Question: I have an unusual spider in my front yard. Can you tell me what it is?
Photographer: John Broomfield, Source: Museum Victoria
Answer: This spider is one of the species that are commonly called Golden Orb-weavers. They are so named because if you look at their webs in the right light, they have a distinct golden colour and so do their egg sacs. These beautiful spiders are native to Australia and belong to the genus Nephila which is represented in Australia by five species.
Given that your spider has been collected in Melbourne, it is most likely to be Nephila edulis. Despite the size of this spider, few bites have been recorded. The Golden Orb-weaver is not considered dangerous. Symptoms include localised mild pain and swelling, nausea and dizziness.
Golden Orb-weaving Spiders are not aggressive and their first response to a threat is usually to run. In fact the museum has been contacted by one enquirer who was so taken by his Golden Orb-weaver that he used to stroke her. You should of course do this at your own risk; a spider is quite likely to misread a friendly pat and bite in response to being touched.
Golden Orb-weaving Spider, Nephila edulisPhotographer: Alan Henderson, Source: Museum Victoria
While the female Nephila edulis is a large and impressive spider measuring up to 23 mm in length, the male of the species is only about 6 mm long. Males can usually be found at the edges of a female’s web. The female has distinctive black brushes on 6 of her 8 legs.
A female Golden Orb-weaving Spider constructs a beautiful golden silk egg sac during early winter which is usually left in the tree that she constructed her web on. Golden Orb-weavers can be locally common, for example in the Darling Downs in Queensland a single dead tree can have as many as 30 individual golden orb weaver webs.
Hi Chris - we checked with our Live Exhibits crew about this, and they've replied as follows:
Orbweaver spiderlings tend to balloon away on their silk threads as soon as they are born, and there are no other creatures that would use the same threads. A number of species of caterpillars (usually moths) also use silken threads, so what you describe is most likely one of these.
We don't know what type of wasps were present but at this time of year they are most likely to be Flower Wasps (Scolia soror) which feed on vines but not spiders. If wasps killed the spider, it would have been eaten or removed to be fed to wasp larvae in a nest. This time of year Golden Orbweavers also tend to die of old age as winter approaches, and the behaviour you described confims this as the most likely possibility.
Hi Steven - we checked with our Live Exhibits experts about this, and they have responded as follows:
Nephila edulis tend to produce only one egg sac per season, which explains why her abdomen inflated and deflated, but not why it did so repeatedly. A single egg sac may hold more than 380 eggs, so there will be plenty of offspring to carry on her legacy. Golden Orbweavers have a highly distensible abdomen which allows them to ingest large quantities of food when available and then digest it over several days. This may explain why she appeared tight and full, and then skinny and sagging, although it would be unusual for a spider to have access to very large meals at such regular intervals.
In hot climates where water is available all year round, the spiders are likely to continue to breed throughout the year but still have a period of peak breeding during summer. It's not surprising then, that you're seeing the spiders increase and decrease in size as they produce batches of eggs.
In either case, those are the only two options. Our best guess is that the eggs have been sheltered from sun through the current summer and it's taken a while for enough heat to accumulate within the egg sac.
Hi Corey, the spiders are not known to dismantle their webs, and can sometimes be seen hanging in a complete web just after death. In northern Victoria earlier this year, at the end of summer when most big females died of old age, dozens could be seen dangling from perfect webs throughout the bush.
Spiders spend a lot of time tending to their web, and following a spider’s death the web deteriorates surprisingly rapidly. This is because holes caused by leaves or twigs or flying insects are quickly repaired by the living spider, and smaller ongoing repairs also mitigate the effects of the elements (particularly wind) on the web. Once the spider is gone, the web starts to fall apart.
A second possible cause is that flying creatures with good eyesight, such as small birds, would avoid flying into a web if a spider as large as a Golden Orbweaver were present, but wouldn’t be able to spot the web as easily without the spider present. In the case where the spider is attacked by a bird, either the spider survives with a damaged or destroyed web, then soon repairs it, or the spider dies and the web disappears along with the spider.
Hi Catherine, We have checked this out with the entomologist and she cannot be sure one way or the other. She has advised that they may be her babies, although because the weather has cooled down considerably, it would be normal for the egg sac to wait until Spring to hatch.
Hi Chris, at this time of year, female Golden Orbweavers produce eggs and then die off as the cold weather approaches. You were right to observe that she decreased in size considerably as she offloaded her batch of eggs (which may have been her first or even second batch). One or two batches will be hidden somewhere in foliage at the edge of what was her web. The eggs will hatch in the next few weeks and the spiderlings will disperse to grow throughout spring and summer.
The males of this species are very small and not often seen, and die off much earlier in the year than the females. Some females are still around, but most have died off and the rest will disappear in the next couple of weeks.
Aaron, thanks for the feedback. The abundance of these is likely to be seasonal and linked to the wet summer we have recently experienced, which may have triggered an abundance of food resources. Unfortunately, if it is weather linked, the abundance can't be readily predicted (no more than the weather can, at least)
Hope that is of some help
Thanks for your email. The second webbing of the leaves is probably also an egg sac, as they sometimes lay more than one.
The spider has most likely died by now, as they tend to die off at the end of autumn. In some areas the spiders may survive into winter if the local conditions are warm enough, but in most areas they die off as soon as it gets cold.
The good news is that the spider has left behind a legacy in her egg sacs, which should hatch in a couple of months. The spiders will grow throughout late winter and spring, and start becoming visible in their webs towards the end of the year.
Hi Teresa, thanks for the great feedback. And no, your Golden Orb Weaver does not have OCD! This is one of the characteristics of the Golden Orb Weaver. Check out images on the internet and you will see that this is not unusual.
Please refer to our response on the 27th of March, as it is all explained there. Hope this helps!
Hi Nicholas, Golden Orbweavers are generally considered harmless and there's not usually any need to remove them. In addition, this time of year they are slowly dying out and will disappear completely when the seriously cold weather hits. This species usually lives in northern Victoria and they are not accustomed to the southern Victorian winters.
If you do need to move the spider, it can be placed in a jar by holding the jar over the spider at the front of the web, and using the jar lid to trap the spider from the back of the web. The silk is very strong and may need to be torn by hand. The spider can then be taken to a suitable location and the jar opened and tipped onto the bark of a large tree. Once settled in, the spider will find a good insect-catching location and spin a new web between two trees.
However, the spider may take some time to find a good location and, given the lateness of the season, may not survive long enough to set up a new home.
Hi Kim, we have asked the Live Exhibits Team and they have advised that although the Golden Orb Weaver is a large spider, they are reluctant to bite! The bite, when it does occur, is usually more of a nip than a bite. If your children are happy to watch the spider, and not touch, they should be fine!
We love receiving comments, but can’t always respond.
Hello Marie, Thank you for deciding to use the discovery Centre for your enquiry regarding when the eggs of the golden orb spider hatch. We cannot provide exact information for every species, but generally it appears that the spider lays its eggs in late summer to autumn. During autumn, when the spiderlings emerge, they disperse by ballooning.
Golden Orb-weaving Spiders live on average for about twelve months.
Hi Tamzin, Golden Orbweavers generally live for one year to 18 months, depending on the environmental conditions. For most of this time they are small and not particularly noticeable - it's only as they mature in mid to late summer that they become more obvious. The eggs will remain dormant throughout winter and hatch in early spring.
Science work awesome
To read the latest tweets from @museumvictoria
Follow Museum Victoria on
My father (along with his parents and siblings) travelled to Australia from Southampton UK on the Fairsea arriving in Australia in October 1957. He recalls the...