Added 1 April 2002

A Look At

Venomous Snakes


Few creatures are so maligned, usually unjustly, as the snake. Yet one of the reasons given, that snakes are "poisonous", is at least a partial truth. Some snakes are indeed capable of inflicting poison on a human being, and some are capable of killing a human, at least if medical attention is not prompt and competent.

Somewhere between 10-20% of the world's snake species are venomous. This does not mean that all of these are dangerous: indeed, a few of them cannot envenomate a human simply because their jaws are too small to administer a bite. Others however can inflict symptoms of sickness and discomfort, at least for a few hours, while others can cause damage or even death to the human body.

Snake venoms are highly complex mixtures of proteins that have traditionally been divided into haemotoxic, cytotoxic and neurotoxic types. Haemotoxic venoms attack blood cells; cytotoxins, the body tissues; and neurotoxins, the nerves. In practice all snake venom has both properties, but in varying degrees. Viper venom is normally haemotoxic, while that of the elapids is usually neurotoxic.

In writing this page there were certain groups of people I wanted to address. The first is those people who dislike snakes because they fear them. The second are the opposite to the first, those people who are fascinated by venomous snakes, but sometimes for the wrong reason. The third is holidaymakers, tourists and backpackers who are nervous of potentially dangerous snakes.

To the first group of people it is worth reiterating this: most snakes in this world are not dangerous to man. Indeed they do us a service, particularly in rural areas, by keeping down the rodent population. In particular, people living in Europe and the cooler parts of North America usually have nothing to fear, even from the venomous species, whose venom is normally not strong. Even in the Third World where most snakebite casualties occur, many could be avoided if the victim had been wearing preventative footwear. As it is, many unfortunate people simply tread barefoot on a startled snake, with unfortunate consequences.

The second group of people needed to be reminded, however, that venomous snakes in captivity are no less dangerous, and are usually more so. There is a certain type of person who is attracted to risk, often to themselves, as witnessed by the growth of extreme sports, for example. However, nobody makes a parachute jump without training first, and similarly nobody should keep venomous snakes without having had prior experience of non-venomous snakes (preferably the faster ones) first (a fortnight looking after a friend's cornsnake doesn't really cut it either!). If you want to keep a venomous snake because you think the venom factor would make it cool, then I question your motivation. Fortunately in most countries there are strict laws governing the keeping of venomous snakes, and although I have questioned some legislation or proposed legislation on other herpetological matters, I agree with this: the keeping of venomous species should be regulated. Keeping a dangerous snake in your home has been likened to having a loaded firearm around the house, except that a gun is less likely to go off in your own face. You may accept the danger to yourself, but unfortunately an escaped or angry snake is just as likely to go for the person standing next to you - your friend, your partner, your child.

And in case you are blasé about the effects of snake venom, I can assure you that it is not like a drug-induced slide into unconsciousness and death. Envenomation from a dangerous snake is painful and often agonising, leading to respiratory distress, hallucinations and tissue necrosis. You may not die, but at times you might wish you had! And although most snake venom can now be dealt with, you may suffer permanent internal organ damage (where the venom has destroyed the tissue), loss of extremities such as fingers and thumbs, and ugly scarring. This is apart from the legal and financial morass that you may find yourself in, including (but not limited to) the loss of the snake itself. I believe that some people can keep venomous snakes legitimately and safely, but most (often for very good reasons that do not reflect in any way on their character) cannot.

Snakes in the grass

To the third group of people (such as those wanting to visit Africa or Australia but who are anxious about the prospect of being bitten by something lurking in the undergrowth), I offer the following advice. This is in no way original but is the essence of several accounts I have read from writers in countries where venomous snakes are commonplace. I am especially indebted to the useful little booklet by John Visser, Dangerous Snakes and Snakebite.

If you are a backpacker or tourist, then you can be assured that in the everyday course of your travels you are not likely to see many snakes. Unlike lizards such as geckos, most snakes shun cities, for example, despite lurid tales of snakes being flushed into the public sewers. Should you see one, it is likely to slither away out of sight if it becomes aware of your presence. If it doesn't, then let it be.

NEXT: A Brief Overview of the Venomous Snakes

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