10) Western Brown Snake - Pseudonaja Nuchalis
The Western Brown snake, or Gwarder, is a very fast, highly venomous snake native to Australia. Its colour and pattern is rather variable, depending largely on its location. It is most closely related to the Spotted Brown Snake, Speckled Brown Snake, Peninsula Brown Snake, Ingram's Brown Snake, Ringed Brown Snake and Eastern Brown Snake. Some experts assert that the Western Brown's wide variation in appearance and extensive distribution mean that Western Brown species in fact covers multiple related, but separate species
Appearance
The Western Brown snake grows up to 1.5m. Its back can feature shades of orange-brown with flecks and bands, or appear plain. Its belly is cream to orange with pink blotches. Some individuals have jet black heads (this can cause it to be confused with the Black Headed Python), while others feature a black 'V' shape on the back of their neck, below their head.
Habitat
The Western Brown is a ground dwelling snake which is prefers drier habitats but is also found in coastal eucalypt forests, woodlands and grasslands. Although the Western Brown is not an arboreal species, it is not uncommon for it to climb small shrubs or trees. It also hides in crevices and under rocks, and in urban areas can be found under rubbish or tin piles. The Western Brown has a wide distribution and is found across most of the Australian continent, including all of the Northern Territory, as well as most of Queensland, Western Australia, and some of Victoria.
Diet
Small mammals and reptiles, including lizards and mice.
Lifespan and reproduction
Little is known about the Western Brown's lifespan. Mating season is roughly from September to November and the female usually produces around 11-14 eggs, but may produce up to 38.
Venom and Symptoms
Although the Western Brown snake's venom is not the most toxic in the Brown snake genus, its average delivery contains a relatively high quantity of venom and thus the Western Brown snake has high potential to deliver a deadly bite. Its venom contains neurotoxins, nephrotoxins and a procoagulant, although humans are not usually affected by the neurotoxins. The bite is usually painless and difficult to see due to their small fangs. Human symptoms of a Western Brown snake bite are headache, nausea/vomiting, abdominal pain, severe coagulopathy and sometimes, kidney damage. In dogs and cats, paralysis is also likely to occur.
Behaviour
The Western Brown snake is known to be very aggressive when disturbed or threatened but like most snakes, will usually prefer to retreat from danger. It may develop nocturnal habits during the warmer months but is otherwise active during the day and enjoys lots of sunlight. The Western Brown snake has also been known to practise cannibalism, although this is not common. Western Brown snakes kill their prey with a combination of venom and constriction.
9) Death Adder - Acanthophis Antarcticus
The Common Death Adder (Acanthophis antarcticus), is a species of Death Adder native to Australia. It is one of the most venomous land snakes in Australia and the world. Unlike its sister species of Death Adders, the Common Death Adder is common and is not under major threat.
Common Death Adders have broad flattened, triangular heads and thick bodies. Reaching a length of 70-100 centimetres, they are light brown with dull, darker brown-black stripes running horizontally across their bodies. Their fangs are longer than most of Australia’s venomous snakes.
Distribution
The Common Death Adder occurs over much of eastern and coastal southern Australia - Queensland, New South Wales, Victoria and South Australia. It may also be found more scarce in the Northern Territory, Western Australia and the west parts of South Australia, due to its sister species of Death Adders (eg. Desert Adder).
Habitat
Common Death Adders are found in forests, woodlands, grasslands and heaths of the Eastern Coast of Australia. It is a master of camouflage, due to its band stripes, hiding beneath loose leaf litter and debris in woodland, shrubland and grassland.
Diet
Common Death Adders eat small mammals and birds as a primary diet. Unlike other snakes, the Common Death Adder lies in wait for its prey (often for many days) until a meal passes. It covers itself with leaves — making itself inconspicuous — and lies coiled in ambush, twitching its yellowish grub-like tail close to its head as a lure. When an animal approaches to investigate the movement, the death adder quickly strikes, injecting its venom and then waiting for the victim to die before eating it. This ambush hunting makes the death adder more of a threat to humans.
Reproduction
Unlike most snakes, Death Adders produce litters of live young. In the late summer, a female Death Adder will produce a litter of live babies, approximately 10-20, however over 30 young have been recorded in a single litter.
Venom
The Common Death Adder is the world's fifth most venomous snake and probably the fastest of all Australian snakes when it comes to striking a victim. Death Adders are an ambush predator and while other snakes may attempt to flee if a human comes near a Death Adder is unlikely to, increasing the danger if not noticed.
8) Black Tiger Snake - Notechis Ater
Tiger snakes are a type of venomous serpent found in southern regions of Australia, including its coastal islands and Tasmania. These snakes are highly variable in their colour, often banded like those on a tiger, and forms in their regional occurrences. All populations are in the genus Notechis, and their diverse characters have been described in further subdivisions of this group.
A genus of large venomous snake in the family Elapidae restricted to subtropical and temperate regions of Australia. Tiger snakes are a large group of distinct populations, which may be isolated or overlapping, with extreme variance in size and colour. Individuals also show seasonal variation in colour. The total length may be up to 2.1 meters (7 ft). The patterning is darker bands, strongly contrasting or indistinct, which are pale to very dark in colour. Coloration is composed of olive, yellow, orange-brown, or jet-black, the underside of the snake is lighter and yellow or orange. The tiger snake uses venom to dispatch their prey, and may bite an aggressor; they are potentially fatal to humans. Tolerant of low temperatures, the snake may be active on warmer nights.
Tiger snakes give birth to between 12 to 40 live young, an exceptional record was made of 64 from an eastern female.
Tiger snakes are non-aggressive, and will often give warning strikes with a closed mouth. When threatened they will flatten their body and raise their head above the ground in a classic pre-strike stance.
Morphs
The widely dispersed populations (sometimes referred as polymorphs) show some conformity in their descriptions, but these characters may be shared by separate or adjacent groups. Tiger snakes are also identified by the region or island in which the forms occur, which is prefixed to a common name.
The Common tiger snake has a flat blunt head, slightly distinct from a robust body. Body capable of being flattened along entire length when snake is agitated or basking. Average length 0.9 m, maximum length 1.2 m but has been recorded at 2.0 m (or ~6.6 ft). Highly variable in colour, with base colours of brown, grey olive, green with lighter crossbands usually of creamy yellow. Occasionally unbanded specimens are found. Scales appear like overlapping shields, especially around the neck. Ventrals number 140 to 190, subcaudals 35 to 65, mid-body in 17 or 19 rows and the anal scale is single.
The Western tiger snake has a head that is distinct from its robust body, and grows to 2.0 m in length. Dorsally, steel-blue to black with bright yellow bands; unbanded specimens occur. The ventral surface is yellow, tending black towards the tail. Midbody scales are in 17 or 19 rows, ventrals number 140 to 165, subcaudals 36 to 51 (single) and the anal scale is single (rarely divided).
The Chappell Island tiger snake has a blunt head distinct from a robust body. The giant of the tiger snakes species, averaging 1.9 m (over 6 feet) in length. Dorsally, olive-brown to almost black, sometimes with lighter crossbands. The ventral surface is usually lighter in colour. Juveniles are banded. Mid-body scales are in 17 rows; ventrals number 160 to 171, subcaudals 47 to 52 (single), and the anal scale is single. These snakes are quite docile.
The King Island and Tasmanian tiger snakes each have a blunt head distinct from a robust body. Younger snakes may be slimmer and similar to other tiger snakes, eventually growing up to 1.5 m in length. Dorsally, may be jet black, jet black with lighter crossbands, grey with black flecks forming faint bands or an unbanded grey or brown. The ventral surface is usually a lighter colour. Midbody scales are in 19, 17 or sometimes 15 rows, ventrals number 161 to 174, subcaudals 48 to 52 (single) and the anal scale is single. Tasmanian tiger snakes tend to be quiet snakes, probably due to the lower temperature range they inhabit.
The Peninsula tiger snake has a blunt head distinct from a robust body. Averages 1.1 m in length. Roxby Island specimens are much smaller, averaging 0.86 m in length. Dorsally, generally jet black, sometimes with white or cream markings around the lips and chin. On Kangaroo Island, specimens are highly variable in colour, often exibiting banding and uniform brown colours. The ventral surface is dark grey to black, with some specimens on Kangaroo Island even possessing red bellies. The ventral surface becomes much lighter prior to shedding. Juveniles nearly always have banding. Mid-body scales are in 17, 18, 19 and rarely 21 rows, ventrals number 160 to 184, subcaudals 45 to 54 (single) and the anal scale is single.
The subspecies Notechis ater ater, found away from mainland Australia, is typically uniformly black.
As with most snakes, the colours vary widely between individuals and are an unreliable means of identifying subspecies. Accurate identification is best performed with a venom test kit or scale count.
Habitat
Tiger snakes are found in coastal environments, wetlands, and creeks where they often form territories. Areas with an abundance of prey can support large populations. The species' distribution extends from the south of Western Australia through to South Australia, Tasmania, up through Victoria, and New South Wales. Its common habitat includes the coastal areas of Australia.
Taxonomy
The genus Notechis is placed in the family of elapid snakes. There are two widely recognized species of this genus, Notechis scutatus (Peters, 1861) and Notechis ater (Krefft, 1866), which show further variety in their characteristics. Several authors have published revisions or described subspecies of these species.Others consider the names contained by this taxonomic arrangement to be unwarranted, and describe Notechis as a monotypic genus. Various authorities accept some or all the systematics previously applied but most agree that a revision of the genus is needed. Names for these subdivisions include the Western types, appended to both species names as occidentalis (Glauert 1948) The island groups have also been described as subspecies: Chappell Island tiger snake as N. ater serventyi (Warrell, 1963), King Island and Tasmanian tiger snakes subspecies N. ater humphreysi, (Warrell, 1963) and the Peninsula tiger snake N. ater niger( Kinghorn 1921).
Venom
Tiger snakes possess a potent neurotoxin (notexin), coagulants, haemolysins and myotoxins, and rank amongst the deadliest snakes in the world. Symptoms of a bite include localized pain in the foot and neck region, tingling, numbness, and sweating, followed by a fairly rapid onset of breathing difficulties and paralysis. While antivenom is effective, mortality rate for this species is over 60% if not treated.
Treatment is the same for all deadly Australian snakes. The Pressure Immobilization Method (PIM) is used to inhibit the flow of venom through the lymphatic system. Broad thick bandages are applied over the bite, then down and back along the limb to the armpit or groin. The affected limb is then immobilized with a splint. Identification of the venom is possible if traces are left near the wound. You do not need to identify the snake if bitten in Tasmania, however, as the same antivenom is used to treat all Tasmanian snakes' bites. The availability of antivenom has greatly reduced the incidence of fatal tiger snake bites. The number of deaths is now exceeded by the Brown snake.
Conservation
In most states they are protected species, and to kill or injure one incurs a fine of up to $7,500 as well as a jail sentence of 18 months in some states It is also illegal to export a native Australian snake.
7) Tiger Snake - Notechis Scutatus
The tiger snake is a usually timid species which, like most snakes, usually retreats at the approach of a human. They are an interesting snake which despite the name may not have any striping at all.
Description
The Tasmanian tiger Snake has recently been shown to be the the same species as that which occurs on the south-eastern Australian mainland, (Notechis scutatus). The markings are extremely variable and should not be used in isolation to identify snakes. Colours range from jet black, through yellow/orange with grey bands to sandy grey with no bands. There are unconfirmed reports of red-bellied tiger snakes in north-east Tasmania. Typical forms are of a black snake with either no bands or faint yellow to cream bands. Dark olive snakes with yellow bands are fairly common.
Generally the belly is pale yellow, white or grey, the enlarged ventral scales often edged with black. The head is broad and blunt. It can be difficult to distinguish the tiger Snake from the copperhead since sizes, habitat preferences and behaviour overlap somewhat. Tiger snakes have 13 - 19 rows of scales around the middle of the body, the usual number being 17. On the mainland of Tasmania, tiger snakes reach a length of 1 to 1.8 m. The Chappell Island population reaches prodigious lengths -- up to 2.1 m. Male tiger snakes reach a greater size than females and have larger heads.
Ecology
Wide ranging from dry rocky areas, woodlands, to wet marshes and grasslands. Tiger snakes occur in most habitats in Tasmania. They become inactive over winter, retreating into rodent burrows, hollow logs and tree stumps. Groups of as many as 26 juvenile snakes have been found overwintering in the same place. Generally, tiger snakes do not stay in the same place for more than 15 days, males being especially prone to wandering.
Tiger snakes feed mainly on mammals and birds under 300 g in weight. Tiger snakes habitually raid birds nests and have been found climbing trees to a height of 8 m. A good indicator of the presence of a Tiger snake is the alarm calls of small birds such as honeyeaters and thornbills. They also eat other vertebrates including lizards, smaller snakes, frogs and occasionally fish. Juvenile tiger snakes will use constriction to subdue struggling skinks, a principal food of smaller snakes. Adult snakes are also known to use constriction on larger prey as well. Tiger snakes are important predators of introduced rodent pests and readily enter the burrows of mice, rats and even rabbits in search of their quarry. On a number of offshore islands juvenile tiger snakes feed on small lizards, then as they approach maturity the diet switches to muttonbird chicks. Because these resources are limited competition is fierce and the chances of these snakes reaching adulthood is less than one percent. Occasionally tiger snakes will eat carrion.
A slow, careful hunter which may stand its ground if surprised, relying on its impressive threat display for defence. Like most snakes, tiger snakes are first cowards, then bluffers, and only become warriors as a last resort. If threatened a tiger snake will flatten out its neck, raising its head to make itself appear as frightening as possible. If the threat persists, the snake will often feign a strike, producing an explosive hiss or 'bark' at the same time. Like most snakes, tiger snakes will not bite unless provoked.
Breeding
Sexual actvity is sporadic throughout summer and reaches a peak in late January and February. Mating may last for up to 7 hours, the female occasionally dragging the male about. Males don't eat during periods of sexual activity. Females stop eating 3-4 weeks before giving birth. Female litter sizes have been recorded as high as 126 young, and litter size is often related to female body size. Tiger snakes from small islands produce fewer, larger young. Baby tiger snakes when born are 215 - 270 mm in length. Females produce young at best every second year. There is no maternal care amongst Tiger snakes. Tiger snakes do not become more aggressive during the breeding season, but a male snake tracking a female may well have his mind on other things and may be more easily surprised or be in an unfamiliar environment. He may consequently be more nervous if disturbed.
Distribution
Found in most habitats throughout Tasmania and on may of the offshore islands. As well as being found in southeastern mainland Australia tiger snakes have been recorded from the following Islands: Babel Is., Cat Is., Chalky Is., Christmas Is., Flinders Is., Forsyth Is., Great Dog Is., Hunter Is., King Is., Little Green Is., Maria Is., Mount Chappell Is., New Year Is., Seal Rks, and Trefoil Island.
Status
Secure, although some Island populations may decline if offshore activities threaten muttonbird colonies.
Threats
Now legally protected in Tasmania, tiger snakes still face great danger from human activities such as destruction and fragmentation of habitat. Many are needlessly killed on the road when deliberately run over.
Fangs and poison
The highly toxic venom is produced in large amounts. The venom is mainly neurotoxic, affecting the central nervous system, but also causes muscle damage and affects blood clotting. The breakdown of muscle tissue can lead to kidney failure. Information on first aid for snakebite can be found at our Living with Wildlife web pages.
6) Sea Kraits - Laticauda Colubrina
The Colubrine sea krait, banded sea krait or yellow-lipped sea krait Laticauda colubrina is a species of sea snake found in tropical Indo-Pacific oceanic waters.
Description
Ventrals large, one-third to more than half the width of the body; nostrils lateral; nasals separated by internasals; 21-25 longitudinal rows of imbricate scales at midbody; an azygous prefrontal shield usually present; rostral undivided;
Body subcylindrical, only slightly compressed. Rostral higher than broad; an azygous shield separating the prefrontals, sometimes absent; frontal considerably longer than its distance from the end of the snout; 1 pre- and 2 post oculars ; 7-8 supralabials, the 3rd-4th touching the eye temporals 1+2 ; five infralabials in contact with the genials, both pairs of which are usually well developed and in contact with one another, the anterior pair smaller than the posterior ; a double series of elongated scales, the inner series the larger, at the oral margin. Scales in 21-23 rows (rarely 25). Ventrals 213 to 245, about four times as long as broad. Caudals in males 37-47, females 29-35 (Smith 1943:443).
Total length: males 875 mm, females 1420 mm; tail length: males 130 mm, females 145 mm. In colour these snakes are light or dark bluish grey above, yellowish below, with black bands more or less of uniform width throughout or narrowing on the belly (some of them interrupted below). Upper lip yellow. Snout yellow, the colour extending backward on each side of the head on each side of the head above the eye as far as the temporal shields, leaving a dark bar in between. Rest of the head is black.
They are venomous but are not aggressive to divers.
Biology
Banded sea krait are often seen in large numbers in the company of hunting parties of Giant trevally (Caranx ignobilis) and Goatfish. These snakes need to drink freshwater and regularly come onto land
Observation and nesting
Banded sea krait rest and nest on rocky headlands and beaches of Sabah, Borneo. They can be seen in the wild at Pulau Tiga, the tip of Borneo and Mabul island. They are however seen on a many other harder to get to rocky headlands around Sabah. Occasionally they come ashore at Tanjung aru close to Kota Kinabalu. They can be seen in capitivity at the Green Connection Aquarium in Kota KInabalu. The males come ashore early in the evening and wait at the high tide line for the females. Females are much larger and many males will escort and intertwine around a single female.
5) Eastern Tiger Snake
Eastern Tiger Snake is fairly common over it's range being found from southeast Queensland, East coast of New South Wales to the Great Dividing Range into Victoria and the South East of South Australia, throughout the Murray Darling & Riverland (Murray River) and Onkaparringa River following the Belt into the Adelaide Hills, including their various tributary systems.
There are various sub species of tiger snakes coming in a range of colours & markings and may or may not be banded. Colours range from greenish browns, browns, olive, redish brown to black. The pale crossbands may be greenish white, greyish to yellow but some individuals lack any pattern.
Although there are varying sub-species of tiger snake with differing microhabitats, eg; Chappell, Carnac & Garden Islands where the snakes mainly feed on mutton birds or penguins and shelter in their burrows, the Mainland or Eastern Tiger Snakes' preferred habitat is along freshwater lakes, rivers, creeks & swamps etc; sheltering beneath logs, rocks & other surface debris, old tree stumps etc; even any encountered unused burrows.
The diet of the Eastern or Mainland Tiger Snake mainly consists of frogs, tadpoles, fish including eels, lizards, birds that are nestling in low lying shrubs and trees & small mammals, eg; rats & mice. Although this snake is mainly diurnal, it may also be encountered on warm to hot evenings.
The tiger snake generally has litters of between 15 to 30 being live born from January to April, but litters of more than 100, have been recorded. This snake has been recorded as growing up to 2.1mts.
Although Tiger snakes will attempt to flee if disturbed or encountered, they will aggressively defend themselves if they feel cornered or threatened.
The Tiger snake was once known to be responsible for the most number of deaths from snakebite per year in Australia, having a powerfull neurotoxic venom, but today, the brown snake holds this title. This snake must be considered extremely dangerous to man and any suspected snakebite - even from a newborn baby, treated as an emergency & urgent medical assistance sort. Immediate First -Aid needs to be applied (the pressure immobilization technique), transport brought to the victim, preferably an ambulance and transported to the nearest hospital.
Snakebite Prevention is better than cure
leave all snakes alone and if needed call a professional snakecatcher or herpetologist for advice & or assistance if necessary.
4) Daboia Russell's Viper
Common names: Russell's viper,chain viper,Indian Russell's viper and Daboia is a monotypic genus created for a venomous viper species, D. russelii, which is found in Asia throughout the Indian subcontinent, much of Southeast Asia, southern China and Taiwan. Due largely to its irritable nature, it is responsible for more human fatalities than any other venomous snake. Within much of its range, this species is easily the most dangerous viperid snake and a major cause of snakebite injury and mortality. It is a member of the big four venomous snakes in India, which are together responsible for nearly all Indian snakebite fatalities.[10] The species was named in honor of Dr. Patrick Russell (1726–1805), who had earlier described this animal, and the genus after the Hindi name for it, which means "that lies hid", or "the lurker." Two subspecies are currently recognized, including the nominate subspecies described here.
Description
This snake grows to a maximum length of 166 cm (5.5 ft). The average length is about 120 cm (4 ft) on the mainland, although island populations do not attain this size. It is more slenderly built than most other vipers. Ditmars (1937) reported the following dimensions for a "fair sized adult specimen"
The head is flattened, triangular and distinct from the neck. The snout is blunt, rounded and raised. The nostrils are large, in the middle of a large, single nasal scale. The lower edge of the nasal touches the nasorostral. The supranasal has a strong crescent shape and separates the nasal from the nasorostral anteriorly. The rostral is as broad as it is high The crown of the head is covered with irregular, strongly fragmented scales. The supraocular scales are narrow, single, and separated by 6–9 scales across the head. The eyes are large, flecked with yellow or gold, and each is surrounded by 10–15 circumorbital scales. There are 10–12 supralabials, the 4th and 5th of which are significantly larger. The eye is separated from the supralabials by 3–4 rows of suboculars. There are two pairs of chin shields, the front pair of which are notably enlarged. The two maxillary bones support at least two and at the most five or six pairs of fangs at a time: the first are active and the rest replacements. The fangs attain a length of 16 mm in the average specimen.
The body is stout, the cross-section of which is rounded to cylindrical. The dorsal scales are strongly keeled; only the lower row is smooth. Mid-body, the dorsal scales number 27–33. The ventral scales number 153–180. The anal plate is not divided. The tail is short — about 14% of the total body length — with the paired subcaudals numbering 41–68.
The color pattern consists of a deep yellow, tan or brown ground color, with three series of dark brown spots that run the length of its body. Each of these spots has a black ring around it, the outer border of which is intensified with a rim of white or yellow. The dorsal spots, which usually number 23–30, may grow together, while the side spots may break apart. The head has a pair of distinct dark patches, one on each temple, together with a pinkish, salmon or brownish V or X pattern that forms an apex towards the snout. Behind the eye, there is a dark streak, outlined in white, pink or buff. The venter is white, whitish, yellowish or pinkish, often with an irregular scattering of dark spots.
Geographic range
Found in Pakistan, India, Sri Lanka, Bangladesh, Nepal, Myanmar, Thailand, Cambodia, China (Guangxi, Guangdong), Taiwan and Indonesia (Endeh, Flores, east Java, Komodo, Lomblen Islands). The type locality is listed as "India". More specifically, this would be the Coromandel Coast, by inference of Russell (1796).
Brown (1973) mentions that it can also found in Vietnam, Laos and on the Indonesian island of Sumatra. Ditmars (1937) reportedly received a specimen from Sumatra as well. However, the distribution of this species in the Indonesian archipelago is still being elucidated.
Within its range it can be very common in some areas, but scarce in others. In India, is abundant in Punjab, very common along the West Coast and its hills, in southern India and up to Bengal. It is uncommon to rare in the Ganga valley, northern Bengal and Assam. It is prevalent in Myanmar.
Habitat
It is not restricted to any particular habitat, but does tend to avoid dense forests. The snake is mostly found in open, grassy or bushy areas, but may also be found in second growth forests (scrub jungles), on forested plantations and farmland. They are most common in plains, coastal lowlands and hills of suitable habitat. Generally not found at altitude, but has been reported as far up as 2300–3000 m. Humid environments, such as marshes, swamps and rain forests, are avoided.
This species is often found in highly urbanized areas and settlements in the countryside, the attraction being the rodents commensal with man. As a result, those working outside in these areas are most at risk of being bitten. It should be noted, however, that D. russelii does not associate as closely with human habitation as Naja and Bungarus (cobras and kraits).
Behavior
Terrestrial and active primarily as a nocturnal forager. However, during cool weather it will alter its behavior and become more active during the day.Adults are reported to be persistently slow and sluggish unless pushed beyond a certain limit, after which they become fierce and aggressive. Juveniles, on the other hand, are generally more active and will bite with minimal provocation.
When threatened they form a series of S-loops, raise the first third of the body and produce a hiss that is supposedly louder than that of any other snake. When striking from this position, they can exert so much force that even a large individual can lift most of its body off the ground in the process. These are difficult snakes to handle: they are strong and agile and react violently to being picked up. The bite may be a snap, or, they may hang on for many seconds.
Although this genus does not have the heat-sensitive pit organs common to the Crotalinae, it is one of a number of viperines that are apparently able to react to thermal cues, further supporting the notion that they too possess a heat-sensitive organ. The identity of this sensor is not certain, but the nerve endings in the supranasal sac of these snakes resemble those found in other heat-sensitive organs.
Feeding
It feeds primarily on rodents, especially murid species. However, they will eat just about anything, including rats, mice, shrews, squirrels, land crabs, scorpions and other arthropods. Juveniles are crepuscular, feeding on lizards and foraging actively. As they grow and become adults, they begin to specialize in rodents. Indeed, the presence of rodents is the main reason they are attracted to human habitation. Juveniles are known to be cannibalistic
Reproduction
This species is ovoviviparous. Mating generally occurs early in the year, although gravid females may be found at any time. The gestation period is more than six months. Young are produced from May to November, but mostly in June and July. It is a prolific breeder. Litters of 20–40 are common, although there may be fewer offspring and as little as one. The reported maximum is 65 in a single litter. At birth, juveniles are 215–260 mm in length. The minimum length for a gravid female is about 100 cm. It seems that sexual maturity is achieved in 2–3 years. In one case, it took a specimen nearly 4.5 hours to produce 11 young.
Captivity
These snakes do extremely well in captivity, requiring only a water dish and a hide box. Juveniles feed readily on pinky mice, while the adults will take rats, mice and birds. However, many adults do not feed, with one having refused all food for five months. Breeding is not a problem either. On the other hand, they do make quite dangerous captives. When handled, specimens have been known to use their long, curved fangs to bite right through their lower jaw and into the thumb of the person holding them.
Venom
The amount of venom produced by individual specimens is considerable. Reported venom yields for adult specimens range from 130–250 mg to 150–250 mg to 21–268 mg. For 13 juveniles with an average length of 79 cm, the average venom yield was 8–79 mg (mean 45 mg).
The LD50 in mice, which is used as a general indicator of snake venom toxicity, is as follows: 0.08–0.31 μg/g intravenous, 0.40 μg/kg intraperitoneal, 4.75 mg/kg subcutaneous. For most humans a lethal dose is 40–70 mg. In general, the toxicity depends on a combination of five different venom fractions, each of which is less toxic when tested separately. Venom toxicity also varies within populations and over time.
Envenomation symptoms begin with pain at the site of the bite, immediately followed by swelling of the affected extremity. Bleeding is a common symptom, especially from the gums, and sputum may show signs of blood within 20 minutes post-bite. There is a drop in blood pressure and the heart rate falls. Blistering occurs at the site of the bite, developing along the affected limb in severe cases. Necrosis is usually superficial and limited to the muscles near the bite, but may be severe in extreme cases. Vomiting and facial swelling occurs in about one-third of all cases.
Severe pain may last for 2–4 weeks. Locally, it may persist depending on the level of tissue damage. Often, local swelling peaks within 48–72 hours, involving both the affected limb and the trunk. If swelling up to the trunk occurs within 1–2 hours, massive envenomation is likely. Discoloration may occur throughout the swollen area as red blood cells and plasma leak into muscle tissue. Death from septicaemia, respiratory or cardiac failure may occur 1 to 14 days post-bite or even later.
Because this venom is so effective at inducing thrombosis, it has been incorporated into an in vitro diagnostic test for blood clotting that is widely used in hospital laboratories. This test is often referred to as Dilute Russell's viper venom time (dRVVT). The coagulant in the venom directly activates factor X, which turns prothrombin into thrombin in the presence of factor V and phospholipid. The venom is diluted to give a clotting time of 23 to 27 seconds and the phospholipid is reduced to make the test extremely sensitive to phospholipid. The dRVVT test is more sensitive than the aPTT test for the detection of lupus anticoagulant (an autoimmune disorder), because it is not influenced by deficiencies in clotting factors VIII, IX or XI.
In India, the Haffkine Institute prepares a polyvalent antivenin that is used to treat bites from this species.
Taxonomy
Using morphological and mitochondrial DNA data, Thorpe et al. (2007) provided evidence that the eastern subspecies should be considered a separate species, Daboia siamensis A number of other subspecies may be encountered in literature,The correct spelling of the species, D. russelii has been, and still is, a matter of debate. Shaw & Nodder (1797), in their account of the species Coluber russelii, named it after Dr. Patrick Russell, but apparently misspelled his name, using only one "L" instead of two. Russell (1727–1805) was the author of An Account of Indian Serpents (1796) and A Continuation of an Account of Indian Serpents (1801). McDiarmid et al. (1999) are among those who favor the original misspelled spelling, citing Article 32c (ii) of the International Code of Zoological Nomenclature. Others, such as Zhao and Adler (1993) favor russellii.
In the future, more species may be added to Daboia. Obst (1983) reviewed the genus and suggested that it be extended to include Macrovipera lebetina, Vipera palaestinae and V. xanthina. Groombridge (1980, 1986) united V. palaestinae and Daboia as a clade based on a number of shared apomorphies, including snout shape and head color pattern. Lenk et al. (2001) found support for this idea based on molecular evidence, suggesting that Daboia not only include V. palaestinae, but also M. mauritanica and M. deserti.
Mimicry
Some herpetologists believe that, because D. russelii is so successful as a species and has such a fearful reputation within its natural environment, another snake has even come to mimic its appearance. Superficially, the rough-scaled sand boa, Gongylophis conicus, has a color pattern that often looks a lot like that of D. russelii, even though it is completely harmless.
3) Taipan - Oxyuranus Scutellatus
The taipans are a genus of large, fast, highly venomous Australasian snakes.
Overview
There are three known species: the coastal taipan (Oxyuranus scutellatus), the inland taipan (Oxyuranus microlepidotus) and a recently discovered third species, the Central Ranges taipan (Oxyuranus temporalis). The coastal taipan has two subspecies: the coastal taipan (Oxyuranus scutellatus scutellatus), found along the north-eastern coast of Queensland and the Papuan taipan (Oxyuranus scutellatus canni), found on the southern coast of Papua New Guinea. Their diet consists primarily of small mammals, especially rats and bandicoots.
One species, the inland taipan (Oxyuranus microlepidotus), which is endemic to Australia, has the most toxic venom of any terrestrial snake species worldwide (though the venom of some marine snakes has a higher LD50). Pseudonaja textilis intervenes between the inland and coastal taipan (Oxyuranus scutellatus) which has the third most toxic venom of any land snake. It is also possible that O. temporalis is even more toxic but the research is still in its infancy compared to other species of this genus. This is only a measure of toxicity (LD50) measured as mg/kg of a mouse subject, since it cannot ethically be tested on humans. Venom yield also must be taken as a factor when determining the snake's deadliness to mice. The venom clots the victim's blood, blocking arteries or veins and using up clotting factors. It is also highly neurotoxic. There are no known survivors of a Taipan bite before an antivenene was developed and, even then, victims often require extended periods of intensive care. The taipan was named by Donald Thomson after the word used by the Wik-Mungkan Aboriginal people of central Cape York Peninsula, Queensland, Australia.
The coastal taipan (Oxyuranus scutellatus) is the third most venomous land snake in the world and arguably the largest venomous snake in Australia. Its venom contains taicatoxin, a highly potent neurotoxin. The danger posed by the coastal taipan was brought to Australian public awareness in 1950, when young herpetologist Kevin Budden was fatally bitten in capturing the first specimen available for antivenom research. The coastal taipan is often considered to be one of the deadliest species in the world.
Description
Taipans can grow 6½ to 12 feet long (2 to 3.6 meters). The coastal taipan is usually pale to dark brown in color, fading to a lateral cream, although juveniles are lighter in color. The Papuan taipan is black or purplish-gray, with a copper-colored stripe on its back. They are often found in sugar fields due to an abundance of rats—their main food source. They feed on these two or three times a week.
In several aspects of morphology, ecology and behavior, the coastal taipan is strongly convergent with an African elapid, Dendroaspis polylepis (the black mamba).
2) King Brown Snake - Pseudechis Australis
Pseudechis australis, the common King Brown or Mulga snake, is a species of venomous snake found in Australia. It is one of the longest venomous snakes in the world and the second longest in Australia. Despite one of its common names, "King Brown", it is part of the Pseudechis (black snake) genus.
Description
Mulga snakes are large venomous snakes growing from 2.5 metres to 3 metres in length. It is exceeded in size by the venomous King Cobra, the African Mambas, the Australian Taipan, and genus Lachesis (Bushmaster). Depending on its areal extent, mulga snakes can be of a light brown colour in the desert to a dark brown-blackish colour in the cooler regions of Queensland, South Australia and New South Wales. Mulga snakes are robust with a wide head and smooth snout.
Range
Mulga snakes occur over much of Australia. They are found in most states of Australia except for Victoria and Tasmania. Its range includes all of the Northern Territory, most parts of Western Australia, Queensland, New South Wales and South Australia. It may also be found in the western parts of the Australian Capital Territory.
Habitat
Mulga snakes inhabit woodlands, hummock grassland, chenopod scrubland and almost bare gibber or sandy deserts sheltering under timber, rubbish piles, burrows and deep soil cracks. They are not found in rainforests.
Diet
The mulga snake primarly preys on lizards, birds, mammals and frogs. It is well adapted to eating other snakes, including all venomous snakes.
Venom
The Mulga snake venom consists of neurotoxin. The LD50 is 2.38 subcutaneous. Its venom is not particularly toxic but it is produced in huge quantities. The average tiger snake produces around 10–20 mg when milked. By comparison, a good sized king brown snake may deliver 150mg in one bite.
Black snake anti-venom is used to treat bites from this species, after a CSL Venom Detection Kit has returned a conclusive result for mulga snake envenomation and there are signs that anti-venom usage is required.
Reproduction
Female mulga snakes produce a clutch of around 8–20 eggs, which may be laid in a disused burrow or beneath a log or rock. There is no maternal care for the eggs once they have been laid. Eggs take about 2–3 months to hatch, after which time the new born snakelets must care for themselves.
Taxonomy
The species was first described by John Edward Gray in 1842, who placed it in the genus Naja (cobras). The species was long regarded as monotypic, but several new taxa have recently been described from within P. australis. Two new species and a new genus have been described within this complex by Raymond Hoser: Pailsus pailsei, from near Mount Isa, Queensland, Australia and Pailsus rossignolii, found in Irian Jaya. Hoser later also resurrected Pailsus weigeli (originally described as Cannia weigeli by Wells and Wellington 1987). These descriptions were initially received with skepticism due to the low level of evidence provided in the original descriptions[6]. Later genetic analyses supported the validity of some of Hoser's species, but his genus Pailsus was shown to be a synonym of Pseudechis, and more work is needed to understand species limits among the smaller species of the group.
1) Inland Taipan Or Fierce Snake - Oxyuranus Microlepidotus
The Inland Taipan (Oxyuranus microlepidotus), also known as the Small Scaled Snake and Fierce Snake, is native to Australia and is the most venomous land snake on Earth. It is a species of taipan belonging to the Elapidae family. Although highly venomous, it is very shy and reclusive, and prefers to escape from trouble, biting only if threatened.
Venom
The inland taipan injects 44 mg of venom, consisting of Taipoxin and protease enzymes with each bite on average, and may inject as much as 110 mg at a time. The median lethal dose (LD50) for mice is 2 μg/kg for pure Taipoxin and 0.03 mg/kg for natural venom mixture. Its venom is two-hundred to four-hundred times as toxic as that of most rattlesnakes, and fifty times as toxic as that of a cobra. Its venom is a neruotoxin that could potentially kill an adult human in forty-five minutes.[citation needed] All reported bite victims have been treated with antivenom, and there have been no documented fatalities.[citation needed] As of late 2003, all positively identified inland taipan bite victims have been herpetologists handling the snakes for study, although there have been many unverified reports of bites likely caused by the species.
Appearance
The Inland Taipan is dark tan, ranging from a rich, dark hue to a brownish olive-green, depending on season. Its back, sides and tail may be different shades of brown and grey, with many scales having a wide blackish edge. These dark-marked scales occur in diagonal rows so that the marks align to form broken chevrons of variable length that are inclined backward and downward. The lowermost lateral scales often have an anterior yellow edge. The dorsal scales are smooth and without keels. The round-snouted head and neck are usually noticeably darker than the body (glossy black in winter, dark brown in summer), the darker colour allowing the snake to heat itself while only exposing a smaller portion of the body at the burrow entrance. The eye is of average size with a blackish brown iris and without a noticeable coloured rim around the pupil. It has twenty-three rows of mid-body scales, between fifty-five and seventy divided subcaudal scales, and one anal scale. The Inland Taipan averages approximately 1.8 metres (5.9 ft) in length, although larger specimens can reach lengths of 2.5 metres (8.2 ft).
Geographical distribution
The inland taipan is native to the arid regions of central Australia. Its range extends from the southeast part of the Northern Territory into west Queensland. The snake can also be found north of Lake Eyre and to the west of the split of the Murray River, Darling River, and Murrumbidgee River.
Behavior
Inland Taipan live in holes and feed on small rodents such as mice and rats.
Diet
The Inland Taipan consumes mostly rodents, small mammals, birds and rats. It kills with a single accurate bite, then retreats while waiting for the prey to die before returning to safely consume its meal.
Reproduction
Inland Taipan produce clutches of between one and two dozen eggs. The eggs hatch two months after. The eggs are usually laid in abandoned animal burrows and deep crevices. Reproduction rate depends in part on their diet. If there is not enough food then the snake will reproduce less.
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