Head to head
Sydney Funnel-Web Spider vs Redback Spider
If you ask an Australian to name a dangerous spider, they will say the funnel-web or the redback. They are very different animals. The Sydney funnel-web is a big, black, aggressive burrowing spider with fangs that can pierce a fingernail; the redback is a small, shy widow spider that hangs in a tangled web in the shed. Both have killed people, but only one still can.
| Sydney Funnel-Web Spider | Redback Spider | |
|---|---|---|
| Type | A mygalomorph (primitive) spider, related to tarantulas | A true widow spider (Latrodectus) |
| Size | Body 1–5 cm, robust and glossy black | Body about 1 cm (female), rounded |
| Where you meet it | Burrows in gardens and bush; males wander into houses and pools in warm, wet weather | Dry sheltered nooks: sheds, letterboxes, under furniture, garden pots |
| Temperament | Defensive; rears up and strikes repeatedly | Shy; bites only if pressed against skin |
| Fangs | Large, downward-pointing, can pierce a fingernail | Tiny; the bite is often barely felt at first |
| Venom | Fast-acting; a toxin that overloads the nervous system | Alpha-latrotoxin; causes latrodectism |
| Untreated bite | Can be fatal within hours, especially from a male | Severe pain spreading over hours to days; rarely dangerous |
| Antivenom | Available since 1981; no deaths since | Available since 1956; no clearly confirmed deaths since |
| Bites per year | Relatively few; roughly 30–40 serious | About 2,000, most managed with pain relief |
Funnel-web vs Redback Spider: common questions
Which is more dangerous, a funnel-web or a redback?
The funnel-web, by a clear margin, in terms of how quickly a bite can become life-threatening. A Sydney funnel-web bite, particularly from a male, can kill a healthy adult in hours without treatment. A redback bite is painful and can make you quite unwell for days, but it very rarely threatens life. Since antivenoms were introduced, neither spider has caused a confirmed death in Australia.
Where are you likely to run into each one?
Redbacks like dry, sheltered spots close to the ground around buildings, under garden furniture and pot plants, in sheds, letterboxes, and outdoor toilets, so bites often happen when a hand or foot goes somewhere unseen. Funnel-webs live in burrows in gardens and bush, but the males wander in warm, humid weather looking for mates and end up in houses, in shoes left outside, and in swimming pools.
What should you do if bitten?
For a funnel-web bite, treat it as an emergency: apply a pressure immobilisation bandage to the whole limb, keep the person still, and get to hospital immediately. For a redback, do not use a pressure bandage, which makes the pain worse; just clean the bite, use a cold pack and pain relief, and seek medical care, urgently if symptoms are severe or the patient is a child.