The White Tailed spider is a species of eight-legged crawly common in Australia, which has had a particularly nasty reputation in recent years. Despite not being one of Australia’s most poisonous spiders (that prize goes to Redbacks and Funnel-webs), the White Tail is nearly as notorious – mainly due to the internet.
For years now, there have been stories of White Tail spider bites causing necrosis – or rotting of the flesh. The claim is that a white tail’s fangs are filled with a horrible cocktail of toxins and deadly bacteria, and their bite will have chunks of skin and flesh rotting off. And because that story is so horrific, people can’t help but read it and pass it on.
For this reason, White Tails have been aggressively hunted and squashed in people’s houses. But is their reputation deserved? Do we really need to do be chasing down and killing every White Tail we catch a glimpse of?
Let’s start with a few essentials about the White Tail spider.
The White Tail is one of the more distinctive spiders you’ll find around the house and garden. They usually have a body up to 18mm long and a leg span of around 28mm (they’re generally small enough to fit entirely on a 20c coin). They have a distinctive, elongated, cigar-shaped body – looking a little like the sports-car version of a spider. They also generally have two small white circles at the very rearmost tip of the abdomen – the distinctive feature from which they get their name.
The body is usually dark reddish to grey, while the legs are generally dark-orange to brown in colour. The females are larger than the males. There are actually multiple species of white-tail (two of which are common), but it’s difficult to tell one species from the other without a microscope, and their behaviour and physiology is very similar.
White Tails like dark places and things to hide under. They don’t spin webs like many spiders do (they can make silk, but typically only use it to make egg-sacks to protect their young). Rather, they tend to hide in small, dark spaces during the day and roam around hunting for food at night. While outdoors, they tend to hide in bark, leaf litter, and under rocks.
Indoors, they try to find similar conditions – and regrettably (for the spider as much as for humans), they often hide in folds of fabric, such as clothing left on the floor. If you’ve ever seen a white-tail around your house and you’re in the habit of leaving your shirts on the floor, maybe give them a quick shake before you put them on.
White Tail spiders are native to Australia and can be found almost everywhere – although they don’t like the tropical regions as much. They have also been inadvertently introduced in New Zealand.
The reality of being bitten by a white tail is (thankfully) far less exciting than the myth.
For starters, White Tails are reluctant biters and generally only bite if they’re provoked or threatened (like when someone tries to put on the clothing they were taking shelter in).
Second, if you get bitten by a White Tail spider, you can probably expect something similar to a bee-sting. There’s generally a burning sensation in the bite area, followed by mild swelling and an itchy red mark. In rare cases, you might suffer a few side effects like nausea or headaches. Most symptoms should resolve within 24 hours, but in some cases, you might have a small irritated sore or lesion in the spot for around 5-12 days.
But what about the stories from the internet of flesh-rotting necrotic ulcers? As it turns out, they’re probably bunkum!
In 2003, a scientific study (published in the Medical Journal of Australia) examined 130 patients with confirmed White Tail spider bites, where the spider was caught and confirmed to be a White Tail by experts. They found most patients reported some pain from the bite, and around 44% had a persistent sore for a few days. Around 9% also suffered things like headaches and nausea. The average length of time that symptoms persisted was about 24 hours.
Of the 130 patients, not a single one suffered from necrotic ulcers or similar types of tissue damage.
Digging down a little further, it was found that in almost all cases of necrotic wounds where a White Tail spider was implicated, the connection was pretty sketchy. No instance was found of a White Tail being seen to inflict the bite. In many cases, the spider was found later and assumed to be the culprit (generally for want of a better explanation).
Currently, there’s simply no evidence to suggest that white tail spiders are the sinister, flesh-rotting monsters the internet has claimed them to be. In the majority of cases, their bite is less harmful than a bee sting. In fact, they’re statistically less dangerous than bee-stings – bees claim about 2-3 lives a year in Australia (generally due to allergies). In contrast, White Tail bites have claimed none.
There’s only one type of spider species currently known to consistently cause necrotic wounds through their bite – the Recluse spider. In particular, the Brown Recluse spider. These are not native to Australia, although there are some indications they may now have been introduced.
White Tail bites are sometimes painful but don’t require significant treatment. None of the 130 patients involved in the study mentioned above needed to be hospitalised.
Generally, start by cleaning the wound site to minimise the chance of infection. Then, apply an ice pack (or a bag of frozen peas at a pinch) to reduce the swelling and numb the wound. That’s about as much as you need to do, really – although it might pay to check your shots (including tetanus) are up to date.
It’s worth knowing that most standard first aid courses provide training in identifying and responding to bites and stings – including spider bites. So if spiders are common in your area, or you want to know how to identify and respond to a potential spider bite, spending a few hours doing a professional first aid course is probably one of the best ways you could invest your time.
It seems like a bizarre idea to want to keep spiders in your house. Especially spiders that like hiding in clothes and which the internet has linked (incorrectly) with flesh-rotting ulcers. Why would I ever want such a thing around?
White Tail spiders don’t eat people. Nor do they lay webs to catch flies or other flying insects. What they do eat is other spiders.
In particular, three favourite foods of the White Tail spider are Black House spiders (those horrible stocky black spiders around the size of a 20c coin), Brown House spiders, and the Redback spider. Black House spiders do have a nasty (although not fatal) bite, while the Redback spider is one of the most poisonous spiders in the world. You want the White Tail around because his favourite past-time at night is hunting, killing, and eating those spiders.
In fact, one of the ways experts recommend keeping your house free of White Tails is by getting rid of the other spiders. Because once you’ve done that, your home isn’t all that interesting to them.
They also eat Daddy-long-legs spiders – which aren’t dangerous, but many of us could do without.
White Tail spiders are tiny little spider hunting assassins. They roam your house at night, hunting down the really nasty spiders and making sure no one ever finds the body. Then they find a nice quiet corner to hide for the day, not leaving any webs for you to walk into. As long as you don’t accidentally try and wear their hiding spot, they’re on your side. So even if it means you need to be careful about leaving shirts on the floor – and perhaps give them a quick shake-out if you do – it’s worth thinking about letting White Tails be.