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Old 01-21-2010, 05:49 PM   #1 (permalink)
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Default Killer Spiders Invade Sydney

Killer Funnel-Web Spiders Invade Sydney

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Forget sharks and crocodiles: the real menace at this time of year, at least for suburban Sydneysiders, is a backyard spider whose bite can kill you in the space of two hours.

Insect experts have warned that the city is being invaded by funnel-webs, considered one of the world's most aggressive and poisonous spiders. A reptile park north of Sydney where people can drop off captured specimens, and where they are milked of their venom to make antidote, has received more than 40 males in recent weeks. Males are deadlier than females.

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A lengthy dry period, followed by unseasonable downpours and high humidity over the Christmas break, is blamed for the plague. "We've had a long spell of very warm weather combined with rain," said Mary Rayner, general manager of the Australian Reptile Park. "They are starting to come in thick and fast."

The Blue Mountains, west of Sydney, has also reported unusually large numbers of the feared arachnids this summer. Rex Gilroy, who runs a dangerous spiders hotline in the area, told the Sydney Morning Herald: "I think climate change might have something to do with it. This season there's more moisture and coolness, and the spiders have been able to breed up... [The numbers] are definitely up from the previous year, and I think it's not going to get any better."

Several people, including a 12-year-old boy in the Blue Mountains, have already been bitten this summer, but not fatally.

Unlike most spiders, which scuttle away when disturbed, funnel-webs – which can grow to up to two inches long – may rear up and bare their fangs. They make burrows in moist, dark places, such as garden sheds, outdoor laundries and shrubberies.

Ms Rayner warned parents to keep a careful eye on young children. "People should always shake their shoes, never leave washing on the ground or out overnight, and really be careful around laundries and other dark, damp places," she said. "It's important that [parents are] very vigilant about children's clothing and shoes, and where they play."

Last year, a two-year-old boy had to be flown to hospital after being bitten by a funnel-web which had crawled into his gumboot. He displayed the classic symptoms, including vomiting, convulsions and breathlessness, but recovered after being given the anti-venom.

Thirteen people, including seven children, have died from funnel-web bites over the past 100 years, but none since 1981, when an antidote was developed. Still, the experts warn, it pays to be cautious. One species, the paperbark funnel-web, has a bite so lethal that one victim required 17 ampoules of anti-venom.

The spiders are most active in the breeding season, which is normally in February, but weather conditions such as those seen recently can bring them out earlier. Found mainly in eastern Australia, they are said to be able to leap 18 inches, and their fangs can penetrate soft shoes and fingernails.

Killer funnel-web spiders invade Sydney - Australasia, World - The Independent
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Old 01-21-2010, 05:53 PM   #2 (permalink)
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Default Re: Killer Spiders Invade Sydney

A bit about the Funnel Web spider.

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The Sydney Funnel-web Spider (Atrax robustus) is one of 36 species of funnel-web spiders in Australia. Funnel-web spiders prefer moist cool habitats and are found in the south eastern regions of Australia. They live in silk lined burrows and crevices. Their hideouts can easily be identified by the characteristic trip lines radiating from the entrance of the burrow.

The Sydney Funnel-web Spider is mostly found within a radius of 160km from Sydney. (There have been occasional sightings a bit further away.)

It is large (up to 4.5cm for just the body), black, aggressive, and has powerful fangs.

The males often wander into houses, especially in summer and autumn, on their search for females...

It's the time when most Sydney Funnel-web Spider bites happen.


How dangerous is the Sydney Funnel-web Spider?

The male of the species is the most dangerous of the Australian spiders. (This is unusual. Normally the female spiders are more dangerous).

Australian spiders will often bite without injecting venom. But if you get bitten by a large black spider in the Sydney area you should take the bite seriously.

The symptoms of the venom include pain, mouth numbness, vomiting, abdominal pain, sweating and salivation. Whether you have symptoms or not, apply a pressure immobilisation bandage and seek medical help.

But there is no need to panic. Nobody has died from a Sydney Funnel-web Spider bite since an antivenom was introduced in 1984.

Before the introduction of the antivenom the rate of human deaths following a Funnel-web spider bite was less than one every three years, and these fatalities typically took a day or more. There is enough time to administer the antivenom.

(90% of the people bitten never develop symptoms that would warrant the use of antivenom.)

It is interesting to know that the venom of the Sydney Funnel-web Spider is particularly effective in humans. It doesn't affect other mammals, for example cats or dogs, anywhere near as much...


Australian Spiders, Venomous Redback Spider, Poisonous Funnel Web Spider
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