Habitat of Funnel Web Spiders
Funnel web spiders are so called because they weave funnel shaped
webs. They are mostly ground dwellers, favouring habitat with moist sand
and clays. The most characteristic sign of a Funnel-web's burrow is the
irregular silk trip-lines that radiate out from the burrow entrance of
most species. These trip-lines alert the spider to possible prey. The
lines are exposed to drying out, so high humidity is more favourable to
activity outside the burrow than dry conditions.
The length of funnel web spiders varies from 1.5 to 4.5 centimetres and
they are single-colour - dark brown usually, without any patterns at
all.
In the burrows, under rotting logs, crevices, and border holes Funnel-web’s burrow in moist, cool, sheltered habitats - under rocks, in
and under rotting logs, crevices, and border holes in rough-barked
trees. In the garden area, they prefer rockeries and dense shrubberies,
and are rarely found in more open situations like lawns.
Humidity and warmth factor serves as a perfect habitat for the funnel
web spider. While rain and water logging disrupts their survival. The
female funnel web spider lives very isolated, it remains in the burrow
for almost its entire life. Males are the ones that go out to hunt and
find mates particularly in autumn and summer months. The number of bites
is the highest during the mating season when the male funnel web spiders
enter in houses and garages through small gaps in the doors and window
sills. Mating is dangerous for the funnel web spider as the females are
very aggressive - this is why the male funnel web spiders have to hold
them with the spurs on the second legs.
In order to protect its eggs the female funnel web spider will bite
fiercely, hence this is the period during which the chances of getting
bitten are the highest. It takes only three weeks for the eggs to hatch
and two more months for the babies to leave the nest. Females have an
incredibly long lifespan – up to ten years - while the males die within
a year after they reach maturity. The bite of the funnel web spider is
very dangerous and it can cause severe illness or death in children.
In and around Sydney
In Sydney, funnel-web spiders mostly live in the moist upland forest
areas of the Hornsby Plateau to the north and the Woronora Plateau to
the south, where sheltered burrow habitats abound in both bushland and
gardens. The dry, flatter areas of western Sydney and the Cumberland
Plain have fewer funnel-webs but their numbers increase again in the
foothills of the Blue Mountains.
The largest of all funnel-webs is the Northern Tree Funnel-web Spider -
Hadronyche formidabilis, reaching 4 to 5 cm body length. These spiders
live in the wet forests of northern New South Wales and southern
Queensland and have been found over 30 meters above ground. While many
have their retreats in surface-opening branch rot-holes, some spiders
appear to live and feed entirely inside the deadwood pipe of large
forest trees feeding on beetles and other insects inside the rotting
wood habitat.
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