Sea Stars | JONATHAN BIRD’S BLUE WORLD


You might not think of sea
stars as being very
intelligent, and you’d be
right, but you might be impressed by some
of the amazing things they can
do, especially considering they don’t have a brain! Hi, I’m Jonathan Bird and
welcome to my world! ( ♪ music ) Starfish, more correctly called
sea stars, live just about
everywhere in the ocean, from the tropics, to Antarctica and
everywhere in between. They
come in all shapes and sizes from fat and stubby… to long
and skinny. This brittle star walks with a
coordinated effort using its
rays like legs. But most sea stars get around
using hundreds or thousands of
tiny tube feet on their
underside. This is a Northern Sea star,
living in the coastal waters of
New England, and it’s a predator. It’s hunting a scallop. It’s a
drama played out in slow motion
as the sea star moves in for a grip on the scallop’s
shell. But the scallop is not
defenseless. With a mighty
blast of water, the scallop
jets away to safety. So the sea star wraps itself
around a mussel. Mussels are
attached to the bottom and can’t get away. The sea star uses it’s strong
tube feet with suction cups to
pull the mussel open a tiny bit, and digests its
victim by injecting its stomach
inside the mussel. Picking up the sea star, I can
see that it has the mussel
firmly in its grip. But not all sea stars feed on
mussels and scallops. A Basket
star feeds on plankton in the water. It has finely
branched arms that act like a
net, to catch the tiny bits of food floating by. It
positions itself to be able to
grab as much plankton as
possible in the current. Some sea stars eat something
even more surprising. Come take
a look! Exploring a reef in the
tropical Pacific, I find a
Crown-of-thorns sea star dining
on the coral. This thorny, armored sea star
is one of only a few animals
that can digest living coral. It wraps itself around a coral
colony and eats the polyps,
leaving a dead, bleached coral skeleton behind. Here’s a healthy colony of
plate coral. And here’s one
that has been eaten by a crown-of-thorns. Outbreaks of
these sea stars have been known
to kill entire reefs. Carefully picking one up to
avoid the sharp and venomous
spines, I can see the stomach, which the sea star inverts out
of its mouth to digest the
coral outside of its body. These sea stars are the second
largest in the world, growing
bigger than a dinner plate. But if you think these are big,
wait until you see the largest
sea star in the world! To find it, I’ve come all the
way to British Columbia. I’m
looking for the Giant Pacific Sun Star, and you won’t believe
the size of this thing!
In the cold, murky waters of
the Canadian north Pacific, I
swim through beautiful gardens of sponges, anemones and soft
coral, searching for a Giant
Sun star. And then, down on the bottom, I
find what I’m looking for. It
has up to twenty-four arms, more properly called rays
and reaches three feet across.
WOW! This is the world’s largest sea star! Compared to most sea stars, the
Giant Sun Star is a speed
demon, cruising along the bottom in search of its
favorite food—other sea stars
and the occasional sea cucumber! Here, a sea cucumber makes an
emergency retreat to escape
this hungry Sun Star on the
move! A thousand miles south on a
reef in the tropics, I find a
blue Linckia sea star on the
bottom. Like the vast majority of sea
stars, this one has only five
rays. With tiny tube feet on its
underside, this sea star barely
seems to move, but when I speed things up with time lapse
photography, Linckia sea stars
appear very active, moving about and grazing the bottom
for food. But even more curiously,
they’re polite, restraining
from walking on top of each
other. Like bumper cars, when one
Linckia touches another, they
each go the other direction. It’s all very civilized. In an hour, a Linckia on the
move can travel several car
lengths. Sea stars are amazing animals.
They might look like they are
just sitting there doing nothing, but they survive by
hunting for food, and they do
that in many ways from catching it as it floats by… to
chasing it down. They’re such
good predators that sometimes they can destroy entire reefs.
It just goes to prove that just
because something is slow, doesn’t mean it isn’t up to
something. You never know where
a sea star is going to turn up! ( ♪ music )

100 thoughts on “Sea Stars | JONATHAN BIRD’S BLUE WORLD

  1. crown of thorns. their for a reason people just kill them also maybe starving their predator coral new growth. helps alot

  2. There's a starfish in your head

  3. Loved that seastar sitting on your head in the end of the video… great video presentation and your narration is superb Jonathan Bird

  4. 6:11 Sea Cucumber: I'm Scared
    Starfish: I'm am going to eat you Sea Cucumber
    Sea Cucumber: I'm right hear
    Starfish:ok😠😠😠😠
    Sea Cucumber:Crying😢😭
    Starfish:Sorry
    Sea Cucumber:It Okay😀😀😀

  5. I love your narration sir.. I can clearly understand even I'm not an English tongue.. You really deserve more views and subscribers sir..
    I even downloaded your informative videos for my kids coz we don't have internet in our native place in the Philippines …. Thank you sir..God bless. 😇🐬🐳🐙🐠

  6. Crown of thorns starfish is destroying our coral reef in Philippines. They been eating a lot to the extent they ate an acres of coral reef in one of the islands in Phil.

  7. I remember when I was on the island of Guam I found blue sea stars on the beach and I pick one up and felt it and look on all side of it and when I was contented with it I threw it like a ninja star in a way that it had the most amazing fun as it spun and floated through the air and back into the water.

    I still wonder if it had learned from that moment and created more babies of its kind.

    I appreciate your time you take to edit your videos and say good things we all need to hear and experience.
    Presentation shows the time away from the water too….
    Thank you so much.
    Your my favorite diving guy I know of.

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