Female red crabs
can lay up to 100,000 eggs
at once.
Red crabs
are native to Australia's
Christmas Island.
After the first rainfall
of the wet season,
millions of them
flock from their homes
in the rainforest
to the shoreline.
Red crabs always spawn
before dawn.
They wait for a
receding high tide
during the last quarter
of the Moon.
When the Moon reaches
its last quarter,
they gather on the shoreline
and release their
thousands of eggs
into the sea.
Aw, they grow up so fast.
Japanese spider crabs
can live to 100 years old.
These geriatric giants
live on the seafloor
along the Pacific Coast
of Japan.
They are the biggest crab
in the world.
They can have legs
4 m (13 ft) long
and weigh up to
20 kg (44 lb).
Their size could account
for their long life span.
And I’m sure
Japanese spider crabs
are wise beyond their years.
Crabs can amputate
their own limbs.
That might sound masochistic,
but it’s actually
a method of self-defense.
When a crab is attacked,
they have a
reflexive response
to injury called autotomy.
The injured limb
separates from the body,
allowing the crab
a quick getaway
from the predator.
Luckily, the severed limbs
can regenerate.
Now that’s what I call
self-growth.
In a 2009 study,
researchers from
Queen’s University in Belfast
made a shocking discovery.
Hermit crabs
who received electric shocks
to their shells
quickly packed up
and moved to a new shell.
They were also found
to rub the spot
that was shocked,
suggesting they remembered
and continued to feel the pain.
Ouch.
When baby crabs
hatch in the water,
they emerge as zoeae.
These transparent larvae
only have a dorsal spine
and a pair of large eyes.
The time spent
in the larval stage
varies from a few weeks
to over a year,
depending on the species.
For terrestrial crabs,
larval life tends to be shorter.
But the Dungeness crab,
native to Alaska,
spends its whole first year
on Earth as a little larva.
Pea crabs
could be an
unwanted dinner guest.
Next time you’re at a
fancy restaurant
cracking open an oyster,
you might want to check
for this little guy.
Pea crabs live in the
mouth of bivalve mollusks
like oysters.
They feed off the oxygen,
plankton and mucus
from their host.
Ah, home sweet home.
But these crabs
But these crabs wreak havoc
on the shellfish industry.
Mussels that host pea crabs
have to be tossed out,
resulting in the loss of
billions of dollars.
Horseshoe crabs
are instrumental
to vaccine development.
Despite their name,
horseshoe crabs
aren’t technically crabs
or even crustaceans
for that matter.
Their closest relatives are
spiders and other arachnids.
But considering
their importance
in the medical world
and the fact
we're running out of them,
we think they deserve
the spotlight.
The horseshoe crab’s
milky-blue blood
is the only natural source
of limulus amebocyte lysate.
This substance detects
a contaminant
called endotoxin.
If even a trace amount
of endotoxin is found
in vaccines or
other sterile pharmaceuticals,
it can be deadly.
Every year,
half a million
Atlantic horseshoe crabs
are rounded up,
bled and
returned to the ocean.
Many of the crabs
die after this.
And with an already
dwindling population,
it might be best to leave
horseshoe crabs alone.
If you want to learn more
about how horseshoe crabs
are integral
to the health industry,
check out our video
that dives into all the details.
Amputating their own limbs
and surviving
in diverse environments
is what crabs do.
And that’s what makes them
Crazy Creatures.