Fig. 4.54  Bungarus caeruleus.

Distribution

Southeastern Iran and Afgahnistan, Indian subcontinent, Southeast Asia and China. See link "Distribution" at the top of the page for detailed information.

  Map 24 Bungarus spp.

Biology

Slender but not graceful snakes with an oval-shaped head. The head is comparatively small and slightly distinct from the neck. The venom fangs are relatively short. In cross-section, the body is triangular, tapering towards the spine. Scales over the spine are typically large and hexagonal (with the exception of B. lividus). In B. fasciatus, the tip of the tail is blunt. Smaller species average 70 and 90 cm in length (B. sindanus, B. ceylonicus). B. flaviceps and B. fasciatus can reach up to 2 m.

B. flaviceps is blue-black in colour, with a red head and red tail, B. fasciatus has black and yellow bands. B. candidus has wide black and white bands. The basic colouring of B. caeruleus is dark and shiny with fine, light cross bands (sometimes fading), as for B. ceylonicus, but its cross bands are widely spaced. B. multicinctus, B. candidus, B. wanghaotingi, B.suzehenae and B. sagittatus show distinct pale cross bands on dark ground, merging on the underside.  

Habitats: B. caerulaeus and B. sindanus are found in open, dry areas and agricultural areas. B. ceylonicus lives in cooler, damper, wooded or agricultural regions. B. multicinctus is found in forests, grasslands and rice fields. B. fasciatus, a common species, lives in damp, wooded and open areas and cultivated regions. B. flaviceps is an uncommon species and lives in dense jungle in higher locations. B. caeruleus, B. candidus, B. sindanus and B. multicinctus are often found close to settlements and on the outskirts of cities.

Kraits feed on cold-blooded animals, in particular other snakes. They have a tendency to live in rodent burrows or termite mounds, but they will also shelter in piles of rubbish close to houses.

They are strictly nocturnal. During the day they are shy, hardly ever seen and practically never strike, even under severe provocation (it's still wise to be cautious though!). Instead of retreating, they hide their head under the coils of their body. In contrast, in their active nocturnal phase, during which B. caeruleus in particular will often enter human habitations in search of prey, they are extremely agile and will strike at the slightest provocation.  

Risk

Dangerous venomous snakes. Systemic envenoming is not uncommon. Practically all accidents occur at night, chiefly in living areas while the victim is asleep on the floor (Theakston et al. 1990). The bite often goes unnoticed and the victim awakes with neurotoxic symptoms.

In India, B. caeruleus is the most important krait in medical terms. In West Bengal, it is estimated that approximately a third of all venomous snakebites are caused by this species (Hati 1983). In Sri Lanka, B. caeruleus and B. ceylonicus are responsible for almost 10% of reported bites and 17% of snakebite fatalities (De Silva and Ranasinghe 1983).

In Thailand, B. candidus – and not B. fasciatus as previously thought – together with Calloselasma rhodostoma und Naja naja spp. is the cause of most fatalities (Looareesuwan et al. 1988). In Myanmar, the rate of accidents with B. fasciatus seems to be very low (Aye 1990).

Literature (biological)

Abtin et al. 2014, Aksornneam 2024, Chen et al 2021, Cox 1991, Daniel 1983, Deoras 1971, 1983, De Silva 1990, Deuve 1970, Khan 1985, 1990, Kuch and Mebs 2007, Kuch et al. 2005, Liat 1979, Murthy 1990, Saint Girons 1972, Slowinski 1994, Theophilus et al. 2008, Tweedie 1983, Zhao 1990, Oshea 2005

www.reptile-database.org