Mortein

Spiders have eight legs and two body regions. There are many species of spiders worldwide with distinctive appearance. They live almost everywhere, including most gardens and inside houses and buildings. Spiders feed entirely upon living insects or animals small enough for them to catch. They usually lie in wait for their prey, and many build webs to trap them. Spiders reproduce by laying eggs contained in an egg sac. These sacs are usually ball-shaped. Some species hide their sacs in the web or tuck them away elsewhere. Egg sacs frequently contain several hundred eggs.

Not all spiders are poisonous or dangerous to handle as most are too small and inoffensive, or lacking in venom capacity, to cause serious harm to humans. They usually will not bite unless provoked; however, when gardening or working in storage areas, spiders may be disturbed and become aggressive.

Two types of spiders in Australia are capable of inflicting serious injury to humans, with some deaths having been recorded. Funnel web spiders and the red-back spider are venomous and dangerous. The white-tailed spider is not a deadly biter, but its venom can cause discoloration and itchiness of the skin where the bite has occurred. Other spiders such as the black house spider and the garden wolf spider have been known to give painful bites, but are not regarded as dangerous.

The Funnel Web spider is black to very dark brown and large in size (15 - 30mm - with males being smaller than females). The front section of the body, to which the legs attach, is black, shiny and smooth. The female is larger, but both males and females are very aggressive when disturbed and both are dangerous to humans.

Funnel web spiders occur in coastal areas and adjacent mountain ranges from Queensland to Tasmania. The most dangerous member of his group is the Sydney Funnel Web Spider, which is considered one of the most venomous spiders in the world.

These spiders are ground dwellers, making burrows beneath stones, logs and stumps, as well as in existing in cracks and crevices in soil and around foundations in a cool, damp site. The burrow usually has a funnel-shaped silk covered entrance (thus the common name for these spiders), although many other spiders also will construct this type of web.

Funnel web spiders sometimes enter houses at night, especially during the rainy season when they may be driven from their burrows. They will shelter in cool, moist areas such as laundries and bathrooms, under piles of clothing, etc. Some species will be found in drainpipes and roof gutters where leaves have accumulated.

The Sydney funnel web spider does not climb, and will only enter homes where there is ground-level access. Tight fitting doors and windows are key to excluding these spiders from homes. When gardening and working in damp, cool areas frequented by these spiders, heavy gloves and shoes should be worn. If bitten, immediate medical attention should be sought. An antivenom is available.

The Red Back Spider is a close relative of the black widow spider. The female is about 12mm long, jet black, with a longitudinal bright red to orange stripe on the top surface of the abdomen. The male is a smaller, brown spider whose bite is harmless to humans. It builds its irregular webs in undisturbed areas such as garden and building rubbish, holes in logs and trees, boxes, and under floor areas. It also constructs webs in outbuildings, under shelves or eaves, and along fences. It is very often found in gas and water meter boxes, and under toilet seats in unsewered areas.

It is not a particularly aggressive spider and usually retreats when disturbed. It is advisable to wear heavy leather gardening gloves when working in areas where this spider can occur. It can inflict a painful bite that can prove fatal. Seek immediate medical attention if bitten. An antivenom is available.

Symptoms of poisoning and treatment

The funnel web spider bite causes pain and redness around the bite area, numbness around the mouth, twitching of the tongue, nausea, vomiting, stomach pains, heavy sweating, salivation, watering eyes, laboured breathing and mental confusion.

The red back spider bite causes redness, swelling and sweating at the site of the bite, and local pain that spreads and increases with time.

1- Seek medical attention if there is intense pain and rapid swelling around the area of the bite.
2- Keep the victim calm and still to reduce spread of the venom through the body.
3- Apply a tight bandage to the bite and then along the limb toward the body as far as possible (this will restrict movement of the venom).
4- Immobilise the bitten area (if possible use a splint) and take the patient to the nearest hospital as soon as possible.
5- Take the spider, if it can be caught, so the hospital can get a positive identification for treatment purposes.