The Banded krait (Bungarus fasciatus) is the largest species of kraits, with a maximum length up to 2.7 m (8 ft 10 in).
Although the banded krait is venomous and its bite may be deadly to humans, it is shy, primarily nocturnal, and not particularly aggressive so its overall risk to humans is low.
The Banded krait is easily identified by its alternate black and yellow crossbands, its triangular body cross-section, and the marked vertebral ridge consisting of enlarged vertebral shields along its body. The head is broad and depressed. The eyes are black. It has arrowhead-like yellow markings on its otherwise black head and has yellow lips, lores, chin, and throat.
Banded kraits occur in the whole of the Indo-Chinese subregion, the Malay peninsula and Indonesian archipelago, and southern China. These snakes have been recorded eastwards from central India through Bangladesh, Myanmar, Cambodia, Thailand, Laos, Vietnam, and southern China (including Hong Kong) to Malaysia and the main Indonesian islands of Borneo (Java and Sumatra), as well as Singapore. Banded kraits may be seen in a variety of habitats, from dry and moist deciduous forests, mangrove vegetation, and tropical scrub to agricultural lands. They inhabit termite mounds and rodent holes close to water, and often live near human settlements, especially villages, because of their supply of rodents and water. They prefer the open plains of the countryside.
Banded kraits are shy, not typically seen, and lead a solitary life. They are mainly nocturnal. During the day, these snakes lie up in grass, pits, or drains. They are most commonly seen in the rain. Banded kraits are lethargic and sluggish even under provocation. When harassed, they will usually hide their heads under their coil and do not generally attempt to bite, though at night they are much more active and widely considered to be more dangerous then.
The venom of the Banded krait mainly contains neurotoxins (pre- and postsynaptic neurotoxins). The quantity of venom delivered averages out at 20-114 mg. The major clinical effects caused by the venom of this species include vomiting, abdominal pain, diarrhea, and dizziness. Severe envenomation can lead to respiratory failure and death may occur due to suffocation. Banded krait venom can damage the kidneys if injected. A clinical toxicology study gives an untreated mortality rate of 1–10%, which may be because contact with humans is rare and when bites do occur, the rate of envenomation when biting defensively is thought to be very low. Currently, polyvalent antivenoms are available in India and Indonesia.
Banded kraits are carnivores and feed mainly on other snakes such as the Sunbeam snake, Rainbow water snake, Red-tailed pipe snake, Indo-Chinese rat snake, Cat snake, and others. However, they may also eat fish, frogs, skinks, and snake eggs.
Little is known about the breeding habits of Banded kraits. Females lay around 4-14 eggs which they incubate and guard until they hatch. These snakes are believed to become adults in the third year of their life, at an approximate length of 914 mm.
The main threats to Banded kraits include persecution and road mortality.
According to IUCN, the Banded krait is locally common and widespread throughout its range but no overall population estimate is available. Currently, this species is classified as Least Concern (LC) on the IUCN Red List and its numbers today are stable.
Banded kraits are often found near human settlements due to the presence of rats, mice, and other rodents and help control their populations. This also benefits the farmers.
