This one might not be for those who are apprehensive about the ‘creepy crawlies’ of the bush…
Even though they aren’t often the recipients of much attention, certain species of arthropods (the phylum of animals that are invertebrates and have jointed legs and a segmented exoskeleton) are some of the most interesting of the lot.
Not only are they interesting, but for the most part they play very important roles in the wellbeing of ecosystems. Over many years animals have adapted in unique ways in order to survive; one of the more noteworthy species for me is the Golden Orb-web spider, also known as the banded legged nephilia.
Nearly as impressive as the size of the spider itself, is its web.
Webs are constructed with silk, which is produced by silk glands present in all spiders. Interesting to note is that this silk contains antibacterial properties and is also incredibly strong, the breaking strain of which has been suggested to have a greater breaking strength to diameter ratio than steel! For this reason, it is not uncommon to find small birds entangled in the webs of Golden Orb-web spiders. This specific spider is a member of the nephilia genus of arachnids (arthropods with 8 legs and two body divisions), and are well known for creating large, neatly woven webs. It is usually after a few months of rain that we start seeing small insects emerge in larger numbers and in turn, so too the spiders that eat them. After already having 650mm of rain this rainy season (100mm more than our annual average rainfall!) the webs of these spiders that sometimes span across roads have been seen a plenty and nestled up in the webs lie these not-so-little spiders. It is hard to miss these webs due to the beautiful golden hue of the silk strands and the neatly arranged central area of the web.
This species of spider is able to manipulate the concentration of this golden colour in their webs and they control this in order to find the right balance between attracting certain prey species and avoiding their web being detected. It is theorised that this golden colour is likely to attract bees that might be drawn to the visible yellows reflected in the sunlight (similar in colour to the pollen from flowers), and in the shadows it blends more effectively blends into the surrounding vegetation, remaining undetected by other insects passing through.
Upon discovering one of these webs, it is almost always worth getting out and having a closer look at the creator itself. The female, being much larger in size than the male (usually between 5-10 times) usually remains facing head down in the middle of the web, whilst the male sits on the outskirts – mainly in an attempt to avoid being eaten by her! Not only do the females feed on small insects that get caught in the webs, they will also eat the males if presented with the opportunity. This makes mating an interesting affair and the males have to be cautious when attempting to reproduce.
Although very intimidating at first glance, golden orb-web spiders are harmless to humans and aren’t known to be aggressive unless they are provoked.
The colours of the bush are dominated by various tones of green at the moment, but if you look hard enough between shrubs and bushes you might very well spot the golden glow of an individual’s web. Now you know just a little bit more about the creature that created it!