the west coast of the United States is
home to some of the Earth's greatest
natural wonders high in the California
mountains lives a pine tree over 5,000
years old farther to the north live the
Giant Sequoias towering at nearly 400
feet and just off the California coast
is another amazing life form an
underwater super algae that happens to
be one of the fastest growing organisms
in the world but the journey kelp forest
is notable for another reason the
astonishing number of species who live
there dr. Jenn Cassell and her team from
the marine science institute at the
university of california santa barbara
study the interplay between kelp and the
creatures who depend on it for survival
the kelp forest is completely
connectives connected to the deep-sea by
all these nutrients that drop down to
the deep part and provide carbon source
and it's connected to the land and
nutrients come from the land to feed it
if they get ripped out they are just
floating in the ocean can they ever drop
down and attach again they can't drop
down and attach again once they drift
but that drift algae is a really really
important thing because what they do is
they drop down and die and they provide
nutrients to other habitats so that
drift kelp is really important what
nutrients nutrients like nitrogen from
yeah so you see all this poop on the
cliff when it rains all that nitrogen
and other and phosphorus just comes
right down into the kelp forests and
feeds it like fertilizer I never thought
of that seriously ever I've never
thought to myself that bird poop up
there would help this entire ecosystem
that's so neat natural nutrients and
small amounts are good so now we're
gonna go down there and see how all of
this works together but I want to know
what's motivating you to get down there
to do these things why do you love kelp
I have so many motivations I do love
kelp but I admit I am a fish person I
love
fish weigh more than I love kelp okay
scientifically we're interested in how
the whole ecosystem functions together
and kelp to me
provides habitat for fish and food for
fish so I'm kind of a I'm a fish girl
all right let's go see it just like a
forest on land the kelp forest is home
to a wide variety of species and each
has an important role to play in the
overall health of the ecosystem as Jen
explains everything is dependent on the
kelp so what does a kelp forest do for
the other animals that live within that
area helps are really important for the
other animals because they provide the
habitat so like coral reef you picture
all this 3d structure helps provide even
more of that and in our kelp forests
there's definitely a number of keystone
species
remember the kelp itself is an algae and
it provides the home so to speak the
habitat and all of that but there are a
whole group of organisms called the
grazers and the main one and our kelp
forests or the urchins you know the
spiky guys they eat kelp and they can
mow down entire kelp forests if they get
too abundant but the good thing is as
you move up the food web there are
organisms that eat those grazers and in
our system in Southern California the
two main species are the California
spiny lobster which is an invertebrate
and a fish called the California
sheephead both of those including
actually a sea star called the sunflower
star all three of those species eat
urchins they kind of keep the system in
control and then above them really are
the human predators the California spiny
lobster it's a major fishery in
and people get the California sheephead
- so the humans are at the top along
with the marine mammals things like the
seals and the sea lions and the birds
it's a really interconnected web if one
of those levels gets out of whack either
goes away or becomes too abundant it
changes the whole forests healthy
ecosystems maintain a delicate balance
when that balance is upset it can be
devastating
just the kelp forest ecosystem have to
worry about invasive species
definitely yeah invasive species are
actually a huge problem in the marine
environment even though people don't
think of it as much as they do
terrestrial systems an algae from
Southeast Asia called Sargassum has come
into our system as proliferated hugely
is spread like wildfire and it's all
over our reefs now why is that bad
well it's changing the native ecosystem
and we're studying it but we're worried
that it's out competing the native kelps
it tends to blanket rocky reefs and in
areas where Sargassum has blanketed our
reefs we tend not to see the native
giant kelp there are very few success
stories of removals of large marine
invasions just fortunately a lot of time
and a lot of money a difficult
environment to work can you imagine are
you gonna put on your scuba tank and
remove acres and acres of an invasive
algae
Marine invasions in general especially
algae they're almost impossible to
reverse so we really need to put our
attention to preventing them not coming
in late and trying to clean them up a
lot of things are about prevention huh
the health of the health influences the
health of the ocean like the five
thousand-year-old Bristlecone pine and
the 400 foot Sequoia it's a priceless
treasure that must be protected
you