Pest Profiles » Spiders

What are spiders all about?

Spiders, unlike insects, have 8 jointed legs and their bodies are divided into two sections. Most spiders have 3 or 4 pairs of eyes, situated on the sides and on top of their heads. Their bodies are covered with tiny hairs and spines, which are associated with their sense of touch and taste; they also pick up small vibrations enabling them to ‘hear’. At the rear, and sometimes on the underside, of spider’s abdomens are their spinnerets, which are used to produce silk. The silk is used to weave webs, egg sacks and to wrap up prey. The design of the web varies depending on the species. Spiders are mostly nocturnal, during the day they are seldom seen unless they are sought or disturbed in their natural environments. They are carnivorous, feeding on living or freshly killed insects; some species may kill small lizards and other animals.

There are many different species of spiders found in Australia. Below are some of the well-known and common species that are found in and around homes.

Funnel Web

   
Length    20 to 50mm    
Appearance   Black with reddish hairs    
Found   Eastern Australia, favours moist, dark situations where it spins a silk lined burrow    
Bite   Very toxic and painful may cause death or illness    
Other   There are 16 known species found in Australia. While the Sydney Funnel Web is Australia’s most deadly spider, there are 4 – 5 species that are known to be dangerous to humans. Since 1980, when the antivenin was developed, there have been no fatalities.    

Redback

   
Length    10 – 18mm    
Appearance    Dark brown to black with red stripe down the back, less noticeable in males    
Found   Australia wide, makes a loose web around windows, under eaves, in roof voids, under chairs and outdoor furniture    
Bite   Females inflict a very painful and toxic bite that may cause death or illness. Males do not bite    
Other   The female is much larger than the male and weight for weight is Australia’s most toxic spider. Since the development of the antivenin in 1956 there have been no recorded deaths.    

White-tailed

   
Length   15 – 20mm.    
Appearance      Grey to black with a dirty white mark on the tip of the abdomen    
Found   Australia wide, found under bark on trees and may enter houses in summer months    
Bite   Bite may cause headaches, nausea, chills, blisters and ulcers    
Other   White-tailed spiders’ usually only bite when provoked and are not normally aggressive to humans. Occasionally the bacteria on the fangs of the spider may cause infection or other specific allergic reactions.
   

Huntsman

   
Length   15 – 50mm    
Appearance     Grey to brown, may blend into environment    
Found   Australia wide, lives under bark and in gardens, often enters the house and can be seen mostly at night    
Bite   Non-toxic may be painful but are rare    
Other   Huntsman’s are generally timid and are harmless to humans. They can be beneficial in and around the home as they feed on insects such as cockroaches.    

St Andrews Cross

Length  10 – 20mm    
Appearance  Brown with yellow stripes on the abdomen    
Found    Warmer coastal areas of Australia, build their large webs around gardens and over waterways and ponds    
Bite    May bite but not toxic, harmless to humans    
Other    Spins a large orb type web with four zigzags of silk that form a cross radiating out from the spiders central position.    

Daddy Longlegs

   
Length   5 – 10mm    
Appearance   Grey with long fine legs    
Found   Australia wide    
Bite   Tiny fangs with non-toxic venom means this spider is harmless to humans    
Other   Perhaps the most common spider throughout Australia, they make tiny unsightly webs around window frame and cornice.
   

Spider Bite First Aid

Where possible try to catch the spider for positive identification.

Funnel Web
Apply a firm bandage over the bite and extend the bandage to the extremity of the limb and high up the limb. Keep movement of that part of the body to a minimum and, if possible, lower than the head and heart. Seek immediate medical assistance. Antivenin is available.

Redback
Do not bandage the bite site, use an icepack to ease the pain and swelling, and keep that part of the body still. Seek immediate medical assistance. Antivenin is available.

White-tailed
Wash the bite with disinfectant (detol) and if painful apply an icepack or anesthetic cream. Keep the bite area still and seek medical assistance.

Other Spider Bites
Apply an icepack to the bite area and avoid excessive movement. If symptoms persist seek medical assistance.