Mulga Snake

## Description

The king brown snake (Pseudechis australis ) is a species of highly venomous snake of the family Elapidae, native to northern, western, and Central Australia. Despite its common name, it is a member of the genus Pseudechis (black snakes) and only distantly related to true brown snakes. Its alternative common name is the mulga snake, although it lives in many habitats apart from mulga. First described by English zoologist John Edward Gray in 1842, it is a robust snake up to 3.3 m (11 ft) long. It is variable in appearance, with individuals from northern Australia having tan upper parts, while those from southern Australia are dark brown to blackish. Sometimes, it is seen in a reddish-green texture. The dorsal scales are two-toned, sometimes giving the snake a patterned appearance. Its underside is cream or white, often with orange splotches. The species is oviparous. The snake is considered to be a least-concern species according to the International Union for Conservation of Nature, though may have declined with the spread of the cane toad.

Its venom is not as potent as those of Australia's other dangerous snakes, but can still cause severe effects if delivered in large enough quantities. Its main effect is on striated muscle tissue, causing paralysis from muscle damage, and also commonly affects blood clotting (coagulopathy). Often, extensive pain and swelling occur, rarely with necrosis, at the bite site. Deaths from its bites have been recorded, with the most recent being in 1969. Its victims are treated with black snake (not brown snake) antivenom.

## Appearance

The Mulga snake is a highly venomous snake native to Australia. This is a robust snake, with a head slightly wider than the body, prominent cheeks and small eyes with red-brown irises, and a dark tongue. Scales on the upper-parts, flanks, and tail are two toned-pale or greenish-yellow at the base and various shades of tan or copper, or all shades of brown from pale to blackish towards the rear. This gives the snake a reticulated pattern. The tail is often darker, while the crown is the same color as the body. The belly is cream, white or salmon and can have orange marks. The colors of the snakes' upper-parts and sides differ from area to area within their range; those from northern Australia are tan, those from deserts in Central Australia have prominent white marks on each scale, giving a patterned appearance, and those from southern parts of its range are even blackish. In Western Australia, Mulga snakes are significantly darker in color.

## Distribution

Mulga snakes are found in northern, western, and Central Australia. They occur in all states of Australia except for Victoria and Tasmania. The eastern limit of their range runs from Gladstone in central Queensland, and south through Gayndah, Dalby, the Warrumbungles, southwest to Condobolin and the vicinity of Balranald and then across to Port Pirie in South Australia. The southwestern limit of their range runs from Ceduna in South Australia, west through the northern Nullarbor Plain to Kalgoorlie, Narrogin and on coastal plains north of Perth. Mulga snakes live in rainforests, woodlands, hummock grasslands, chenopod scrublands, and gibber or sandy deserts nearly devoid of vegetation. Within the arid to semi-arid parts of their range, however, they prefer areas of greater moisture such as watercourses. They are often observed at modified habitats such as wheat fields, rubbish piles, and vacated buildings.

## Behavior

Mulga snakes lead a solitary life. They are mostly crepuscular-active at dusk, and are less active during the middle of the day and between midnight and dawn, retiring to crevices in the soil, old animal burrows, or under rocks or logs. During warmer months their activity shifts to later after dusk and into the evening. In cooler climates of their range they are more active during the day and in hotter climates-at night.The king brown snake accounted for 4% of identified snakebite attacks in Australia between 2005 and 2015, with no deaths recorded. The last recorded death occurred in 1969, when a 20-year-old man was bitten while reaching around for a packet of cigarettes under his bed in Three Springs, Western Australia. The man was treated over two days, with twice daily injections of death adder, brown snake and tiger snake antivenin, yet died in 37 hours despite this medical attention. This incident led to the introduction of Papuan black snake antivenom for treatment of king brown snake envenomation. Before this it had been confirmed in one fatality and suspected in another in the early 1960s. Venomous snakes normally only bite humans when disturbed. King brown snakes have been noted, however, to bite people who were asleep at the time. Furthermore, a significant number of victims have been snake handlers. These have resulted in a high proportion of bites occurring on upper limbs. The king brown snake is classified as a snake of medical importance by the World Health Organization.

## Diet

Mulga snakes are carnivorous reptiles. They feed on lizards including small monitors, skinks, geckos and agamids, other snakes including whip snakes, brown snakes, the brown tree snake, southern shovel-nosed snake, Gould's hooded snake and crowned snake, birds such as thornbills, small mammals such as rodents and dasyurids, and frogs. They may eat roadkill and are known to exhibit cannibalism.

## Reproduction

The mating season for Mulga snakes begins in the early Southern Hemisphere spring in southwest Western Australia, mid-spring in the Eyre Peninsula and with the Wet Season in the north of the country. Males engage in wrestling combat, each attempting to push the other over for the right to mate with a female. Females produce a clutch of 4 to 19 eggs, generally 39-45 days after the mating. Eggs are incubated for about 70 to 100 days. Baby snakes are 22.6 cm (9 in) in length and weigh 9.4 g (0.33 oz) on hatching.

## Population

### Population threats

There are no major threats facing Mulga snakes at present. However, populations of this species in some areas of their range may have declined with the spread of the Cane toad. Mulga snakes are sensitive to Cane toad toxins and die after eating them.

### Population number

The IUCN Red List and other sources don’t provide the number of the Mulga snake total population size. Currently, this species is classified as Least Concern (LC) on the IUCN Red List but its numbers today are decreasing.