Banning exotic leather in fashion hurts snakes and crocodiles in the long run


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Yellow anaconda (snake) skins pegged to dry by indigenous people in Argentina.
Tomas Waller, Author provided

Daniel Natusch, Macquarie University; Grahame Webb, Charles Darwin University, and Rick Shine, University of Sydney

We are all familiar with the concept of “fake news”: stories that are factually incorrect, but succeed because their message fits well with the recipient’s prior beliefs.

We and our colleagues in conservation science warn that a form of this misinformation – so-called “feelgood conservation” – is threatening approaches for wild animal management that have been developed by decades of research.

The issue came to a head in February when major UK-based retailer Selfridges announced it would no longer sell “exotic” skins – those of reptile species such as crocodiles, lizards and snakes – in order to protect wild populations from over-exploitation.

But this decision is not supported by evidence.




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Guns, snares and bulldozers: new map reveals hotspots for harm to wildlife


Too simplistic

Banning the use of animal skins in the fashion industry sounds straightforward and may seem commendable – wild reptiles will be left in peace, instead of being killed for the luxury leather trade.

But decades of research show that by walking away from the commercial trade in reptile skins, Selfridges may well achieve the opposite to what it intends. Curtailing commercial trade will be a disaster for some wild populations of reptiles.

How can that be true? Surely commercial harvesting is a threat to the tropical reptiles that are collected and killed for their skins?

Actually, no. You have to look past the fate of the individual animal and consider the future of the species. Commercial harvesting gives local people – often very poor people – a direct financial incentive to conserve reptile populations and the habitats upon which they depend.

If lizards, snakes and (especially) crocodiles aren’t worth money to you, why would you want to keep them around, or to protect the forests and swamps that house them?

Women raise Burmese pythons at a small farm on Hainan Island, China.
Daniel Natusch, Author provided



Read more:
What Australia can learn from Victoria’s shocking biodiversity record


Biggest man-eaters in the billabong

The iconic case study that supports this principle involves saltwater crocodiles in tropical Australia – the biggest, meanest man-eaters in the billabong.

Overharvested to the point of near-extinction, the giant reptiles were finally protected in the Northern Territory in 1971. The populations started to recover, but by 1979-80, when attacks on people started to occur again, the public and politicians wanted the crocodiles culled again. It’s difficult to blame them for that. Who wants a hungry croc in the pond where your children would like to swim?

Saltwater crocs are the reason many beaches are not open for swimming in northern Australia.
Shutterstock

But fast-forward to now and that situation has changed completely. Saltwater crocs are back to their original abundance. Their populations bounced back. These massive reptiles are now in every river and creek – even around the city of Darwin, capital of the Northern Territory.

This spectacular conservation success story was achieved not by protecting crocs, but by making crocs a financial asset to local people.

Eggs are collected from the wild every year, landowners get paid for them, and the resulting hatchlings go to crocodile farms where they are raised, then killed to provide luxury leather items, meat and other products. Landowners have a financial interest in conserving crocodiles and their habitats because they profit from it.

Saltwater crocodile eggs collected in the Northern Territory, Australia.
Daniel Natusch, Author provided

The key to the success was buy-in by the community. There are undeniable negatives in having large crocodiles as neighbours – but if those crocs can contribute to the family budget, you may want to keep them around. In Australia, it has worked.

The trade in giant pythons in Indonesia, Australia’s northern neighbour, has been examined in the same way, and the conclusion is the same. The harvest is sustainable because it provides cash to local people, in a society where cash is difficult to come by.




Read more:
Elephants and economics: how to ensure we value wildlife properly


Decisions without evidence

A collector captures a yellow anaconda in Argentina.
Emilio White, Author provided

So the evidence says commercial exploitation can conserve populations, not annihilate them.

Why then do companies make decisions that could imperil wild animals? Probably because they don’t know any better.

Media campaigns by animal-rights activists aim to convince kind-hearted urbanites that the best way to conserve animals is to stop people from harming them. This might work for some animals, but it fails miserably for wild reptiles.

We argue that if we want to keep wild populations of giant snakes and crocodiles around for our grandchildren to see (hopefully, at a safe distance), we need to abandon simplistic “feelgood conservation” and look towards evidence-based scientific management.

We need to move beyond “let’s not harm that beautiful animal” and get serious about looking at the hard evidence. And when it comes to giant reptiles, the answer is clear.

The ban announced by Selfridges is a disastrous move that could imperil some of the world’s most spectacular wild animals and alienate the people living with them.The Conversation

Daniel Natusch, Honorary Research Fellow, Macquarie University; Grahame Webb, Adjunct Professor, Environment & Livelihoods, Charles Darwin University, and Rick Shine, Professor in Evolutionary Biology, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Snake venom can vary in a single species — and it’s not just about adaptation to their prey


Wolfgang Wüster, Bangor University and Giulia Zancolli, Université de Lausanne

Few sights and sounds are as emblematic of the North American southwest as a defensive rattlesnake, reared up, buzzing, and ready to strike. The message is loud and clear, “Back off! If you don’t hurt me, I won’t hurt you.” Any intruders who fail to heed the warning can expect to fall victim to a venomous bite.

But the consequences of that bite are surprisingly unpredictable. Snake venoms are complex cocktails made up of dozens of individual toxins that attack different parts of the target’s body. The composition of these cocktails is highly variable, even within single species. Biologists have come to assume that most of this variation reflects adaptation to what prey the snakes eat in the wild. But our study of the Mohave rattlesnake (Crotalus scutulatus, also known as the Mojave rattlesnake) has uncovered an intriguing exception to this rule.

What’s in those glands? It depends where you are!
W. Wüster

A 20-minute drive can take you from a population of this rattlesnake species with a highly lethal neurotoxic venom, causing paralysis and shock, to one with a haemotoxic venom, causing swelling, bruising, blistering and bleeding. The neurotoxic venom (known as venom A) can be more than ten times as lethal as the haemotoxic venom (venom B), at least to lab mice.

The Mohave rattlesnake is not alone in having different venoms like this – several other rattlesnake species display the same variation. But why do we see these differences? Snake venom evolved to subdue and kill prey. One venom may be better at killing one prey species, while another may be more toxic to different prey. Natural selection should favour different venoms in snakes eating different prey – it’s a classic example of evolution through natural selection.

This idea that snake venom varies due to adaptation to eating different prey has become widely accepted among herpetologists and toxinologists. Some have found correlations between venom and prey. Others have shown prey-specific lethality of venoms, or identified toxins fine-tuned for killing the snakes’ natural prey. The venom of some snakes even changes along with their diet as they grow.

We expected the Mohave rattlesnake to be a prime example of this phenomenon. The extreme differences in venom composition, toxicity and mode of action (whether it is neurotoxic or haemotoxic) seem an obvious target for natural selection for different prey. And yet, when we correlated differences in venom composition with regional diet, we were shocked to find there is no link.

Variable venoms

In the absence of adaptation to local diet, we expected to see a connection between gene flow (transfer of genetic material between populations) and venom composition. Populations with ample gene flow would be expected to have more similar venoms than populations that are genetically less connected. But once again, we drew a blank – there is no link between gene flow and venom. This finding, together with the geographic segregation of the two populations with different venoms, suggests that instead there is strong local selection for venom type.

Mohave rattlesnake feeding on a kangaroo rat, one of its most common prey items.
W. Wüster

The next step in our research was to test for links between venom and the physical environment. Finally, we found some associations. The haemotoxic venom is found in rattlesnakes which live in an area which experiences warmer temperatures and more consistently low rainfall compared to where the rattlesnakes with the neurotoxic venom are found. But even this finding is deeply puzzling.

It has been suggested that, as well as killing prey, venom may also help digestion. Rattlesnakes eat large prey in one piece, and then have to digest it in a race against decay. A venom that starts predigesting the prey from the inside could help, especially in cooler climates where digestion is more difficult.

But the rattlesnakes with haemotoxic venom B, which better aids digestion, are found in warmer places, while snakes from cooler upland deserts invariably produce the non-digestive, neurotoxic venom A. Yet again, none of the conventional explanations make sense.

Clearly, the selective forces behind the extreme venom variation in the Mohave rattlesnake are complex and subtle. A link to diet may yet be found, perhaps through different kinds of venom resistance in key prey species, or prey dynamics affected by local climate. In any case, our results reopen the discussion on the drivers of venom composition, and caution against the simplistic assumption that all venom variation is driven by the species composition of regional diets.

From a human perspective, variation in venom composition is the bane of anyone working on snakebite treatments, or antidote development. It can lead to unexpected symptoms, and antivenoms may not work against some populations of a species they supposedly cover. Anyone living within the range of the Mohave rattlesnake can rest easy though – the available antivenoms cover both main venom types.

Globally, however, our study underlines the unpredictability of venom variation, and shows again that there are no shortcuts to understanding it. Those developing antivenoms need to identify regional venom variants and carry out extensive testing to ensure that their products are effective against all intended venoms.The Conversation

Wolfgang Wüster, Senior Lecturer in Zoology, Bangor University and Giulia Zancolli, Associate Research Scientist, Université de Lausanne

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Like alchemists with killer precision, brown snakes make different venoms across their lifetime


Timothy N. W. Jackson, University of Melbourne

It’s spring in Australia and that means reptiles are starting to move about again. Including snakes.

The venom of the eastern brown snake (Pseudonaja textilis) is, drop for drop, one of the most potent of any venoms tested on laboratory mice.

Venoms work by targeting the bitten animal with deadly chemicals. And our recent research shows toxins in the venom of eastern brown snakes change as the snakes grow from juveniles to adults. It’s the first example of a significant age-related change in venom from an Australian snake.

It’s a beautiful example of evolutionary adaption, in which the chemistry of the snake’s venom appears to change in parallel with its diet.


Read more: Why I love surrounding myself with venomous critters


What is snake venom?

Venoms are typically a mixture of different toxins, each of which attacks the system of a potential prey animal or predator in a different way.

Sometimes toxins work together, each making the other more powerful, and sometimes they work completely independently, engaging in chemical warfare on multiple fronts.

Brown snake venom contains many toxins, but there is one toxin above all others that is responsible for the life-threatening effects of bites to humans. This toxin is a “haemotoxin”, which means it attacks the blood.

The haemotoxin starts clotting the blood at an extremely elevated rate, using up all of the coagulation factors, which clot the blood under normal circumstances. When all these are used up, the victim is at risk of bleeding to death.

In the worst case scenario this toxin, perhaps working with others, gives the system such a shock that people collapse within a short period of time following the bite. In this situation, immediate CPR can be the difference between life and death.

Why venom evolved

Venom is a tool that has evolved in snakes to help them secure a meal: it gives them a chance of overpowering animals that would otherwise be very difficult for them to subdue. Venom and its toxins are therefore “designed” (by evolution) to mess up the normal operations of a prey animal’s body.


Read more: Curious Kids: how do snakes make an sssssss sound?


The best toxins for this purpose may differ according to the specific type of prey animal (e.g. mammal or reptile), or the condition of that prey animal (e.g. whether it is active or inactive) when the snake finds it. As a result, we often find snakes that feed upon different types of animals have different toxins in their venoms.

This starts to get really interesting when you consider brown snakes, because adult brown snakes seem to have quite different diets from baby brown snakes.

Testing a venom hypothesis

Age-related shifts in venom chemistry have already been demonstrated for the venoms of a few species of pit vipers from the Americas, but not for anything even remotely related to Australian brown snakes.

This wasn’t because people hadn’t looked – several species of Australian snake had been investigated, but no evidence of a significant age-related change in venom had been found for any of them. This made sense to me, because none of those snakes dramatically change their diets throughout their lives.

Brown snakes are special – as far as we know the juveniles eat lizards almost exclusively, whereas the adults are generalists that eat a lot of mammals.

Baby snake venom is different

When we compared venom in adult and baby brown snakes, we did indeed find them to be different. Baby brown snake venom seems to entirely lack haemotoxins: instead, it’s almost exclusively composed of neurotoxins – toxins that attack nerve junctions.

What this suggests is that the haemotoxins that are so dangerous to humans (and lab mice) aren’t very effective against the lizards that baby brown snakes eat. We can make this dietary link with a degree of confidence because many other Australian snakes that feed exclusively on lizards have similar venom – no haemotoxins, only neurotoxins.


Read more: Snakebites are rarer than you think, but if you collapse CPR can save your life


We don’t yet know what this means from a clinical perspective. It may be that baby brown snake venom is less dangerous to humans than adult brown snake venom, but the opposite might also be true – brown snake antivenom might be less effective against the venom of the babies.

There has been at least one fatal bite from a very small brown snake in Australia, so they must be treated with respect at any age.

The ConversationAs always, the best policy for snakes is to leave them alone and let them go about their business, and to teach children to do the same – snakes want no more to do with us than we want with them.

Timothy N. W. Jackson, Postdoctoral Research Fellow, Australian Venom Research Unit, University of Melbourne

This article was originally published on The Conversation. Read the original article.

Curious Kids: What happens if a venomous snake bites another snake of the same species?



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Scientists usually use the word “venomous” rather than “poisonous” when they’re talking about snakes.
Flickr/Sirenz Lorraine, CC BY

Jamie Seymour, James Cook University

This is an article from Curious Kids, a series for children. The Conversation is asking kids to send in questions they’d like an expert to answer. All questions are welcome – serious, weird or wacky!


If a lethally poisonous snake bites another lethally poisonous snake of the same species does the bitten snake suffer healthwise or die? – Ella, age 10, Wagga Wagga.


Hi Ella,

That’s a great question.

If a venomous snake is bitten by another venomous snake of the same species, (for example during a fight or mating), then it will not be affected.

However, if a snake is bitten by a venomous snake of another species, it probably will be affected.

This is probably because snakes have evolved to be immune to venom from their own species, because bites from mates or rivals of the same species probably happen fairly often.

But a snake being regularly bitten by another snake from a different species? It’s unlikely that would happen very often, so snakes haven’t really had a chance to develop immunity to venom from other species.


Read more: Guam’s forests are being slowly killed off – by a snake


Scientists often collect venom from snakes to create anti-venoms.
Kalyan Varma/Wikimedia

Snakes can break down venom in the stomach

Many people believe that snakes are immune to their own venom so that they don’t get harmed when eating an animal it has just injected full of venom.

But in fact, they don’t need to be immune. Scientists have found that special digestive chemicals in the stomachs of most vertebrates (animals with backbones) break down snake venom very quickly. So the snake’s stomach can quickly deal with the venom in the animal it just ate before it has a chance to harm the snake.

People that have snakes as pets often see this. If one venomous snake bites a mouse and injects venom into it, for example, you can then feed that same dead mouse to another snake. The second snake won’t die.


Read more: Curious Kids: How do snakes make an ‘sssssss’ sound with their tongue poking out?


The eastern brown snake, which is found in Australia, is one of the most venomous snakes in the world.
Flickr/Justin Otto, CC BY

The difference between venom and poison

By the way, scientists usually use the word “venomous” rather than “poisonous” when they’re talking about snakes. Many people often mix those words up. Poisons need to be ingested or swallowed to be dangerous, while venoms need to be injected via a bite or a sting.

Some snakes can inject their toxins into their prey, which makes them venomous. However, there seem to be a couple of snake species that eat frogs and can store the toxins from the frogs in their body. This makes them poisonous if the snake’s body is eaten. Over time, many other animals will have learned that it is not safe to eat those snakes, so this trick helps keep them safe.


Hello, curious kids! Have you got a question you’d like an expert to answer? Ask an adult to send your question to us. You can:

* Email your question to curiouskids@theconversation.edu.au

* Tell us on Twitter by tagging @ConversationEDU with the hashtag #curiouskids, or

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The ConversationPlease tell us your name, age and which city you live in. You can send an audio recording of your question too, if you want. Send as many questions as you like! We won’t be able to answer every question but we will do our best.

Jamie Seymour, Associate Professor, James Cook University

This article was originally published on The Conversation. Read the original article.

Snakebites are rarer than you think, but if you collapse, CPR can save your life



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Bites from brown snakes like this one were the most common, followed by
tiger snakes, then red-bellied black snakes.
Matt Clancy/SunOfErat/Wikimedia Commons, CC BY-SA

Geoff Isbister, University of Newcastle

Despite the common belief that Australia has some of the most venomous snakes in the world, our new research shows being bitten by a snake is uncommon in Australia and dying from a snakebite is very rare.

And of the few unlucky people to collapse after venom enters their bloodstream, a bystander performing cardiopulmonary resuscitation (CPR) is the most likely thing to save them.

These are just some of the findings from 10 years of data from the Australian Snakebite Project published today in the Medical Journal of Australia.

Although many people go to hospital with a suspected snakebite, many do not turn out to have envenomation (when venom enters the bloodstream) after all.

In more than 90% of cases people are bitten by a non-venomous snake, venom is not injected when the snake bites (known as a “dry bite”) or are not even bitten by a snake (known as a “stick” bite).

Our analysis of about 1,548 cases of suspected snakebites from all around Australia, showed there were on average just under 100 snake envenomations a year, and about two deaths a year.

The most common snakebites were from brown snakes, then tiger snakes and red-bellied black snakes. Brown snakes were responsible for 40% of envenomations. Collapsing, then having a heart attack out of hospital was the most common cause of death (ten out of 23), and most deaths were from brown snakes.

What happens after a snakebite and how can CPR help?

Venom from a snakebite travels via the lymphatic system to the bloodstream. There, it circulates to nerves and muscles where it can cause paralysis and muscle damage. In the blood itself, the venom destroys clotting factors, which makes the blood unable to clot, increasing the risk of bleeding.

In the most severe cases, most commonly in brown snake bites, someone can collapse because they have low blood pressure (we don’t know for certain what causes the low blood pressure). In this situation, insufficient blood is pumped around the body for the brain and other vital organs.

Clearly the accurate diagnosis of snake envenomation and the timely administration of antivenom are essential to treating snakebites in hospital.

But when people collapse, CPR will keep the blood circulating to the vital organs – and is life-saving – however inexpertly a bystander performs it.

If a snakebite victim collapses, CPR is vital to keep the blood circulating to the vital organs.
from www.shutterstock.com

In other words, we found basic first aid before people reached hospital, of which bystander CPR is one, may be more important than any changes in how people are treated in hospital to improve people’s chance of survival. People who survived after collapsing received CPR on average within one minute of being bitten compared with 15 minutes for those who died.

Our study also showed that in most cases, people used other first-aid measures (pressure bandages and immobilising both the limb and the patient). These aim to prevent the venom travelling from the bite site, via the lymphatic system, to the bloodstream.

Antivenom saves lives for those who need it

Our study confirmed the role of antivenom in treating snakebites and the need for it to be administered before irreversible damage is done to the nervous system and paralysis occurs.

However, we found one in four patients given antivenom had an allergic reaction to it and about one in 20 have severe anaphylaxis requiring urgent treatment.

So it is essential only patients with snake envenomation, and not just a suspected snakebite, are treated with antivenom. We found 49 patients (around 6%) were given antivenom unnecessarily, out of the total 755 patients who received it.

What needs to change?

We know the earlier someone receives antivenom the better. Yet our study found that the time from being bitten until receiving antivenom had not improved over the study period.

So we need to find ways to make sure patients get antivenom as early as possible. This requires laboratory tests that can identify patients with snake envenomation in the first couple of hours after the bite.

It is also essential anyone bitten by a snake or suspected to be bitten by a snake seeks immediate medical attention and goes to hospital by ambulance.

But the best thing is to avoid being bitten in the first place:

  • avoid snakes, difficult if you’re a snake handler (up to 11% of cases in our study), and take care if trying to catch or kill a snake (which led to a bite in 14% of cases)
  • wear long pants and sturdy shoes when walking in the bush or rural areas (47% of snakebites were when people didn’t know one was nearby) or when gardening (8% of cases)
  • be alert inside too, with 31% of snakebites near houses and 14% in buildings.

The ConversationOur study confirms Australian snakes don’t really deserve their deadly reputation, unless you’re a mouse. But if you are bitten, or think you have been, hospital is still the best place for you.

Geoff Isbister, Director, Clinical Toxicology Research Group, University of Newcastle

This article was originally published on The Conversation. Read the original article.

A venomous paradox: how deadly are Australia’s snakes?


Ronelle Welton, University of Melbourne and Peter Hobbins, University of Sydney

Australia is renowned worldwide for our venomous and poisonous creatures, from snakes, spiders and ticks on land, to lethal jellyfish, stingrays and stonefish in our waters. Even the shy platypus can inflict excruciating pain if handled without due care.

Yet while injuries and deaths caused by venomous snakes and jellyfish are often sensationalised in the media, and feared by international visitors, a recent review found that very few “deadly” Australian animals actually cause deaths. Between 2000 and 2013, there were two fatalities per year from snake bites across Australia, while the average for bee stings was 2.2 and for jellyfish 0.25, or one death every four years. For spiders – including our notorious redbacks and Sydney funnel-webs – the average was zero.

Snakes nevertheless strike fear into many people who live in or visit Australia. When we have a higher risk of injury or death from burns, horses, bee stings, drownings and car accidents, why don’t we fear these hazards as we do the sight of a snake?

Snakes and statistics through history

James Bray, Venomous and Non-Venomous Reptiles (1897).
State Library of NSW/Peter Hobbins

When settlers arrived in Australia in the late 18th century, they believed that Australian snakes were harmless. By 1805 it was accepted that local serpents might kill humans, but they were hardly feared in the same way as the American rattlesnake or Indian cobra.

Until the 1820s, less than one human death from snake bite was recorded each year; in 1827 visiting surgeon Peter Cunningham remarked that:

…comparatively few deaths [have] taken place from this cause since the foundation of the colony.

Similar observations were made into the 1840s. What the colonists did note, however, was the significant death toll among their “exotic” imported animals, from cats and sheep to highly valuable horses and oxen.

By the 1850s, living experiments in domestic creatures – especially chickens and dogs – were standard fare for travelling antidote sellers. Given the popularity of these public snake bite demonstrations, from the 1860s, doctors and naturalists also took to experimenting with captive animals. It was during this period that official statistics on deaths began to be collated across the Australian colonies.

One sample from 1864–74, for instance, reported an average of four snake bite deaths per year across Victoria, or one death per 175,000 colonists. In contrast, during the same period one in 6,000 Indians died from snake bites each year; little wonder that around the world, Australian snakes were considered trifling.

The 1890s represented a dramatic period of divergence, though. On one hand, statistical studies in 1882–92 suggested that on average, 11 people died annually from snake bite across Australia. Similar data compiled in Victoria led physician James Barrett to declare in 1892 that snakes posed “one of the most insignificant causes of death in our midst”. On the other hand, by 1895 standardised laboratory studies, aimed especially at producing an effective antivenom, saw a global recognition that Australian snake venoms were among the most potent in the world.

In Sydney, physiologist Charles Martin claimed that Australian tiger snake venom was as powerful as that of the cobra. In 1902, his collaborator Frank Tidswell ranked local tiger snake, brown snake and death adder venoms at the top of the global toxicity table.

Over the ensuing century, this paradox has remained: why do so few Australians die from snake bites when our serpents have the world’s most potent venoms? Why aren’t they more deadly?

Deadly fear

Scientific research has delivered ever-expanding knowledge about venoms, what they do, how they work, how they affect us clinically, and their comparative “potency” based on animal studies. In response we have introduced first aid measures, guidelines, effective clinical management and treatment, which in Australia forms one of the world’s best emergency health care systems.

In contrast, countries where snakebites cause far more deaths generally face challenges in accessing affordable essential medicines, prevention and education options.

Snakes form an essential part of their ecosystems. They do not “attack” humans, mostly being shy animals, but are defensive and prefer to escape.

It would seem that venom potency is not a good measure of deadliness, and it may be a combination of our history, behaviour and belief that creates a cultural fear.

Without understating the potential danger posed by venomous snakes, what we offer instead is reassurance. As nearly two centuries of statistics and clinical experience suggest, most snake bites in Australia are survivable, if managed quickly, calmly and effectively. In fact, encounters with humans all too often prove deadly to the snakes themselves – a paradox that is within our power to change.


The authors are presenting on this topic at the upcoming Emerging Issues in Science and Society event at Deakin University’s Downtown campus on 6 July 2017. Sponsored by the Australian Academy of Science and Deakin University’s Science and Society Network.

The ConversationThe event brings together scientists with humanities and social science scholars to discuss common questions from different angles. For more information on the event and to book tickets see the event’s website.

Ronelle Welton, Scientist, University of Melbourne and Peter Hobbins, ARC DECRA Fellow, University of Sydney

This article was originally published on The Conversation. Read the original article.

Hissstory: how the science of snake bite treatments has changed


Peter Hobbins, University of Sydney

Summer is traditionally Australia’s snake bite season, when both snakes and people become more active. The human death toll is now admirably low, but it wasn’t always so.

Although colonial statistics are highly unreliable, in 1882-1892 about 11 people died from snake bites across Australia a year. Since then, the continent’s population has grown from 2.2 million to 24.3 million, yet on average just two people died from snake bites a year in 2001–2013. While improved transport, communications and ambulance services have all contributed, so have the first aid and medical measures used to counteract snake venom.

Complex colonial remedies

A typical case from 1868 suggests the complexity – and desperation – of colonial remedies. When Victorian railway workers killed a brown snake at Elsternwick Station, they threw its body to stationmaster John Brown. Either the serpent was still alive, or Brown brushed its fangs, when he struck it “with an angry gesture”. The usual signs of envenomation (venom injected into the skin) soon appeared: vomiting, physical weakness then creeping paralysis followed by “coma”. Death, seemingly, was inevitable.

The stationmaster was rushed to nearby Balaclava, where surgeon George Arnold tied a ligature (tourniquet) around Brown’s arm before slicing out the bite site, hoping to remove the venom. He then poured ammonia (a hazardous chemical used today in cleaning) onto the wound to neutralise any remaining venom before urging Brown to drink six ounces (175mL) of brandy to stimulate his circulation.

He waved pungent smelling salts under Brown’s nose then applied a paste-like poultice of mustard to his patient’s hands, feet and abdomen to alleviate internal congestion. Further stimulation followed via electric shocks before the staggering, semi-conscious stationmaster was marched up and down to keep him awake – and alive. Brown, nevertheless, kept deteriorating.

Arnold urgently summoned the colony’s only medical professor, George Halford at Melbourne University, who reluctantly agreed to apply his new snake bite remedy. He opened a vein in Brown’s arm and injected ammonia directly into the bloodstream. The stationmaster revived almost immediately, leading another doctor to assert “the injection of Ammonia saved the man’s life” (do not try this at home).

Name your poison

John Brown’s treatment followed a pattern familiar across Australia from 1800 into the 1960s. While many of the 1868 interventions now seem bizarre – or downright dangerous – they made sense in historical context. Until well into the 20th century, snake bite treatments alternated between three fundamental approaches.

In common with today’s understanding, most European settlers, and many Indigenous cultures, considered venom to be an external “poison” that moved through the body. Physical measures such as ligature or suction were thus common to expel venom or limit its circulation.

A second strand of remedies, from mustard poultices to injected ammonia, sought to counteract its ill effects in the body, often by stimulating heart function and blood flow.

The third approach was to directly neutralise venom itself, for instance, pouring ammonia onto the bite.

Until the 1850s, physical measures dominated, while the next 50 years were the heyday of opposing-action treatments. When Halford’s intravenous ammonia fell from favour (as it didn’t seem to work), it was replaced in the 1890s by injections of another notorious poison: strychnine. At first even more popular than ammonia, this highly toxic plant-based poison was blamed for killing more patients than it saved. Yet by far the most popular colonial remedy, both with practitioners and patients, was drinking copious quantities of alcohol, especially brandy.

The slow premiere of antivenoms

The third approach, directly neutralising venom, underlay both Australia’s hugely popular folk “cures” and the novel “antivenene” technology developed in the 1890s. Now they are known as antivenoms and are created by injecting venom into (generally) horses, prompting an immune response, then purifying antibodies from their blood to inject into snake-bitten patients.

But antivenenes suffered a slow gestation in Australia. The first, targeting black snake venom, was developed in 1897; experimental tiger snake antivenene followed in 1902. But antivenenes are tricky to produce, distribute and store. They also proved difficult to administer, sometimes provoking life-threatening anaphylactic reactions (a severe allergic response).

It wasn’t until 1930 that commercial tiger snake antivenene came onto the Australian market.

Other injections targeting a wider range of serpents. “Polyvalent” antivenene, which is effective against multiple venoms, only emerged from the mid-1950s. Meanwhile, patients continued to undergo various first-aid measures, particularly ligatures and Condy’s crystals (potassium permanganate, used to clean wounds) applied to the bite in the hope of inactivating venom.

Two eternal questions

Current snake bite management only stabilised in the 1980s. Two developments were key: rapid tests to identify the injected venom and a new first-aid strategy.

Scientist Struan Sutherland pioneered the “pressure immobilisation technique”. This recommends tightly wrapping a bandage around the bitten region, adding a splint and minimising movement to slow venom spread.

Not washing or cutting the bite site leaves a venom sample to aid identification and so choose the most appropriate antivenom.

But today’s management is still being evaluated because both venoms and treatments still pose clinical challenges, including severe reactions and long-term damage.

And just as in 1868, two eternal questions remain critical: was it truly a deadly serpent, and did it inject enough venom to kill?

The Conversation

Peter Hobbins, ARC DECRA Fellow, University of Sydney

This article was originally published on The Conversation. Read the original article.