A cannibal crab swarmed by millions of babies snacks on them in a rare video.

The pregnant Christmas Island red crab is seen picking up babies with her claws and popping them into her mouth.

The babies are seen returning from their ocean migration and heading to their jungle home when they are ambushed by the larger crustacean.

Every year 50 million Christmas Island red crabs migrate from the jungle to the coast to spawn their eggs into the sea. Most of the year the crabs live in burrows dug in the jungle. During the dry season they cover up the burrow entrance to keep it humid inside

The large crab is at the beach to lay her eggs, but at the same time a previous spawn of babies is returning.

It's claws are unequal in size since one has regrown after being severed.

Every year 50 million Christmas Island red crabs migrate from the jungle to the coast to spawn their eggs into the sea.

The newly-spawned baby crabs drift around out at sea for the first month of their life and if they are lucky, the currents bring them back to Christmas Island.

How shellfish! The hulking crab is at the beach to spawn her eggs at the same time that a previous spawn of babies is returning. One of its claws is bigger than the other meaning it has regrown a claw after its previous claw was severed

A smaller Christmas Island red crab scuttles across the beach on Christmas Island. The crustaceans reach sexual maturity when they are four to five years old. Their life-span is believed to be 20-30 years based on similar animals

Facts about Christmas Island red crabs A mature Christmas Island red crab Measure up to 11.6 centimetres

Estimated life span of 20-30 years

Reach sexual maturity at 4-5 years

Male crabs are larger

Females have a broader abdomen

Claws are usually equal size

Unequal claws occur when one claw is severed and the limb regrows Advertisement

Mature crabs migrate to the beach from October to December at the start of the wet season.

They can only spawn their eggs once a month in time with the tides and a special phase of the moon.

This can overlap with the previous months' babies returning, allowing opportunistic crabs to chow down on infants.

Most of the year the crabs live in burrows dug in the jungle.

During the dry season they cover up the burrow entrance to keep it humid inside.

The next wet season they leave the jungle to start the annual breeding cycle.

Male crabs arrive at the beach first and dig burrows which they defend from other males.

Females arrive after to spawn their offspring in the burrows and release them when the time is right.

The crustaceans reach sexual maturity when they are four to five years old.

Their life-span is believed to be 20-30 years based on similar animals.

The Christmas Island red crabs live on their namesake island and the Cocos Islands.

An estimated 43 million crabs live on Christmas Island alone.

Introduced yellow crazy ants have killed 10–15 million red crabs in recent years.