Take a look at these bad boys! Australia's Top 20 venoumus Snakes.

Which snake species is the most venomous depends on the measure used. The average or the maximum venom yield from milking could be suggested, but these measures can be criticised as not reflecting the impact of a real bite. The measure generally acknowledged as best reflecting how dangerous a snake's venom is is that of LD50. The lower this number, the less venom is required to cause death. By that measure, the most venomous snake in the world is Australia's inland taipan (Oxyuranus microlepidotus). The table below gives the top 20 Australian species in order, their LD50, and their distribution. - Coutesy of the Australian Venom Research Unit.

 

20. Black Whipsnake

LD50 >14.2


The black whip snake is grey or dark brown to black with each body scale marked with black. The belly is greyish, with the underparts of the tail reddish. When disturbed, the black whip snake expands its body revealing a distinct pattern of black spots and white dashes. It occurs in a range of habitats from open woodlands to dry forests and is active during the day feeding on small animals such as lizards. It grows to an average length of 1 m.

Black whipsnake

     

19. Small Eyed Snake

LD50 2.67 
The Small-eyed Snake is very secretive and unlikely to be encountered in the open during the day. When disturbed it may thrash about aggressively, but it is usually disinclined to bite. Toxicity of the venom seems to vary geographically, and the effect on humans can range from no symptoms to renal failure and possibly death (one recorded fatality). The venom contains a long-acting myotoxin that continues to attack muscle tissue (including heart muscle) for days after envenomation. A bite should always be treated as serious and medical attention sought as soon as possible  Small eyed snake 
     

18. Red-Bellied Black Snake

LD50 2.52

For its size, the Red-Bellied Black Snake is probably the least dangerous elapid snake in Australia. Despite the number of bites received every year, very few human deaths have resulted (most death records date from early times and the snake's identity was often unconfirmed). Many bite victims experience only mild or negligible symptoms, however a number also end up hospitalized. The health risks to children and pets are greater, due to their smaller size. As individual reactions to envenomation can vary, all suspected bites should be treated as serious and medical attention sought as soon as possible. - See more at: http://australianmuseum.net.au/Red-bellied-Black-Snake/#sthash.NWa3qd3C.dpuf
For its size, the Red-Bellied Black Snake is probably the least dangerous elapid snake in Australia. Despite the number of bites received every year, very few human deaths have resulted (most death records date from early times and the snake's identity was often unconfirmed). Many bite victims experience only mild or negligible symptoms, however a number also end up hospitalized. The health risks to children and pets are greater, due to their smaller size. As individual reactions to envenomation can vary, all suspected bites should be treated as serious and medical attention sought as soon as possible.  
Red-bellied black snake 
     

17. Mulga Snake

LD50 2.38

When threatened, the Mulga Snake inflates its body and holds its head and flattened neck in a wide curve parallel to the ground. It will throw its head and neck from side to side, hissing loudly as it does. If pressed further it will lash out wildly in an attempt to bite. Mulga Snakes bite savagely and may hang on and chew as they inject their venom. The venom is highly toxic and can be expressed in enormous quantities  Mulga snake 
     
16. Collett's Snake Collett’s Snake is relatively placid, but will defend itself if provoked. Firstly it inflates and raises its forebody in a low curve while giving out loud short hisses to deter the offender. This display is repeated until the snake tires and backs away; however if pressed further the snake will strike out and attempt to bite. The venom is considered to be highly toxic, and anyone suspected of being bitten by a Collett’s Snake should seek immediate medical assistance.  Colletts snake 
     

15. Blue- Bellied Black Snake.

aka Spotted Black Snake

Usually a shy animal, the Blue-bellied Black Snake will defend itself aggressively if threatened. It will first give a warning display, hissing loudly and holding its flattened forebody in a low S-shape. Further harassment will cause the snake to strike out, although it sometimes does so with a closed mouth. If the snake does bite it often hangs on and chews, ensuring a good dose of venom is injected. The venom is highly toxic and contains coagulants, haemolysins, neurotoxins and cytotoxins. Anyone suspected of receiving a bite from a Blue-bellied Black Snake should seek immediate medical attention.  Blue-bellied black snake 
     

14. Rough Scaled Snake

LD50 1.36

The Rough-scaled Snake is a shy and extremely nervous snake, and will vigorously defend itself if cornered. A defensive snake will raise its forebody in an S-shape, with the head pointing directly at the offender and the mouth slightly agape. It hisses loudly and explosively and, if approached too closely, will strike out and bite repeatedly before trying to escape. The Rough-scaled Snake has relatively large fangs and highly toxic venom with coagulant, neurotoxic, haemolytic and cytotoxic properties. One human fatality has been attributed to this species, and anyone suspected of being bitten should seek urgent medical attention  Rough Scaled Snake
 
     

13. Stephen's Banded Snake

LD50 1.36

Stephens' Banded Snake is grey to black with brown or cream crossbands.  Specimens from Kroombit Tops, Warwick and the Stanthorpe area (south-eastern Queensland) are often plain black.  The lips are marked with dark vertical dashes.  The belly is cream to grey. This species grows to 1.2 metres. This species is potentially dangerous and a ready biter.  Its venom affects blood clotting. If bitten, apply first aid and seek urgent medical attention. 

 
Stephens banded snake 
     

12. Dugite

LD50 0.660

Because of the snake’s size and highly toxic venom the Dugite is considered to be very dangerous to humans. Its prevalence in residential areas and nervous disposition have helped make it responsible for approximately 70% of all snake bites reporting to Perth hospitals, but thanks to prompt and effective intervention, there has been only one recorded fatality.

Although naturally shy, the Dugite is easily agitated when confronted and will raise its forebody upright in a tight S-shape. It hisses loudly before making a fast snappy strike at the offender, usually aiming high. Fortunately the fangs are very small and may not effectively penetrate solid shoes or heavy fabric; however anyone with a suspected bite should seek immediate medical attention.

 
Dugite 
     

11. Australian Copperhead

LD50 0.560

Copperheads tend to be secretive and prefer to avoid encounters with humans. If cornered a copperhead will hiss loudly, flatten its body and thrash or flick about, but usually without biting. Further provocation will cause the snake to lash out and bite. The venom is powerfully neurotoxic, haemolytic and cytotoxic, and a bite from an adult of any of the species may be potentially fatal without medical assistance. - See more at: http://australianmuseum.net.au/Copperhead#sthash.KjBPDdPH.dpuf
Copperheads tend to be secretive and prefer to avoid encounters with humans. If cornered a copperhead will hiss loudly, flatten its body and thrash or flick about, but usually without biting. Further provocation will cause the snake to lash out and bite. The venom is powerfully neurotoxic, haemolytic and cytotoxic, and a bite from an adult of any of the species may be potentially fatal without medical assistance. 
Australian copperhead 
     

10. Speckled Brown Snake

LD50 0.360

The Speckled Brown Snake is fawn to orange-yellow and often has dark flecks.  Some individuals have dark bands across body.  The belly is cream with irregular orange-pink spots. This species is potentially dangerous.  Its venom is poorly-known but probably mainly neurotoxic.  If bitten, apply first aid and seek urgent medical attention.

 
Spotted brown snake 
     

9. Gwardar

LD50 0.473

Western Brown Snakes in general are fast moving, nervous snakes. They will quickly take cover if given the opportunity, however if caught out these snakes will rear up in a typical “S” stance and face the threat, often with a gaping mouth. Although reportedly not as aggressive as the Eastern Brown Snake Pseudonaja textilis, the Western will readily defend itself if provoked, striking quickly before turning to attempt an escape. The snake’s fangs are quite short (only 2-3 mm), however the venom is very potent and has high neurotoxic and haemolytic activity. A bite from any species of brown snake should be treated as life-threatening and medical attention sought without delay  Gwardar 
     

8. Death Adder

LD50 0.400

The Common Death Adder feeds on frogs, lizards and birds and, unlike most Australian venomous snakes that actively search for prey, this snake sits in one place and waits for prey to come to it. Covering itself with leaves makes it inconspicuous and it lies coiled in ambush, twitching its yellowish grub-like tail close to its head as a lure. Death adders have relatively large fangs and toxic venom and, before the introduction of antivenom, about 60% of bites to humans were fatal  Death adder 
     

7. Black Tiger Snake (Chappel Is.)

LD50 0.194

The Chappell Island Tiger Snake is the largest member of the Tiger Snake family. As one of Australia’s deadliest, it has a big strong body, dark stout head, and can reach up to 1.9m long. It’s magnificent olive-green to black body colouring, with lighter bands and underbelly, sets the Chappell Island Tiger Snake apart from other tiger snakes.  Black tiger snake Chappell Island 
     

6. Beaked Sea Snake

LD50 0.164

This snake’s bite contains enough venom to kill 50 people—about twice as many as the most venomous terrestrial snakes, such as the king cobra or death adder. Most of the beaked sea snake’s human victims are bitten when wading or fishing in muddy water, although no reliable records exist of the numbers killed every year. However, its deadly venom does not protect this snake from being caught in shrimp-trawling nets. This hazard affects many sea snakes, but the beaked sea snake is particularly susceptible because it lives in shallow water and eats shrimp.  Beaked sea snake 
     

5. Black Tiger Snake

LD50 0.131

Black Tiger Snakes are usually active during the day, although during hot weather they will become nocturnal. They have to be dark in colour due to the extreme cold that they must tolerate throughout most of the year in Tasmania. Being black allows the Black Tiger Snake to absorb heat more readily—a necessity for any reptile living in such unbearably cold environments. It also means that they are absolutely spectacular to see and even tougher to spot in the scrub. Their sensitive forked tongue helps this snake to detect which underground burrows contain a food source.  Black tiger snake 
     

4. Tiger Snake

LD50 0.118

The snake's large size, often aggressive defence and toxic venom make it extremely dangerous to humans. Although generally shy and preferring escape over conflict, a cornered tiger snake will put on an impressive threat display by holding its forebody in a tense, loose curve with the head slightly raised and pointed at the offender. It will hiss loudly as it inflates and deflates its body, and if provoked further will lash out and bite forcefully. The venom of the tiger snake is strongly neurotoxic and coagulant, and anyone suspected of being bitten should seek medical attention immediately.  Tiger snake 
     

3. Coastal Taipan

LD50 0.099

The Coastal Taipan is often regarded as the most dangerous snake in Australia. They are extremely nervous and alert snakes, and any movement near them is likely to trigger an attack. Like any snake the Taipan prefers to avoid conflict and will quietly slip away if given the chance, however if surprised or cornered it will ferociously defend itself. When threatened, the Coastal Taipan adopts a loose striking stance with its head and forebody raised. It inflates and compresses its body laterally (not dorso-ventrally like many other species) and may also spread the back of its jaws to give the head a broader, lance-shaped appearance. Invariably the snake will strike, often without any warning, inflicting multiple snapping bites with extreme accuracy and efficiency. The muscular lightweight body of the Taipan allows it to hurl itself forwards or sideways and reach high off the ground, and such is the speed of the attack that a person may be bitten several times before realizing the snake is there.

The venom apparatus of the Coastal Taipan is well developed. The fangs are the longest of any Australian elapid snake, being up to 12mm long, and are able to be brought forward slightly when a strike is contemplated (the fangs of elapids are generally short and ‘fixed’ in position). When the Coastal Taipan strikes it injects a large amount of highly toxic venom deep into the flesh, and studies have shown they are capable of injecting the same amount in a second or third bite. The venom affects the nervous system and the blood’s ability to clot, and victims may experience headache, nausea/vomiting, collapse, convulsions (especially in children), paralysis, internal bleeding, myolysis (destruction of muscle tissue) and kidney damage. The onset of serious symptoms is often rapid, so anyone suspected of receiving a bite must seek medical attention immediately, no matter how trivial the bite may appear. Prior to the introduction of specific antivenom by the Commonwealth Serum Laboratories in 1956, a Taipan bite was nearly always fatal.

 
Coastal taipan 
     

2. Eastern Brown Snake

LD50 0.053

Because the Eastern Brown Snake can cope and even thrive in areas of human disturbance, and its natural range happens to include some of the most populated parts of the country, this species is probably encountered more than any other type of snake. Being an alert, nervous species they often react defensively if surprised or cornered, putting on a fierce display and striking with little hesitation. However, if approached over a distance, they will usually choose to flee or else remain stationary, hoping to avoid detection. The approach distance tolerated before the snake flees is temperature dependent - snakes with a body temperature of < 24º C allow significantly closer approach than do snakes with a body temperature > 24º C. When confronted by an intruder, the Eastern Brown displays one of two forms of threat. In the mild threat, the snake raises the head and anterior part of the body slightly off and parallel to the ground, with the neck spread laterally and slightly hooked but the mouth closed. In this posture, the snake faces the threat side on. If issuing a strong threat, the snake raises the anterior part of the body well off the ground in an s-shaped coil and with the mouth slightly open, ready to strike - in this posture, the snake faces the threat more squarely. Strikes delivered from this posture are slower but more accurate that strikes delivered from other postures. The common feature of both displays is the spreading of the neck, and this behaviour precedes most bites. Observations in captivity have shown that for strikes in general, no matter what the posture, there was no correlation between strike speed and ambient temperature (18º-36 C), body mass or sex. Strike speeds ranged 0.25-1.80 m/sec (mean = 1.11 m/sec; n = 48). The lack of correlation between strike speed and temperature is unexpected in an ectotherm, and suggests that hot snakes are no quicker in their strike than a cool snake, contrary to the common perception.

 
Eastern brown snake 
     

1. Inland Taipan

LD50 0.025

Inland Taipans are rarely encountered in the wild by the average person because of their remoteness and brief above-ground appearance during the day. Compared with the related Coastal Taipan (and despite the alternative name ‘Fierce Snake’) this species is actually quite shy and many reptile keepers regard it as a placid snake to handle. However, like any animal, it will defend itself when provoked. Firstly it makes a threat display by raising its forebody in a tight low S-shaped curve with its head facing the offender. Should the offender choose to ignore the warning the Inland Taipan will strike, making a single bite or several quick bites. Symptoms of envenomation include headache, nausea, vomiting, abdominal pain, collapse and paralysis. The venom of the Inland Taipan is extremely potent and is rated as the most toxic of all snake venoms in LD50 tests on mice. As well as being strongly neurotoxic the venom contains a ‘spreading factor’ (hyaluronidase enzyme) that increases the rate of absorption. The venom’s toxicity coupled with its spreading action makes a bite from a Fierce Snake potentially life-threatening, and anyone suspected of receiving a bite should seek immediate medical attention.

To date only a handful of people have ever been bitten by this species, and all have survived due to the quick application of correct first aid and hospital treatment.

 
Inland Taipan 

LD50: mg/kg in saline by subcutaneous injection in mice.