The Sangchur, commonly known as the Indian Common Krait or simply the Krait, holds a terrifying reputation as one of the deadliest snakes in Pakistan. With a total of 97 snake species in the country, most are harmless, but the “Big Four” venomous snakes—Common Krait, Russell’s Viper, Saw-scaled Viper, and Indian Cobra—pose serious threats. Among these, the Sangchur stands out as the most lethal. Known as the “Silent Killer,” it inflicts bites that are often as mild in sensation as a mosquito sting, yet death can occur within four to six hours due to delayed recognition and treatment. This danger is amplified when bites happen during sleep, a common occurrence due to the snake’s nocturnal nature.
Scientifically named “Bungarus caeruleus” and belonging to the Elapidae family, the Krait is a medium-sized, slender, and vividly colored snake. It usually grows to around three feet in length but can reach up to six feet. Its body is smooth and cylindrical, marked by 40–50 light-colored bands running across a darker upper body, which ranges from bluish-black to dark brown. Males are typically longer than females and feature relatively long tails. Its small, black eyes with round pupils and flat oval head give it a distinct look.
In Pakistan, Kraits inhabit a wide range of environments, from dry plains to elevations of 1,700 meters. They are commonly found in forested regions, swamps, agricultural areas, and human settlements, especially near water sources. They can also be found in unusual hiding spots such as mud mounds, ground cracks, rat holes, and even under piles of bricks. Despite their adaptability, they are rarely seen during the day. While mostly ground-dwelling, Kraits can climb uneven surfaces in pursuit of food or shelter. Their close proximity to human homes increases the likelihood of nighttime encounters.
Their nocturnal activity, especially from dusk to dawn, aligns with their predatory behavior. During daylight, Kraits remain passive and hidden, but at night they become aggressive. When threatened, they flatten and coil their bodies, tucking their heads in, and may raise their tails in a defensive posture. While they can be handled cautiously during the day, at night, they are quick to strike, often with a hiss.
The venom of the Krait is a potent neurotoxin that attacks the central nervous system. Victims may suffer severe abdominal pain, facial spasms, paralysis, and respiratory failure. The venom’s LD50 (lethal dose for 50% of subjects) is only 0.169 mg in mice, yet an average bite releases around 10 mg. The mortality rate from Krait bites is alarmingly high—about 70 to 80%—primarily due to delayed or absent treatment. Since bites often happen while victims are asleep, people may not even realize they’ve been bitten until symptoms are advanced or death occurs.
During the rainy season, Kraits venture out more frequently and may enter homes in search of dry shelter, not salt as folklore suggests, but warm spaces like beds. This underlines the importance of avoiding sleeping on floors in snake-prone areas.
Kraits are carnivorous and feed on other snakes, including blind snakes, cobra hatchlings, and wolf snakes. They also prey on rodents, lizards, frogs, and occasionally insects. This diet positions them as a natural rodent control agent, particularly in rural and agricultural areas.
The breeding season begins in summer. Kraits are oviparous, with females laying 8–12 eggs between March and July, often in leaf piles or soil mounds. The mother stays with the eggs until they hatch, usually within 60 days. The hatchlings are around 25–27 cm in length and resemble adults in appearance. Though not currently endangered, threats such as habitat destruction and illegal poaching for their meat, skin, and venom—used in medical research—pose serious risks. Kraits are also often killed on roads or by those who fear them.
Precautions to avoid snake encounters include maintaining clean surroundings, eliminating rodent populations, sealing holes and drains, turning on lights at night, and avoiding sleeping on floors. In the event of a snakebite, victims should seek immediate medical attention and avoid traditional remedies.
Several factors contribute to the prevalence and lethality of the Sangchur in Pakistan. Its nocturnal nature means it is less likely to be noticed or killed compared to diurnal snakes. Additionally, as a predator of other snakes, it contributes to the decline of competing species, potentially boosting its own numbers. The unpleasant odor it emits when threatened also deters people from capturing or handling it, which aids its survival. As humans encroach on natural habitats, encounters increase, leading to a higher risk of deadly bites.
Understanding and respecting this silent killer is essential. With better awareness, preventative measures, and prompt medical responses, the devastating toll of Krait bites can be reduced.
