King Cobra

Quick Take

• The king cobra's reputation as a deadly aggressor hides a personality trait most people would never expect. Explore its shy nature →
• Its venom has quietly made its way into your medicine cabinet, though not in the way you'd think. See venom in medicine →
• One behavior sets the king cobra completely apart from every other snake species on Earth. Discover nest-building behavior →
• A king cobra hatchling is born with something that even adult snakes take years to develop, and this trait makes them immediately dangerous. See hatchling traits →

King cobras measure an average of 10 to 12 feet long. They live in southern China, India, and southeastern Asia. Their habitat includes streams, forests, bamboo thickets, and swamps. This snake is a carnivore eating other snakes, birds, and lizards. King cobras live about 20 years in the wild.

Incredible King Cobra Facts

• It’s the only snake that builds a nest for its eggs.
• They have enough venom in their bite to kill an elephant.
• This reptile raises the top third of its body and expands its hood when it feels endangered.
• Humans and mongooses are among the primary predators of King Cobras, with mongooses known to actively hunt and kill them.
• King cobras are the largest venomous snake. The largest king cobra ever measured, according to Guinness World Records, was 5.71 metres (18 ft 9 in) and was recorded at the London Zoo in 1939.

History and Evolution

Cobras and the King Cobra evolved to have a hooded neck and head area. This protuberance is an expansion of the snake’s ribcage. These ribs are also able to pull outward the King Cobra’s excess skin in this area. It is believed that these deadly snakes adapted this feature in order to appear larger and more fearsome to any would-be threats in the wild. They couple this tactic with a loud and aggressive hiss that is meant to also scare off predators.

Research from scientists on cobra venom has actually led to the production of medicine, namely Cobroxin, that functions as a painkiller. Particularly, they are being used to stop transmission from nerves and even severe arthritis. Due to successful ventures in this type of research, there is ongoing testing and development of medicine derived from snake toxins.

Classification and Scientific Name

A king cobra’s scientific name is Ophiophagus hannah. The Greek word Ophiophagus means snake-eater, and hannah is believed to reference the hamadryad, a tree-dwelling wood nymph from Greek mythology. The king cobra eats other snakes and lives a lot of its life in trees. It sometimes goes by the name hamadryad. It belongs to the Elapidae family and is in the Reptilia class.

New research shows that king cobras across Asia are actually four entirely distinct Ophiophagus species, not one. A 2024 study confirmed these independently evolved lineages, overturning the long-held assumption that all king cobras belong to a single species.

There are 20 different related species of cobra, including the forest cobra, the Ashe’s spitting cobra, the Mozambique cobra, and the Indian cobra. These are part of the Naja genus, or “true cobras.”

Appearance

A king cobra is an animal with a smooth body that is covered in yellow, brown, green, and black scales. It has a chevron pattern of color running down the back of its neck. Some king cobras are leucistic. A leucistic king cobra is missing most of its coloration and looks white. It’s not an albino because it has blue eyes as opposed to pink ones. A leucistic king cobra has all the qualities of a king cobra with the exception of its black, green, brown, and yellow scales.

King cobras are animals that have two dark eyes and fangs that are a half-inch long. A half-inch may sound very short for a snake’s fangs. But they have to be short, so they won’t press through its lower jaw when it closes its mouth.

This snake can measure 12 to 18 feet long. As an example, an 18-foot-long king cobra is equal in length to 2/3 of a London bus. Compare this to the forest cobra, which typically grows to around 4.6 to 7.2 feet long, though some can reach up to 12 feet or more. No wonder the king cobra is known as the longest venomous snake in the world.

The king cobra weighs between 11 and 20 lbs. A 20 lb king cobra is equal in weight to two gallons of paint. The heaviest king cobra lived in the New York Zoological Park and weighed 28 lbs. Male king cobras grow to be a little bigger than females.

Behavior

Though this snake is known for being aggressive, it has a shy nature. It would rather steer clear of people and other animals, if possible. It’s considered a solitary reptile. However, the group is called a quiver when they are seen together during the breeding season.

This reptile’s dark brown, green, and black scales allow it to blend in with its environment. However, when it feels threatened by an animal or human, it will expand its hood and raise the top half of its body off the ground. This is so it can move freely and meet the eye of whatever is threatening it. Also, this snake shows its fangs and hisses at the threat. Some people say that a king cobra’s hiss sounds a lot like a dog’s growl.

The defensive stance of a king cobra is a big part of the reason why they are considered to be aggressive reptiles. However, these reptiles are simply defending themselves from threats.

The venom of a king cobra is not the strongest of all snakes, but the amount of venom it can inject into a person or animal in one bite is enough to kill an elephant or 20 people. The venom causes respiratory distress and cardiac failure.

Habitat

King cobras live in parts of Southeast Asia, southern China, and India. Their habitat includes forests, bamboo thickets, streams, and swamps. These snakes live in a warm, humid climate.

They spend most of their time in trees, blending into the dense, leaf-filled branches. They sometimes hang down from a tree branch to capture another snake. Other times, king cobras come down from the trees to hunt for prey on the forest floor. They may travel to nearby streams to look for food. These reptiles can swim fairly well and have been seen moving along through the water.

When the weather cools off in late fall and winter, king cobras migrate to dens to stay warm. They come back out in the springtime.

Diet

What do king cobras eat? King cobras are carnivores eating birds, lizards, and other snakes. When those are scarce, these snakes will eat small rodents. If a king cobra eats a large amount of prey at one time, it may not eat again for a few months.

This snake has excellent eyesight. It can sometimes spot prey while resting on a high branch in a tree. Like other snakes, it also has an impressive sense of smell.

King cobras are fast and move quickly to strike their prey without having to hold it in place like other cobras.

Predators and Threats

Poachers sometimes set traps for these snakes and kill them for their skin, to make medicine, or even to eat. Some of these reptiles are sold illegally as exotic pets.

However, humans are not the only predators of the king cobra. Mongooses, honey badgers, and secretary birds also prey on them. The mongoose is immune to small amounts of their venom, but they really win the fight using their speed and agility.

Since these reptiles need a certain type of environment to thrive and they have a venom that is capable of killing a human, it’s definitely not a good idea for anyone to keep one as a pet.

In Southeast Asia, snake charmers sometimes use king cobras in their street performances. They pretend like the king cobra is charmed by the music they’re playing on the flute. These snakes have been known to bite snake charmers as well as escape into an environment where they can’t survive.

Habitat loss due to deforestation and land clearing is another threat to king cobras.

The official conservation status of king cobras is Vulnerable, with a decreasing population. Though they are on the endangered list of species in India, this country is taking steps to protect them. They are focusing on properly educating the public about these reptiles. Plus, they are also microchipping king cobras so they can track them if they are captured by exotic pet dealers. Vietnam has given these snakes protected species status.

Reproduction and Life Cycle

The breeding season of a king cobra goes from January to April. When a male king cobra is interested in a female, it pushes her body with its head. If other male king cobras are in the area, the males wrestle, and the strongest one mates with the female. King cobras are monogamous (stay with the same mate each breeding season).

The female creates a nest by pushing twigs, grass, and other vegetation into a pile. The temperature within the pile/nest is around 80 degrees Fahrenheit. Shortly after, she lays 21 to 40 (sometimes more) eggs in the nest. The eggs hatch between 51 and 79 days later. As a note, the king cobra is the only snake that builds a nest for its eggs. The female stays with the nest and fiercely guards her eggs from predators until they hatch. Consequently, most of the king cobra eggs will hatch, and the babies will survive.

Baby king cobras are called hatchlings. Each hatchling can weigh from less than an ounce to one and a half ounces. The hatchlings usually measure from 12 to 29 inches long. A 12-inch-long hatchling is equal to the size of a small wooden ruler.

The hatchlings are brightly colored. This helps to scare off predators. As they grow, their scales turn dark brown, black, and green. They leave the nest to hunt prey and live independently right after hatching. The venom of a hatchling is every bit as powerful as an adult king cobra. Keep that in mind in case you ever see one.

These reptiles are vulnerable to various types of skin fungi. The lifespan of a king cobra in the wild is around 20 years. But the oldest king cobra record is held by a snake that reached 22 years of age.

Population

The exact population of king cobras is unknown. However, the conservation status of the king cobra is Vulnerable. Its population is decreasing. Loss of habitat and poaching activity are two major threats to the population of this snake. It’s on the endangered species list in India.