Toxic and Feared: 7 Facts About the Sydney Funnel-Web Spider

Varying in length (from one to five centimetres in body length) and colour (ranging from black to brown), there are at least 40 species of funnel-web spiders in the world. Recognised by the front part of their body being sparsely haired and glossy-looking, not all species are dangerous. Although several have been known for highly toxic, fast-acting venom.

Often, many people assume that a number of Australian spiders – such as trapdoor spiders, mouse spiders and black house spiders – are funnel-webs. Although they all look similar to anyone who doesn’t look too close, none are as venomous as the funnel-web.

Burying themselves in a funnel-shaped web of silk, the entrance usually opens into the shape of a T or Y, allowing its prey to fall in or be curious about it. When they spot their prey – cockroaches, beetles, millipedes, snails, occasionally frogs and lizards – they ‘dart out’ before sinking their fangs in.

With the web ranging anywhere from 20 centimetres to 60 centimetres in depth, they tend to hide in humid and sheltered places – usually between rocks, under houses or in holes in the trees.

Scary thought, but very true. The funnel-web’s fangs are very sharp and strong – and are much bigger than the fangs of a brown snake – with the ability to pierce through a fingernail and shoe leather. Their bites are initially much more painful than other spiders not only due to the size of the fangs (they leave a clear fang bite mark) and the venom but also because they will usually cling onto you, biting regularly, until they are brushed away.

The Sydney funnel-web spider is one of the most venomous (to humans) spiders in Australia, and second most venomous in the world. Unlike many other spiders where the most toxic venom lies within the female, the male holds venom up to six times more toxic. Within the venom lies neurotoxin atracotoxin that attacks the nervous system and affects the body’s organs; this is most notable in primates (both humans and monkeys) who are bitten, alongside guinea pigs and mice.

Despite the toxicity of the venom for humans, it has been found that some animals such as rats, cats and rabbits are usually unaffected when bitten by a female, whilst there are slight effects seen in cats and dogs when bitten by a male funnel-web spider.

From 1927 to 1981, there were 13 recorded deaths due to male funnel-web spiders; after experiencing symptoms ranging from breathing and circulatory problems, tears, drooling, muscle spasms, diarrhoea and vomiting all within 10 to 30 minutes after being bitten. However, evidence has suggested that the effects can wear off after a few hours as they found that only one in six bites is serious. Luckily for us, antivenom was developed in 1981, and since then, there have been no fatalities.

As the name suggests, the Sydney funnel-web spiders are found in Sydney, although they are found within a 160-kilometre range across Sydney and New South Wales. Whilst you will generally find male funnel-web spiders alone, females have been found to live in colonies of up to and over 100 spiders!

If you get bitten by the funnel-web spider, you should seek help immediately. The venom is fast-acting and potentially lethal if not treated in a matter of hours, although anti-venom is now readily available at healthcare clinics. Until you’re able to receive professional help, apply firm pressure over the bite and keep the affected limb as still as possible so as to prevent the venom from spreading via the bloodstream – this is a process known as the pressure immobilisation technique. Depending on the severity of the laceration and the symptoms present, patients may need to spend a few days in hospital recovering from the effects of the venom. If you are unsure of whether or not the bite was caused by a funnel-web spider, take the insect to the hospital for identification if possible.