A brave crab launches itself into certain danger.
A leap of faith.
It will walk on water to escape what lies below.
In these tranquil rock pools, hungry creatures lurk,
waiting for the Sally Lightfoot crab to make just one wrong step.
Waves pound Brazil's Atlantic coast like sledgehammers.
When a Sally Lightfoot crab sees them coming,
it clings onto the slippery rocks
and flattens itself, so the water just slides off its shell.
A brief pause in feeding on the algae and seaweed
found along the shore at low tide.
Until the next set of waves hits.
Seaweed and algae aren't their only food.
They'll eat whatever they come across,
including baby birds and even other crabs.
But they themselves are eaten too.
Many of their predators come in on the high tide,
then hide in the rock pools to wait it out.
To escape them,
Sally Lightfoot crab retreat when the tide comes in.
They hold water in their shells to survive on land.
While they're high and dry on the rocks,
they pour it over their gills to keep breathing.
It's a crucial adoption
because most of their time is spent above the water
waiting for the tides to change.
The turn from high to low
signals that it's time to return to the feeding grounds.
But it's not just a matter of walking across rocks.
Sally Lightfoot crabs may even have to walk on water
right above the predators that came in with the sea,
some with arms and some without.
They all find this fleshy crab irresistible,
a meal worth waiting for.
But the Sally Lightfoot is a clever crab.
They seem to be able to read their predators minds
and only launch themselves when the coast is clear.
One predator is even more intelligent.
The octopus leaves the water to stalk on eight arms.
Arms that seem specially adapted for catching crabs.
The imperative to eat outweighs the risk.
Each crab will have to dive into certain danger
to reach the banks of seaweed and algae,
a moray eel speeds towards the action,
smelling its prey.
The crab's movements across the water lure the octopus.
It changes color to blend with the rocks.
But the eel needs to find a hidden place
from which to launch its surprise attack.
It's now that the Sally Lightfoot shows how it may have got its name.
To escape its predators,
it tries to touch the surface of the water as little as possible.
Concealed and ready to attack,
the eel is also preparing to leap.
The younger crabs have much softer shells than the adults,
so they are more at risk.
Losing one leg is no problem.
It will grow back.
But this crab is about to lose all six.
First, the octopus will inject a paralyzing saliva.
Without the teeth of an eel to crack the shell,
the octopus dismembers with its beak
very efficiently.
Many Sally Lightfoot crabs have made it to the feeding grounds.
It will take another six hours for the tide to cycle from low to high.
Until then, the crabs will face the power of the waves again.
Were you swept away by this talented animal?
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