Dangerous Spiders in Sydney Homes: How to Identify Them and What to Do

Sydney's Most Dangerous Spider Species

Four spiders cause the most concern in Sydney homes: the funnel-web, the redback, the white-tail and the mouse spider. The funnel-web and mouse spider carry the most serious bites, and both are treated with the same antivenom.

Funnel-Web Spider: Identification, Habitat, and Bite Risk

• What it looks like: Shiny, dark brown to black, with a body 2 to 4 cm long. To identify a funnel-web in Sydney, look for a glossy, hairless head and finger-like spinnerets at the end of the abdomen. When threatened, it rears up and shows its fangs.
• Where it hides: Silk-lined burrows in cool, moist soil under rocks, logs and rockeries. Bushy gardens on the North Shore and in the Hills District carry the highest risk. South of the Parramatta River, recent records cluster around Bankstown and Mortdale.
• Bite risk: The venom attacks the nervous system and can cause sweating, drooling, muscle twitching and breathing difficulty within a short time. Wandering males cause most bites, and young children face the highest risk. No one has died from a funnel-web bite since antivenom arrived in 1981.
• If you find one: Do not touch it. Keep kids and pets clear and call a professional.

Redback Spider: Where They Hide and How Dangerous They Are

• What it looks like: The female has a round black body about 1 cm long, an orange to red stripe on her back and a red hourglass underneath. Males are light brown, 3 to 4 mm long, and rarely bite.
• Where it hides: Letterboxes, sheds, outdoor furniture, pot plants and play equipment, in messy, tangled webs with sticky lines to the ground.
• Bite risk: Pain that can become severe, plus local sweating, muscle weakness, nausea and vomiting. More than 250 Australians receive redback antivenom each year. No deaths have occurred since redback antivenom became available in 1956.
• If you find one: Do not reach into the web. One redback often means more nearby.

White-Tail Spider: What the Bite Really Does

• What it looks like: A dark grey to reddish, cigar-shaped spider 12 to 18 mm long, with banded legs and a white spot at the tip of its abdomen.
• Where it hides: White-tails hunt other spiders at night and follow them indoors, into towels, floor clothing and bedding.
• Bite risk: Burning pain, then swelling and itching. A 2003 study of 130 confirmed bites, published in the Medical Journal of Australia, found no "flesh-eating" ulcers. The bite hurts, but it is not considered dangerous.
• If you find one: Remove it with a container and card, and clear black house spider webs, its main food.

Mouse Spider: Often Confused With Funnel-Web

• What it looks like: A stocky, glossy black spider 10 to 35 mm long with a bulbous head and large jaws. Its eyes are spread across the front of its head, while a funnel-web's sit close together. Male eastern mouse spiders have a blue-white patch on the abdomen.
• Where it hides: Burrows in lawns and garden soil. Males wander by day from late summer to early winter, especially after rain.
• Bite risk: Some mouse spiders carry venom potentially as toxic as a funnel-web's, though serious bites are rare. Funnel-web antivenom works against them.
• If you find one: Treat it exactly like a funnel-web.

Identification Guide: Dangerous vs. Harmless Sydney Spiders

Check three things: colour, body shape and where you found it. Large, glossy black spiders on the ground are the highest risk, and small black spiders with a red stripe are redbacks.

Harmless lookalikes include brown trapdoor spiders (browner and hairier than funnel-webs) and black house spiders (lacy webs in window corners).

Where Dangerous Spiders Hide in Sydney Homes

Dangerous spiders hide in dark, undisturbed spots near ground level: garden beds, garages, letterboxes, shoes and firewood. Most bites happen when someone reaches into one of these places without looking.

Garden, Garage, Letterbox

Rockeries and thick mulch keep soil cool and damp, which funnel-webs and mouse spiders need. Redbacks favour dry garages and letterboxes, so check shelves, boxes and roller door tracks.

Shoes, Under Furniture, in Firewood

Wandering male funnel-webs shelter in any dark gap. Shake out shoes left outside or by the back door before putting them on. Check under low furniture, and wear gloves when moving firewood or pots.

What to Do If You Find a Dangerous Spider

Do not touch it, keep children and pets away, and contain the room if it is indoors. Then call a licensed pest controller to remove it.

1. Close the door and place a rolled towel along the gap underneath.
2. Never scoop a spider from a pool by hand. Male funnel-webs can survive for hours underwater.

First Aid for Spider Bites in Sydney

1. First aid depends on the spider. For a funnel-web, mouse spider or any large black spider you cannot identify, apply a pressure immobilisation bandage and call 000. Redback bites need ice, not a bandage.
2. Funnel-web or mouse spider bite: Call 000. Apply a firm elastic bandage over the bite, then wrap the whole limb. Splint it, keep the person still, and leave the bandage on for hospital staff.
3. Redback bite: Apply ice. A pressure bandage worsens redback pain. Call the Poisons Information Centre on 13 11 26, and go to hospital if pain is severe or spreads.
4. White-tail or other bites: Wash, apply ice, and see a GP if it turns hot, red or weepy.

For species details, see the Australian Museum's Sydney funnel-web spider page. This guide is general information only.

Professional Spider Control: When to Call an Expert

Call a professional as soon as a dangerous spider turns up inside or keeps coming back. Professional spider pest control in Sydney reduces both spiders and the insects they feed on. Book a spider treatment for your Sydney home if:

• You found a funnel-web or mouse spider inside your home or garage.
• Redbacks keep returning to the same outdoor areas.
• Your property backs onto bushland on the North Shore or in the Hills District.

Knock Down has delivered residential spider control in Sydney for more than 20 years, across over 10,000 homes. Our licensed technicians use WHO- and Ministry of Health-approved products across Canterbury-Bankstown, Belmore, Lakemba and the North Shore.

Pair it with general pest control, and see our spring pests guide for what else wakes up as Sydney warms.

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