(board scratching) - They're cute, they're majestic, but why should you care about marine mammals?

Are they really that important?

Even if you live hundreds of miles inland, you are more connected to the ocean than you may think.

Every breath you take is connected back to the sea.

(bright music) And marine mammals are one of those puzzle pieces that keep our ocean's ecosystem in balance.

Without them, well, that's something we don't want to find out.

Marine mammals have all the typical characteristics of land-dwelling mammals.

They breathe air, give birth to live young, and nurse them with milk.

California's marine mammals include humpback whales, dolphins, seals and sea lions, and sea otters to name a few.

(pensive music) The biggest difference is they spend all or most of their time in the ocean, so they've had to adapt to the extremes of living in the sea.

These adaptations vary by species, ranging from dense fur and blubber, the use of echolocation, and modified appendages, to high levels of hemoglobin in their blood for storing extra oxygen while diving.

Such traits have allowed marine mammals to thrive in cold temperatures, low light, and extreme pressure, AKA places we humans can't go without thick wetsuits or extra dive gear.

(waves crashing) As some of the top predators in the sea, marine mammals play an important role in the food web and help ensure balance in the ocean's complex ecosystem.

(pensive music) Without them, overpopulation of prey species could quickly result in food shortages and overpredation of smaller species.

(pensive music) For instance, sea otters eat urchins, which reduces urchin predation on kelp.

This allows kelp forest habitats to thrive, preventing shoreline erosion and promoting biodiversity.

And sea otters aren't the only heroes of the sea.

Did you know that whales are also important for carbon sequestration?

When a whale dies, its carcass sinks in a process called whale fall, taking the stored carbon with it to the ocean floor.

And these are just a few examples.

Despite marine mammals being crucial to our oceans and our communities, they're facing an onslaught of challenges, particularly from us humans.

Marine mammals are particularly vulnerable to inadvertent human activities, such as certain fishing methods, shipping traffic, and increasing ocean noise and climate change.

Many marine mammals, including seals, porpoises, and dolphins, become victims of bycatch, meaning they are unintentionally caught in fishing and gear alongside target species of fish.

Discarded commercial fishing material also poses a huge problem for marine mammals, which can get tangled and stuck.

Plastic waste also threaten submarine mammals, as they can accidentally ingest or get tangled in it, causing injuries and infections that can be fatal.

We spoke with Dr. Cara Field at the Marine Mammal Center to hear a bit more about the challenges facing marine mammals today.

- You see a lot of hard cases, and I think things like entanglements, things that are animals that have been impacted by like ocean trash, or debris, or something like that.

And those are the ones that I want to like scream about 'cause they're so obviously human induced.

And those are the ones that I'd lecture my friends about, like, are you cutting the loops on your stuff?

Like, are you using reusable shopping bags?

Because I see the effects of when we don't do that every day.

You realize just how strong humans' presence are on this planet and how unbelievably much we have changed things just in the short time that we've been here.

- [Meg] Cara oversees the health and care of the center's marine mammal patients, and has helped all sorts of marine mammals throughout her long career.

And things are definitely changing, whether you can see them or not.

(mellow music) - We see things like extreme weather changes.

We can see decreases in populations of animals or changes in where they go.

Like, for wildlife, for these animals that we see, we can see huge impacts when their prey moves offshore and young animals can't find enough food, and they wash up in hundreds and thousands, and starving, and that is really highly visible.

But that's not always the case, there's always fluxes in there.

And so I think it's really incumbent on us to understand what those changes are.

What is the impact that we are having in causing those changes?

And I think climate change may be very real to people that live very close to where you can see things like loss of lots of... Loss of beaches, for example, or erosion on people's homes.

But not everybody sees that.

So, for those people that it's not so visible for, it may be a little bit of an out of sight, out of mind, as we humans tend to do.

So I think all of us need to realize how important, how big the impact is on all of us, and that it is something that we can combat.

(waves crashing) - It doesn't matter whether you call the desert, the city, or the coast home.

Our actions impact marine mammals.

These creatures are critical for healthy fisheries and a stable climate.

And good news, your everyday choices matter.

Simple acts like bringing reusable bags, organizing beach cleanups, and supporting your local wildlife organizations truly add up to make a really big difference.

- We've had such a massive impact on this planet, and the animals have no say in this, they have no role.

They can't fight back, they can't tell us like why it's so important that they're here, that, you know, we're all so interconnected.

But what humans are very, very focused on our lives and our situation without realizing just how important we are linked to everything on this planet.

We can solve it if we work together.

(mellow music) (waves crashing) - California's coastline is a dynamic environment, but marine mammals show us that even in the face of change, hope and progress can happen.

Their story is a powerful reminder of the impact collaborative efforts can have, inspiring us to be better stewards the ocean.

(waves crashing) Until next time, happy exploring.

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