Protect your loved ones from undue harm
Some spiders are considered harmless and, if anything, do some of our job for us by being natures pest controllers; others though, can be a real danger to your family and your pets.
Spiders can be divided into two main groups –
- Crawling or hunting spiders and;
- Webbing spiders;
Crawling or hunting spiders
These spiders do not live on webs but instead make their home under leaf litter or bark, in hollows or purpose built burrows and in general garden areas. Unlike webbing spiders, they hunt down their prey or lie in wait to ambush their prey.
Control of crawling/hunting spiders is often limited to removal or elimination of each individual spider. Unless the species is considered dangerous, the best method of dealing with these spiders is to move them back into their habitat.
Spraying the external of a building to stop crawling spiders from entering a premises are ineffectual. Direct application onto the spider would be the best method of chemical control.
Frequently very large, will bite if provoked but are not deadly to humans. Legs are crablike and covered in fairly prominent spines. Colour is mainly dull shades of brown or grey. Live in crevices of tree bark. Frequent sheds and garages and other infrequently used places. Are able to travel extremely fast, often using a springing jump while running, and walk on walls and even on ceilings. Tend to exhibit a “cling” reflex if picked up, making them difficult to shake off and much more likely to bite. Eat insects – (cockroaches are a favourite) and even small geckos.
White-tailed spiders are hunters rather than spinning a web to capture prey. Their preferred prey is spiders and they are equipped with venom for hunting. The adult size varies 12 to 20 mm in body length – grey to black in colour with a white section on the end of it’s tail. It prefers cool moist locations – commonly found in garden mulch areas. In summer, it often wanders into buildings, particularly bathrooms, to escape the heat. The bite of a white-tail spider may cause nausea and burning pain followed by swelling and itchiness around the site of the bite.
As the name suggests, these spiders build and live in webs and use this to catch their prey. Mature spiders, when moving in search of food, produce a strand of silk which is carried by the wind until it comes into contact with a building or other stationary object. The spider then travels across this strand of silk and proceeds to build a new web.
Most common household spiders spin their webs over lamps, in curtains, railings, around windows and gutters. Under some conditions, spiders are considered beneficial because they feed on insects. However the unsightly webs used to catch the insects usually outweigh the beneficial aspect.
Management of webbing spiders can include physical measures like trying to eliminate or reduce the food supply (insects) in the infested area e.g. turning off external lights at night. Temporary measures can include the physical removal of webs, however this will not eliminate the spider population.
Most effective chemical management involves sprays that target the spider directly. Chemical on the webs is not always effective since most webbing spiders hang on using claw-like structures which do not readily absorb chemical residues. However, it is recommended that webs do not be removed for a couple of weeks after spraying.
Red-back spider – Latrodectus hasselti
Redbacks are considered one of the most dangerous spiders in Australia. The Redback spider has a neurotoxic venom which is toxic to humans with bites causing severe pain. The female Redback has a round body about the size of a large pea (1 cm long), with long, slender legs. The body is a deep black colour (occasionally brownish), often containing an obvious orange to red longitudinal stripe on the upper abdomen. Webs are usually built in dry, sheltered sites, such as among rocks, in logs, shrubs, old tyres, sheds, outhouses, children’s toys or under rubbish or litter.