Where funnel-webs live, and what to do after a bite
Two funnel-web species share the country around Sydney. One holds the Central Coast down to the Georges River; the other ranges from the Watagans to Bowral, and west into the upper Blue Mountains.
Lines are drawn from the places each source names; the regulator’s map is the boundary.
The two ranges, drawn as one
The Sydney funnel-web’s main range runs from the Central Coast in the north to the Georges River in the south, and west to Baulkham Hills at the southern end of the distribution.
Beyond that, records exist from the Blue Mountains and Wollongong too.
The Southern Sydney funnel-web, Atrax montanus, has a broader sweep again: its range runs from the Watagans to Bowral in the south, and reaches the upper Blue Mountains in the west.
The two species overlap, and this second species is mainly a spider of the south and west of Sydney.
By eye, they cannot easily be told apart. If threatened, both rear up and display their fangs.
Both are shiny and dark brown to black, with finger-like spinnerets at the end of the abdomen. Males are marked by a large mating spur, projecting from the centre of the second pair of legs.
Source: Australian Museum, Sydney funnel-web; Australian Museum, Southern Sydney funnel-web.
How they live, and when you meet them
Funnel-webs live in silk-lined burrows, sheltered under logs and rocks, in places where the climate stays cool and humid.
The Southern Sydney species may need more moisture and shade than the Sydney one, turning up in or near rainforest gullies, under rocks and tree logs.
Dry surface conditions work against them: they dehydrate, and are exposed to birds and lizards.
The spiders most people meet are male. Over summer and autumn the males wander away from their burrows looking for females to mate with.
That wandering is how they turn up in backyards and swimming pools, where they can survive many hours, and sometimes inside houses, where they become trapped.
In the burrow, the spider waits at the entrance for prey: beetles, cockroaches, small lizards or millipedes crossing the silken trip-lines around it.
The mouse spider, the trapdoor spider and the black house spider are all often taken for funnel-webs.
Source: Australian Museum, Sydney funnel-web; Australian Museum, Southern Sydney funnel-web.
After a bite: the first aid
The Queensland Government’s first aid for funnel-web spider bites, word for word:
- Check breathing and circulation If patient is not conscious follow the DRABCD of first aid
- Call 000
- Apply pressure immobilisation bandage: Firmly bandage the area of body involved (including the wound) starting above the fingers or toes (but not so tight as to cause tingling or colour changes)
- If a bandage is not available, something similar such as an item of clothing or towel can be used
- Pressure immobilisation is recommended because it reduces the speed at which the venom spreads throughout the body by collapsing small vessels called lymphatic vessels, which are involved in collecting fluid (and the snake/spider venom) from the body’s tissues and returning it to the bloodstream.
- Immobilise the limb using a splint to reduce the muscles from pumping the venom along the limb
- Encourage the person to sit quietly. Reassurance is important to help keep the patient calm
- If possible, mark the bandage at the site of the bite/sting with a pen so that medical professionals can examine the affected area without taking the bandage off
- Re-check circulation in the fingers or toes that have been bandaged to ensure the bandage is not too tight
- If it is possible and safe to do so, it may be useful to capture the animal involved, for identification purposes, in case anti-venom is required.
- However do not put yourself in danger.
- An ambulance should be promptly called, by dialling 000.
- It is important to stay with the individual concerned in case they deteriorate and require CPR (cardiopulmonary resuscitation) while waiting for medical help to arrive.
Note, applying a tourniquet, cutting or sucking the venom from the wound is not recommended.
New South Wales Health, in its own words: “…keep them still, call an ambulance and apply a pressure immobilisation bandage, with a further bandage to the entire limb.” NSW Health, media release, 6 December 2021
A neurotoxin in the venom attacks the human nervous system, and in the very worst cases the result can be death.
No fatalities have been recorded since antivenom came in.
Source: Queensland Government, bites and stings; NSW Health, media release, 6 December 2021; Australian Museum, Sydney funnel-web.
Big black spiders, and the ones that are not
Mouse spider bites are rare, but the symptoms they cause are like a funnel-web bite’s.
White tail spiders sit on the other side of the line: they are not considered dangerous to humans, and current evidence suggests their bites do not cause skin ulcers.
Most bites from spiders leave nothing but local irritation at the spot. Only the funnel-webs and the redbacks cause harm to people; healthdirect counts every other spider in Australia as generally harmless.
A funnel-web can move very quickly, and when threatened it rears up on its back legs, lunges, and bites with its fangs.
For a bite from a funnel-web or another big, black spider, the steps to take are on healthdirect’s spider bites page.
Source: healthdirect, spider bites; Sydney Children’s Hospitals Network, spider bites.
Who may be paid to treat a home
In New South Wales, occupations and businesses involved in the use of pesticides must be licensed by the Environment Protection Authority. One of those licences is the fumigator licence, and its application sits on Service NSW.
Source: Service NSW, fumigator licence.