[Narrator] Around 90 species of whale call our oceans home,
with many of them regularly making vast migrations across our planet,
some the equivalent of halfway around the world.
As they move through the depths,
they play key roles in the health of the ecosystems that they visit.
[Joe Roman] Whales dive deep to feed, picking up those nutrients.
They’re coming to the surface,
where they breathe, they rest, they digest and they poop.
Nutrients that have been locked away for tens of years come to the surface,
so whales are creating this pump.
Whales are basically fertilising their own gardens.
There can be more fish, more seabirds.
[Narrator] This movement of nutrients up from the depths
has been termed the “whale pump”.
It provides a fertiliser for one of the most important
and almost invisible links in marine food chains – phytoplankton.
These microscopic algae collectively generate
around half of the oxygen in the air we breathe,
and lock up carbon dioxide from the atmosphere in the process.
[Joe] We’ve long thought about animals,
that their role in the carbon cycle is basically like humans.
Sure, they breathe carbon dioxide.
But this whale pump increases the amount of phytoplankton in a particular area,
and when that dies, some carbon sinks down to the bottom of the ocean.
So, by increasing productivity in the oceans,
whales can help draw down carbon.
[Narrator] Whales also accumulate carbon in their bodies throughout their lives
and when they die, they sink to the deep sea,
sequestering that carbon for decades.
Restoring whales to pre-whaling numbers
could lock up tens of thousands of tonnes of carbon each year.
But the ways we are impacting our oceans,
from increased shipping to the effects of climate change,
are putting many species of whale at risk of extinction.
[Joe] If we were to lose whales –
think of the awful situation where they disappeared from ocean ecosystems –
what we would lose is not only these animals,
but also the ecological functions that they play,
one of the essential ones being the whale pump.
[Narrator] We have come close to losing our planet’s whale species before,
until most commercial whaling was banned in 1986.
While species like the blue whale are making a steady recovery,
others are still at real risk of extinction,
such as the North Atlantic right whale.
The latest estimate for the North Atlantic right whale population is about 336
individuals total, and only 70 of those are reproductive females.
If the population continues on this downward trend,
where we’ve lost about 30% since 2010,
this population will become functionally extinct
in probably about 20 to 30 years, possibly sooner.
Nearly all North Atlantic right whale deaths over the past two decades
have been due either to entanglement or to vessel strikes.
Most frequently it’s in the vertical line that goes
from something on the bottom of the ocean
up to a buoy where, you know, fishermen retrieve their gear.
For the right whales that are able to break free of the gear,
I mean those wraps of line actually cut into them.
And so what we end up seeing is that these whales take, on average,
about six months to die,
and they’ll die these slow, painful deaths.
[Narrator] It’s thought that over 85% of right whales
have been entangled in fishing gear at least once.
In the Gulf of Maine, work is under way to reduce these odds.
[Rob Martin] I became a lobsterman.
That’s all I ever wanted to do since I was a little kid.
It’s been in my family for seven generations.
But in 2014, we were faced with a closure for North Atlantic right whales.
It was over 3,000 square nautical miles.
To me, it affected probably a third of my earning income potential.
We were not able to get into parts of a closed area,
so that led us to on-demand gear.
[Narrator] This game-changing technique uses remotely triggered lifting devices,
which keep potentially lethal vertical lines out of the water.
This evolving technology could eventually allow those who use it
to fish through ongoing seasonal closures.
[Rob] The technology is moving really quick.
A lot of the NGO community are purchasing the gear,
the federal government is purchasing the gear.
A lot of people feel negatively,
but I always tell guys, if you’re affected by a closure,
this is an opportunity to get back fishing.
It helps protect the whale and also the fishermen.
It’s a win-win situation for both.
[Narrator] Not only do whales remove carbon from the atmosphere,
but if we can find a way to protect them using innovative techniques like this,
they could help to make our oceans more productive places.
Across our planet, around 3 billion people rely on fish
and other seafood as a primary source of protein.
Many through small-scale local fisheries
rather than large-scale commercial fishing.
More productive oceans are better able to support these communities,
directly benefitting both their livelihoods and their health.
Finding solutions that work for people and wildlife
are key to building a sustainable future for all life on our planet.
[Rob] Most fishermen, we’re very conservation-minded.
If we weren’t, we wouldn’t have a fishery.
I don’t want to see anything go extinct.
[Dr Sharp] We know that people don’t want these whales to die.
I really do see this species as the canary in the coal mine,
where they’re telling us that there’s a big problem out there
and it’s our job to fix it.
[Joe] It’s that whole-systems approach that’s going to be
the only way we’re going to save whales,
the only way we’re going to save oceans,
and really the only way we’re going to save ourselves.
