a   bull sperm whale that was 60 feet long.

The owner  of the blue whale jaw bones was 92 feet long.

Whoa.

And here's the crazy thing.

You are   looking at the largest single bone in the history  of life.

There is no dinosaur bone, mammoth tusk,   nothing is as big as this bone.

Wow.

So this is it.

And we'll never   collect something like this again.

These are blue whales from the southern   ocean.

And this was collected at a time when there  was still a lot of whaling going on, especially in   that part of the world where some two to 3 million  whales were killed.

… This was one of them.

Even the biggest animals that ever  lived aren’t off limits for the   planet’s Top Predator.

But why?

I mean,  there’s got to be an easier way to eat.

So, here we have a gray whale skeleton  that's at least 1000 years old   and it's from the coast of North  Carolina.

And I can show you right here,   you have these nice butchery marks right there.

Our ancestors in the human lineage were   using stranded whales as a resource  either for meat, maybe for the bones.

But at some point, stranded  whales weren’t enough any more.

So at some point there's like two dudes sitting on  the beach and one turns to the other.

It's like,   oh man, you see that gargantuan thing out there?

Let's go get it.

Bet money I can kill it.

I think that bet probably   ended badly most of the time.

The technology to  actually have a successful hunt really didn't   come together until about 1000 years ago.

And the purpose of that hunting, was it   for food or other purposes?

For mostly not for food,   but for oil.

Whale oil was really, really  good.

Great lubricant, burned really cleanly…   Whale oil lit New England in the middle to  late 19th century.

And it was only with the   discovery of actual petroleum, oil from the  ground where it no longer made economic sense.

The efficiency of 20th-century  whaling had a devastating impact.

We didn’t actually know how many whales there  were in the world’s oceans, so why did it matter?

There was just no limits.

There were so  many whales in the Southern Ocean, why not?

So, by the U.S. Marine Mammal  Protection Act in 1972,   99% of the blue whales that  were alive in 1900 were gone.

How do we know that number specifically?

Whaling is an industry that kept logs and   data.

There are 37 volumes like this and they  all have page after page after page of individual   whale.

And when it was killed, the whale number,  male, female and measurements of its carcass… Flipping through these pages is almost like  watching whales disappear all over again.

People guess that it's in maybe the few 100s.

600,   800 blue whales globally made  it through the 20th century.

It turns out that these ocean giants have a  massive role to play in ocean ecosystems.

You could add up the biomass of all the wild  mammals on the planet today.

… Just think   about tigers, lions, elephants, all the wild  mammals on the planet.

The level of biomass of   whales before industrial whaling was some  two, maybe three times as large as that.

So, the number of whales that were removed... Just in a few decades, not even in 100 years.

Was two to three times the total biomass of all  wild mammals that exist on this planet today?

And it’s not just the whales themselves that the  ocean lost, but all the things they did… Like eat.

So, here's a jar of krill.

Okay.

And this is the stuff  that giants are made of.

Exactly.

Yeah.

It's a really good way of putting  it.

And in the southern ocean there's more krill   than basically anything else.

So in a geological sense,   the age of ocean giants is still young…  but we already came close to ending it.

So if the giants are gone, are our  oceans just stocked full of krill now?

Yeah, so, that's the krill paradox,  right?

Removal of whales... Is that what it's actually called?

That’s what it's actually called in literature.

That's what people have been calling  that for decades.

The krill paradox.

Wow.

That'd be a great band name.

Yeah.

So, the krill paradox is that with the  removal of whales, you expect … there'd be   so much more krill, turns out that's not the  case.

Krill have actually dropped in numbers.

How does that work?

Well, so there's a   feedback loop here, and it goes back  to whales feeding and then pooping   in the upper layers of the water  column right in the photic zone.

The “photic zone” is the layer of water near   the ocean’s surface where light can  penetrate and plant life can grow.

Whales spend a lot of time deep underwater, but  they have to surface to breathe… and it turns out,   that’s where they do most of their pooping, too.

So, when whales aren't there, they are not   fertilizing the oceans as much  as they otherwise would be.

They're mobilizing nutrients.

So, that includes  phosphorus or nitrogen… And phytoplankton,   zooplankton, like krill – they're going  to need these nutrients to build these   incredibly productive, healthy, food webs.

So whales are dependent on the krill,  but the krill are also dependent on the   whales.

Whales are essentially, kind of  in a way, farming krill with their poop.

And that's why we call them ecosystem engineers.

The chemistry of the oceans, too, changed with the   removal of all those whales.

Wow.

I think it's a source of wonder to live  alongside some of the largest species,   not just on the planet right now, but  to have ever evolved in the history of   life on this planet.

How lucky are  we?

And we nearly snuffed them out.

Now the fortunate thing is  they didn't go extinct.

… So,   I kind of think we have a second chance in  the 21st century to make a greater impact.

Thanks for watching!

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