The Vampire Squid Is Not a Vampire — It Eats the Ocean's Falling Waste

The Name Is Almost Completely Wrong

Vampyroteuthis infernalis.

Translated from Latin, the name is often given as "vampire squid from hell."

It sounds like an animal designed to hunt in darkness.

The creature has dark reddish skin.

Its eight arms are connected by a cloak-like web.

When threatened, it can pull this web over its body, exposing rows of fleshy spines.

It lives hundreds of metres beneath the ocean surface, far beyond ordinary sunlight.

There is only one problem with the terrifying image.

The vampire squid is not a blood-drinking monster.

It is not even an aggressive hunter in the way its name suggests.

Much of its food is rubbish falling through the ocean.

It Lives Where Other Cephalopods Struggle

Deep in the ocean are regions where dissolved oxygen becomes extremely low.

These are known as oxygen minimum zones.

For active animals, low oxygen creates a serious problem.

Fast swimming requires energy.

Energy production requires oxygen.

Squid are usually active predators, built to chase and capture living prey.

The vampire squid took a different evolutionary path.

Its metabolism is remarkably low, and its body is adapted to survive in oxygen conditions that would be extremely difficult for many other cephalopods.

Instead of spending its life racing after prey, it can drift through the darkness and wait for food to come down from above.

And food is always falling.

The Ocean Has Snow

Scientists call it marine snow.

It is not frozen water.

Marine snow is a constant shower of organic material sinking from the upper ocean.

Dead microscopic organisms fall.

Tiny pieces of animals descend.

Faecal pellets sink through the water.

Mucus and discarded structures produced by gelatinous animals join the slow-moving rain.

Particle by particle, material from life near the surface travels into the deep sea.

To us, it may sound like waste.

To a vampire squid, it is dinner.

Two Living Fishing Lines

For years, the feeding behaviour of the vampire squid puzzled scientists.

Its body did not seem designed for active hunting.

Then observations from remotely operated vehicles and laboratory studies revealed something extraordinary.

The vampire squid has two long, thin, retractable filaments.

These filaments can extend far beyond the body.

Rather than attacking prey, the animal allows a filament to drift through the water.

Sticky and sensitive surfaces collect particles of marine snow.

When enough material gathers, the vampire squid draws the filament back.

The collected debris is mixed with mucus produced by suckers on the arms.

Small finger-like structures called cirri help move the food towards the mouth.

The terrifying "vampire from hell" is carefully making a ball of ocean debris and eating it.

Researchers described this feeding strategy as unlike that of any other living cephalopod known at the time of the study.

Why Waste Is a Brilliant Food

At first, eating marine snow sounds like a poor survival strategy.

But look at the vampire squid's home.

The deep ocean is dark.

Oxygen is limited.

Living prey can be scarce.

Chasing another animal would use valuable energy, and the chase might fail.

Marine snow has one enormous advantage.

It does not run away.

The vampire squid's low-energy lifestyle and unusual feeding filaments allow it to collect food while avoiding the enormous energy costs of constant hunting.

Evolution did not make the vampire squid weak.

It made the animal economical.

Its Defence Is Stranger Than Ink

Most people associate squid with clouds of dark ink.

But in the deep sea, black ink is less useful.

There is already very little light.

The vampire squid has another trick.

It can produce bioluminescent material.

When seriously disturbed, the animal can release glowing particles in mucus.

In the darkness, this creates a confusing display of light.

The vampire squid can also use light-producing organs on its body.

A predator expecting an easy meal may suddenly face flashes and glowing material in a world where light itself is unusual.

The goal is not to win a fight.

The goal is to create enough confusion to escape.

The Cloak of the Vampire Squid

Its most famous defensive posture looks genuinely bizarre.

When threatened, the vampire squid can turn its webbed arms back over its body.

This behaviour is often called the "pineapple posture."

The underside of the arms carries rows of cirri that can resemble threatening spines.

Its vulnerable head and body become partly covered while the strange-looking arm surface faces outward.

The animal suddenly appears larger, darker and much less inviting.

The spines are not the weapons people often imagine.

The display is largely defensive theatre.

In the deep sea, looking difficult to eat may be enough.

A Creature Built Around Saving Energy

Almost every famous feature of the vampire squid makes more sense when viewed through one idea:

Do not waste energy.

It lives in cold, low-oxygen water.

It has a low metabolic rate.

It does not need to constantly chase fast prey.

Its feeding filaments collect falling material.

Its defensive strategies focus on confusion and deterrence rather than prolonged combat.

The vampire squid is not the demon its name promises.

It is something scientifically more interesting.

It is an animal shaped by scarcity.

The Truth Was Better Than the Monster

Humans gave the vampire squid a dramatic name because of its appearance.

Dark colour.

Red eyes.

A webbed cloak.

A life in permanent darkness.

But names can hide an animal as easily as darkness can.

For years, the vampire squid's feeding habits remained poorly understood.

Only by watching it in its natural environment and studying its anatomy did researchers uncover the stranger truth.

Far below the surface, a creature named "the vampire squid from hell" quietly extends a filament into the black water.

Dead plankton falls.

Waste falls.

Mucus falls.

The filament gathers it.

And the vampire eats snow.

Sources: Monterey Bay Aquarium Research Institute (MBARI), Proceedings of the Royal Society B, Monterey Bay Aquarium