SPIDERS

Spiders are a reality of life in Australia. Yes! We are home to the world’s most venomous spiders, but of more than 2,400 species that live here, less than 50 are harmful to humans. Most web building spiders are not dangerous. Ground dwellers are more predatory and you’re more likely to encounter them when gardening or landscaping.

Spiders you are wise to beware of in Northern NSW include Redbacks, Funnel Webs, Black or Grey House Spiders and Mouse Spiders. A couple of spiders that are beneficial to your garden or home include the St Andrew’s Cross Spider and Hunstman Spiders.

REDBACK SPIDERS

The Redback Spider is a serious danger to humans. They inflict a painful bite causing around 2000 reported calls each year. The female is the one you need to beware of – she’s the one with the red stripe.

Red Back Spider

Redback Spider.

Red-back spiders do NOT always have a “red” marking. Males are black and can be quite small. The larger, venomous female is black and has the characteristic red stripe on top of her abdomen. It’s her warning sign.
Female adults get to about 10mm; males much smaller at 3-4mm.
Female is highly venomous; males don’t bite.
Yes, but a messy web, down low or tucked in warm, sheltered locations.
Commonly found in and around people’s houses; makes home in dry, dark places like rubbish piles, letter boxes, under disused furniture, door or window frames, under the lip of bin lids or wooden steps and yes, even toilet seats.
As the female rarely leaves her web, humans are not likely to be bitten unless some part of the body (e.g. the hand) is put into the web.
Redbacks have caused human deaths, but not since anti-venoms were made available in 1981. Only a small amount of venom is required to make a person seriously ill as it attacks the nervous system. If you are bitten, you will notice a sharp, pin-prickling sensation commences within five minutes around the site, slowly becoming hot and increasingly painful, often with localised sweating. Reactions can also involve headaches, nausea, vomiting, abdominal pain, fever, hypertension and in severe cases, paralysis. Pain around the bite area can be excruciating, so if bitten or even suspected, seek medical attention as immediately as possible.

FUNNEL WEB SPIDER

These spiders are highly aggressive when disturbed or cornered and able to inflict multiple bites with their large, hardened fangs. The Australian Reptile Park milks the male funnel web spider for its venom to use for antivenene when people suffer a bite. This video clip “How to Catch a Funnel Web Spider” encourages people to collect the funnel web spider, if possible, and gives instructions on how to do that.  It’s worth watching and nowhere near as scary as it sounds.  Given the Australian Museum reports 30 – 40 people are bitten by funnel webs each year, emergency departments don’t want antivenene stocks to get too low.

Funnel Web Spider

Funnel Web Spider.

Large & black with some serious looking fangs. They are shiny black in colour with a dark purplish brown abdomen with a covering of reddish hairs. Unique identification markings include long spinnerets i.e. the two appendages on the end of the abdomen. Also the male has a distinctive spur on both its second front legs.
The male is about 25mm and the female about 30mm in body length.
Both male and female are toxic but the male is deemed the most dangerous spider in Australia.
No. The funnel web is a ground-dweller living in a funnel-shaped burrow with web silks radiating out from the entrance.
Under low growing plants, logs, leaf piles and rock gardens; moist areas such as laundries, outdoor taps and swimming pools are also attractive places.
The mature male comes out of his burrow when it’s hot and humid looking for a mate particularly after heavy rain – this is when most bites occur. At this time he is known to enter homes, lodge in footwear, clothing and swimming pools, where they can survive several days under water.
Bite is extremely painful and demands immediate medical attention. No fatalities since development of anti-venom in 1981.

BLACK & GREY HOUSE SPIDER

The black house spider is often called the ‘window spider’ because they are often found in window frames and crevices.

Black & Grey House Spider

Black & Grey House Spider.

Dark brown to black velvet textured appearance.
Up to 15mm in body length.
Bite is poisonous but not lethal.
Spins a lacy, messy web.
Prefers dry habitat areas and secluded locations; commonly found in window framing, under eaves, gutters, in brickwork, sheds, toilets and among rocks and bark. Electric lights attract their main food source of moths, flies, mosquitoes and other insects.
They like to build their permanent web inside peoples’ houses as the name suggests. Their web has a tubular retreat which spreads out in a series of broad funnels; that’s how they’re sometimes mistaken for a funnel-web spider. The female spider never leaves her web unless forced to, but keeps on repairing it. Old webs can look grey and woolly from constant additions of silk. Males, when ready to mate, go in search of females in their webs. The male plucks the web of the female to attract her attention.
Some people report severe pain around the bite site, heavy sweating, muscular pains, vomiting, headaches and dizziness. Seek immediate first aid and medical attention as soon as possible.

MOUSE SPIDER

The Australian Museum says they’re not actually sure about the origin of the name of the ‘mouse spider’. Could be that someone found a spider in a deep burrow that had possibly been an old beetle or mouse hole; they are alleged to eat mice; or the large females resemble mice?

Mouse Spider

Mouse Spider.

Females are large with dark brown to black bodies; Have a large bulbous head and jaws; eyes are spread across the front of the head, not closely grouped; males of some species have distinctive colour markings but others are black overall.
Varies from 10mm-35mm.
Yes, toxic and painful but bites are rare.
No, it’s a ground dwelling spider.
Build burrows in creeks and rivers; the ‘mouse spider’ name may have been given for the large, supposedly ‘mouse-like’ burrows they build. These silk-lined burrows in depth and provide refuge from predators and a safe place for the egg sac and spiderlings.
With their powerful jaws and venom, they can tackle prey ranging from ants, beetles and spiders to small lizards and frogs.
Often confused with a funnel-web; though they’re not abundant in built up areas, there are bites on record showing similar symptoms to the funnel-web venom.

ST ANDREWS CROSS SPIDER

These are fascinating spiders that weave a large cross in the centre of their web. When feeling threatened, they shake their web, making it vibrate to scare off prey or blur the vision of other insects.

St Andrews Cross Spider

St Andrews Cross Spider.

Abdomen striped yellow and brown, as illustrated.
Males 3mm-4mm; females 10mm-16 mm.
Low risk (non-toxic) to humans.
Spins a large web to snare flying insects, such as flies and mosquitoes. Considered beneficial.
In summer, in gardens around the home.
This spider usually sits, upside down, in the middle of its web forming a cross, as illustrated.
Non-aggressive, capable of a bite but only causes a mild reaction.

HUNTSMAN SPIDER

Huntsman are the spiders you find on the bedroom or bathroom wall that make you jump six feet and screech like a hyena. There are advantages to having them around though: they prey on other insects.

Huntsman Spider

Huntsman Spider.

Hairy, pale yellow buff to beige brown colour with dark patches on its body; the first 2 pairs of legs are longer than the rear two; flat looking with long, slender legs. These large, flat brown spiders look fearsome with their hairy, long legs but they actually prey on the much more dangerous white-tailed spider, as well as cockroaches and other insects.

An adult Huntsman spider may have a body length of up to 20mm. It’s diameter including legs may reach 45mm.
Low risk (non-toxic) to humans.
No, they prefer to hide under tree bark and don’t rely on a web to catch prey.
Prefers to live under the flaking bark of trees, under flat rocks and under eaves or within roof spaces of buildings but are also often found indoors, perched on a wall.
They look scary but are actually nature’s pest controllers; extremely timid; will run away if given the chance; able to move sideways at lightning speed. Diet consists primarily of insects and other invertebrates, and occasionally small skinks and geckos; they also prey on the much more dangerous white-tailed spider, as well as cockroaches and other insects.
Low risk (mildly toxic to humans) and non-aggressive but a large huntsman has extended fangs and can deliver a deep, painful bite. Beware in summer when the female Huntsman is guarding her egg sacs or young.

SOURCES & RESOURCES

Australian Museum

Australian Environmental Pest Managers Association

EDNIEUW

Wikipedia

Queensland Museum Network

NSW POISONS INFORMATION CENTRE – THE CHILDREN’S HOSPITAL, WESTMEAD

Emergency Telephone: 131 126 (24 hours, within Australia only)

Poisons Infomation

NSW Poisons Fact Sheet – Bites & Stings