The king cobra (Ophiophagus hannah) is a snake known for its deadly venom and impressive size. It's not truly a cobra (genus Naja), although both species belong to the famiy Elapidae, which includes venomous cobras, sea snakes, kraits, mambas, and adders. Its genus name, Ophiophagus, means "snake eater." It is the "king" because it eats other snakes.
Fast Facts: King Cobra
- Scientific Name: Ophiophagus hannah
- Common Names: King cobra, hamadryad
- Basic Animal Group: Reptile
- Size: 10-13 feet
- Weight: 13 pounds
- Lifespan: 20 years
- Diet: Carnivore
- Habitat: India and Southeast Asia
- Population: Decreasing
- Conservation Status: Vulnerable
The king cobra is the world's longest venomous snake. Adults typically measure 10.4 to 13.1 feet in length, but one individual measured 19.2 feet. King cobras are dimorphic in size with males larger than females (the reverse of most snake species). The average adult of either sex weighs about 13 pounds, with the heaviest recorded individual weighing 28 pounds.
The snake is brown or deep olive green with black and either yellow or white crossbands. Its belly is cream-colored or yellow. King cobras can be distinguished from true cobras by its two large scales on the top back of the head and chevron neck stripes instead of "eyes."
Habitat and Distribution
King cobras live in India, Southeast Asia, and southern East Asia. The snake prefers forests near lakes or streams.
Diet and Behavior
A king cobra hunts using its eyes and tongue. Because it relies on keen eyesight, it is most active during the daytime. The snake's forked tongue senses vibration and transfers chemical information to the Jacobson's organ in the snake's mouth so it can smell/taste its surroundings. King cobras primarily eat other snakes, but will take lizards, rodents, and birds if necessary.
When the snake is threatened, it tries to escape. If cornered, it rears its head and the top third of its body, extends its hood, and hisses. A king cobra's hiss is lower in frequency than that of most snakes and sounds like a growl. Cobras in threat posture can still move forward and may deliver multiple bites in a single strike.
Reproduction and Offspring
King cobras breed between January and April. Males wrestle each other to compete for females. After mating, the female lays between 21 and 40 leathery white eggs. She pushes leaves into a pile over the nest so that decomposition provides heat to incubate the eggs. The male remains close to the nest to help guard it, while the female stays with the eggs. While normally not aggressive, cobras readily defend their nests. The eggs hatch in autumn. Juveniles are black with yellow bands, resembling a banded sea krait.
Adults leave the nest after the eggs hatch, but may mate for life. The average life span of a king cobra is 20 years.
The IUCN classifies the king cobra conservation status as "vulnerable." While it's difficult to gauge the number of remaining snakes, the population is decreasing in size. King cobras are threatened by habitat loss from deforestation and are heavily harvested for skin, meat, traditional medicine, and the exotic pet trade. As venomous snakes, cobras are often killed out of fear.
King Cobras and Humans
King cobras are well known for use by snake charmers. Cobra bites are extremely rare, but most cases of bites involve snake charmers. King cobra venom is neurotoxic, plus it contains digestive enzymes. The venom can kill a human within 30 minutes or even an adult elephant within a matter of hours. In humans, symptoms include severe pain and blurred vision which progresses to drowsiness, paralysis, and ultimately coma, cardiovascular collapse, and death from respiratory failure. Two types of antivenom are produced, but they are not widely available. Thai snake charmers drink a mixture of alcohol and turmeric. A 2012 clinical study verified turmeric confers significant resistance to cobra venom. The mortality rate for untreated cobra bites ranges from 50 to 60%, implying the snake only delivers venom about half the time it bites.