The Sydney funnel web spider, known scientifically as Atrax robustus, is regarded as one of the most medically significant spiders in the world because of its venom. This guide is for anyone living in or visiting Australia, particularly residents of the Sydney and Central Coast regions where it's most commonly found. It covers identification, habitat, how dangerous it actually is, first aid, and the ecological role this spider plays, so you know what you're looking at and what to do if you find one.
A funnel-web spider is a type of mygalomorph spider that builds a silk-lined, tubular burrow and uses strong, downward-pointing fangs to subdue prey. The Sydney funnel-web spider is native to New South Wales and is found from the Central Coast down to the Georges River, extending as far west as Baulkham Hills, broadly within the Sydney basin and parts of the east coast.
Key Takeaways
- The Sydney funnel-web spider is widely considered the world's most medically significant spider. Thirteen deaths have been attributed to it between 1927 and the early 1980s, all from male bites. There have been no fatalities since antivenom was introduced in 1981.
- Only male Sydney funnel-web venom has been confirmed to kill a human. Female venom lacks the toxin responsible, robustoxin, and no female bite has ever been recorded as fatal.
- Funnel-web spiders are mygalomorphs, with fangs designed to strike downward and pin prey rather than pincer it sideways like true spiders do.
- They build funnel-shaped burrows with irregular silk trip-lines radiating from the entrance, used to detect approaching prey or threats.
- As of 2025, what was long treated as a single species has been split into three: the Sydney funnel-web (Atrax robustus), the Southern Sydney funnel-web (Atrax montanus), and the Newcastle funnel-web (Atrax christenseni), which is larger and more venomous.
The Sydney Funnel Web Spider
Scientific name: Atrax robustus
Location: New South Wales, centred on Sydney, ranging from the Central Coast to the Georges River
Appearance:
- Shiny black or dark brown body
- Females: up to around 3.5 to 5 cm in body length
- Males: smaller and more lightly built, around 2.5 cm, but longer-legged
- Large, powerful, downward-striking fangs
- Broad, glossy cephalothorax
- Finger-like spinnerets at the end of the abdomen
Behaviour:
- Aggressive when cornered or threatened
- Rears up on its back legs, raises its front legs, and displays its fangs as a warning
- Males wander at night, mostly during the warmer months, searching for females
Habitat:
- Burrows in soil, under logs, rocks, and leaf litter
- Bushy suburban areas, open forest, and shady gullies, often on south or east-facing slopes
Venom:
- Male venom contains robustoxin, a neurotoxin that severely affects the human nervous system
- Female venom does not contain robustoxin and has not been linked to any confirmed human death
- Effective antivenom has been available since 1981, and there have been no fatalities since
Ecological role:
- An important predator of insects, small lizards, and other spiders
Human interaction:
- Fatalities are now rare to the point of being effectively eliminated, thanks to antivenom and pressure immobilisation first aid
Understanding what the spider looks like and where it lives is the foundation for everything else in this guide, starting with how to actually identify one.
What Does a Sydney Funnel Web Spider Look Like?
The Sydney funnel-web spider is a large, heavy-bodied spider with a shiny black or dark brown carapace, particularly glossy across the thorax and legs. Its size and appearance are a big part of why it has such a fearsome reputation, but a lot of harmless spiders get mistaken for it too, so knowing the specific details matters.
Appearance Details
- Glossy, near-hairless carapace covering the front of the body
- Slightly hairy, dark abdomen
- Strong, spined legs
- Large fangs, roughly 2 cm long, that point downward rather than pincering sideways
- Finger-like spinnerets visible at the rear of the abdomen
Size Comparison
Body length across the species runs from about 1 cm up to 5 cm, with females generally the larger, stockier sex and males more lightly built but longer-legged. For context on just how large they can get: the largest verified male on record, nicknamed Hercules and handed in to the Australian Reptile Park's venom program, measured 7.9 cm from foot to foot. A female nicknamed Megaspider, donated in 2021, had a leg span of around 8 cm.
Mouse Spiders and Black House Spiders: Other Spiders Often Mistaken for Funnel-Webs
A few other spiders get confused for Sydney funnel-webs, and it's worth knowing the difference.
Mouse spiders (genus Missulena) are also burrowing spiders with a glossy carapace and a similarly heavy build. Their venom can also cause serious illness, and funnel-web antivenom is used to treat mouse spider bites as well, since the two are biochemically similar enough for cross-treatment.
Black house spiders (Badumna insignis) are common around Sydney homes and also dark and glossy, but they're a completely different family, build messy funnel-shaped webs on the outside of walls and window frames rather than burrows in the ground, and their bite is not medically dangerous.
If you're trying to identify a spider you've found and it isn't a funnel-web, our guide to 12 Common Spiders in Australia covers the most frequent look-alikes, and we've also written specifically about the Huntsman Spider and White Tail Spiders, two other spiders people frequently worry about.
Can a Sydney Funnel Web Spider Kill You?
Deaths from Sydney funnel-web bites have been recorded, but they are now extremely rare. Thirteen deaths were attributed to this species between 1927 and the early 1980s, and in every identified case, the bite came from a male. There have been no fatalities since antivenom was introduced in 1981.
Severe envenomation is a medical emergency regardless, and prompt treatment is what makes the difference between a frightening bite and a fatal one.
Symptoms of a Sydney Funnel-Web Spider Bite
Rapid heart rate and rising blood pressure, which can progress to pulmonary oedema
Intense pain at the bite site, often with visible fang marks
Local swelling and numbness
Muscle spasms and twitching
Abdominal pain, nausea, and vomiting
Profuse sweating and salivation
Confusion, and in severe cases, coma
In a clinical review of recorded cases, the median time to onset of severe symptoms was around 28 minutes, though it ranged from as little as 8 minutes to nearly three hours. Children are disproportionately affected: in the same review, 42% of severe envenoming cases were in children, and severe reactions in young children can progress faster than in adults.
How Poisonous Is a Sydney Funnel-Web Spider?
Male Sydney funnel-web venom is several times more toxic than female venom, largely due to robustoxin, a neurotoxin that triggers a flood of neurotransmitters and sends the nervous system into overdrive. It's this mechanism that produces the rapid, severe symptoms described above. Female venom lacks robustoxin and, while still capable of causing pain and local illness, has not been linked to a confirmed human death.
Sydney Funnel-Web Spider First Aid
For funnel-web spider bites, apply a pressure bandage and seek immediate medical attention.
Pressure Immobilisation Technique
- Wrap the bite site firmly with a bandage, as you would for a sprain, not so tight that it cuts off circulation.
- Extend the bandage to cover the entire limb, moving upward from the bite, to slow the spread of venom through the lymphatic system.
- Splint the limb to keep it as still as possible.
- Keep the limb at or below heart level.
- Avoid washing the bite site. Venom residue can help identify the species.
When to Seek Medical Help
Call an ambulance immediately for any suspected funnel-web bite. Do not wait to see whether symptoms develop. Current treatment protocol starts with two ampoules of antivenom for confirmed severe envenomation, though the exact amount needed depends on the case. Antivenom has proven effective even against the newly described Newcastle funnel-web.
Symptoms of a Sydney Funnel-Web Spider Bite
Intense Pain: The bite site may be extremely painful, with visible fang marks.
Severe Symptoms: Symptoms can include local swelling, numbness, spasms, nausea, vomiting, confusion, and even coma.
Rapid Progression: Symptoms may escalate quickly, leading to hypertension, tachycardia, and potentially death within minutes to hours.
Treatment: Promptly applying pressure immobilization bandages and seeking medical help is essential to counteract the venom’s effects.
How long can you survive a Sydney Funnel Web Spider?
Upon encountering a bite from a Sydney Funnel-web Spider, immediate medical attention is imperative due to the highly potent venom. Understanding the severity of the spider‘s bite symptoms can help in taking prompt action.
The Sydney Funnel-web Spider is known for its aggressive behavior and powerful venom, making it essential to seek treatment swiftly. The Australian Reptile Park plays a crucial role in producing antivenom for funnel web bites.
Without antivenom, the bite of a Sydney Funnel-web Spider can be fatal, with symptoms progressing rapidly. It is recommended not to underestimate the danger posed by these spiders, as their presence in populated areas increases the likelihood of encounters. Therefore, knowing how long one can survive a Sydney Funnel-web Spider bite underscores the urgency of seeking immediate medical assistance.
How Painful is a Sydney Funnel Web Bite?
With 14 reported deaths between 1927-1980 attributed to Sydney Funnel-web Spider bites, it is regarded as the deadliest spider in the world. The potency of the female Sydney Funnel-web Spider‘s venom underscores the seriousness of its bite.
The funnel-web spider venom attacks the nervous system, causing severe pain, swelling, sweating, and potentially deadly symptoms like hypertension, tachycardia, and vasoconstriction. Immediate medical attention is essential, with the administration of funnel-web spider antivenom being essential to counteract the venom’s effects.
Immobilisation techniques, applying pressure bandages, and keeping the victim calm can help slow the spread of venom. These spiders are commonly found in forests and have even been known to end up in swimming pools, highlighting the importance of vigilance in areas where they inhabit.
Sydney Funnel-Web Spider First Aid
For Sydney funnel-web spider bites, immediate first aid is ESSENTIAL. The primary aid technique involves applying a pressure immobilization bandage.
First, wrap the bite site firmly with a bandage, then extend the bandage to cover the entire limb to slow the spread of venom through the lymphatic system.
Keep the limb still and at or below heart level. Avoid washing the bite site, as venom residue can aid medical personnel in identifying the spider.
Seek emergency medical assistance for antivenom administration.
Sydney Funnel Web Spider Habitat
Sydney funnel-web spiders live in bushy suburban areas, open and closed forest, and shady gullies, often on south or east-facing slopes. They build silk-lined burrows in soil, under logs and rocks, or in leaf litter, and construct irregular silk trip-lines radiating from the entrance to detect prey and threats.
Male funnel-webs are most likely to be encountered after warm, wet weather, when they leave their burrows at night to search for mates and sometimes wander into garages, shoes, or pools seeking cover from the damp ground. This is when most human bites happen, not because the spider is hunting people, but because it's moving through the same spaces people are.
Understanding their habitat also explains their reproductive behaviour, which follows a similar seasonal pattern.
Do Funnel-Web Spiders Live in Houses?
Funnel-web spiders don't typically live inside houses. They prefer natural burrow habitats, but wandering males can end up indoors, particularly in garages, laundries, or shoes left outside, especially during and after wet weather.
Reproduction
Mating happens mainly during the warmer months, when males leave their burrows in search of receptive females. Males have a mating spur on their second pair of legs, used to hold the female's fangs safely away during mating. After mating, the female lays up to around 100 eggs in a silk egg sac, which she guards for a period before the spiderlings hatch and disperse to build their own burrows.
It takes several years for young spiders to reach maturity. Once mature, males typically live only another six to nine months to around a year before dying, while females can live over ten years, with some records suggesting up to 20.
Diet
Sydney funnel-web spiders are effective ambush predators, feeding on insects, small lizards, and other invertebrates that trigger their trip-lines near the burrow entrance.
How to Get Rid of Sydney Funnel Web Spider Holes in House?
If you're finding funnel-web burrows or wandering spiders around your property, work through these steps.
Seal Entry Points
Check for gaps around doors, windows, and foundations, and seal them to reduce the chance of a wandering spider getting inside.
Tidy Suburban Gardens
Clear clutter, leaf litter, and garden debris, which reduces the sheltered, humid hiding spots funnel-webs prefer.
Manage Higher-Risk Areas
Exercise caution around garden sheds, woodpiles, and dense garden beds, where funnel-webs are more likely to be encountered.
Monitor Laundry Areas and Shoes
Keep laundries and any shoes left outside checked and shaken out, particularly after rain, since these are common places for wandering males to shelter.
Recognise the Signs
Learn to spot silk trip-lines and burrow entrances so you know what you're dealing with before you get close.
Seek Professional Advice
For an infestation or repeated sightings around the home, get in touch with The Local Guys for tailored advice, or look into Spider Control if you'd rather have it handled professionally.
What Is the Lifespan of a Sydney Funnel Web Spider?
Lifespan varies significantly by sex. Females can live for over ten years, with some records suggesting up to 20, spending most of that time inside their burrow. Males mature at around four years old and typically die within six to nine months to about a year after reaching maturity, largely because wandering to find a mate exposes them to predators, dehydration, and traffic.
Frequently Asked Questions
Do Sydney Funnel-Web Spiders have natural predators?
Yes, though not many. Birds and small lizards will take them opportunistically, and some vertebrates show partial resistance to their venom. Parasitic wasps are also known to prey on them.
How do Sydney Funnel-Web Spiders defend themselves?
By rearing up, displaying their fangs, and biting readily when threatened. This aggressive defensive display is part of why they're so feared, even though bites are relatively uncommon given how many people live within their range.
Can funnel-web spiders survive underwater?
Yes. They can trap air bubbles around the hairs on their abdomen and survive submerged for extended periods, which is why they're occasionally found in swimming pools.
Why was the Sydney funnel-web split into three species?
In January 2025, researchers from the Australian Museum, Flinders University, and Germany's Leibniz Institute published DNA and anatomical analysis showing that what had been treated as one species was actually three: the classic Sydney funnel-web (Atrax robustus), the Southern Sydney funnel-web (Atrax montanus), and the newly described Newcastle funnel-web (Atrax christenseni). The existing antivenom remains effective against all three.
Final Thoughts
The Sydney funnel-web spider remains a symbol of both fear and fascination, and for good reason: it's one of the few spiders in the world capable of killing a healthy adult human. But the risk today is a fraction of what it was before 1981. Antivenom, pressure immobilisation first aid, and public awareness have brought fatalities to zero since the program began, even as the population around Sydney has grown into the millions. Understanding this spider, rather than just fearing it, is what actually keeps people safe.
The information presented on this webpage provides general knowledge about Australian spiders and potential treatments. It is not meant to serve as medical advice. In the case of a medical emergency, dial 000 promptly and follow the guidance provided.
The Local Guys Pest Control offers pest management services and specialises in comprehensive pest control solutions, including thorough inspections, advice on preventive measures, treatment plans tailored to your needs, and extermination services for various pests. Reach out to The Local Guys Pest Control for more details.
Disclaimer: The information presented on this webpage provides general knowledge about pests and potential treatments. It is not meant to serve as medical advice. In the case of a medical emergency, dial 000 promptly and follow the guidance provided.
