Garden spiders, Eriophora transmarina, are common across Australia, and can reach 20–24mm in length. They are famed for their large orb (wheel) shaped webs we see in the home garden. Garden spider abdomens have a variety of patterns of colour and shape but two features common to these spiders are the red colouring in the leg joints and their ability to change colour to suit their surroundings. They build their webs at dusk and usually remove all but a single strand in the morning, when they retreat to surrounding shrubbery where their camouflaged bodies are rarely seen. Garden spiders are acutely aware of insect behaviour and when conditions are not favourable for flying insects, no attempt will be made to build a web. When conditions favour flying insects and a meal can be had, they waste no time, weaving a web in about 45 minutes.
These spiders are considered harmless to humans and bites are extremely rare.
Many of us will remember shrieking in horror after blundering through their webs strung across the path on a summer’s night. Disturbed in this manner though, these spiders will usually drop straight to the ground or scurry away and hide.
The Department of Agriculture and Food, Western Australia (DAFWA) is on the lookout for animal and plant pests, diseases and weeds that could pose a threat to agriculture and the environment.
If you discover something unfamiliar, please send a photo to the Pest and Disease Information Service (PaDIS) by email: firstname.lastname@example.org or phone them on Freecall: 1800 084 881.
Please read the sending specimens for identification web article before sending, or bringing in, samples to the Pest and Disease Information Service, 3 Baron-Hay Court, South Perth, 6151, WA.