Wikijunior:Bugs/Funnel-Web Spider

What does it look like?
Funnel Web Spiders are hairy and have long legs. They have 3 claws on each leg. They have 8 eyes, but their vision is poor. The abdomen is a slender oval, sometimes with a pattern.

Barn Funnel Web Spiders are about 3/4 of an inch long. They can be grey or brown. There are colored bands on the legs. The back is spotted.

Grass Funnel Web Spiders are orange-brown. Males are about 5/8 of an inch long. Females are about 3/4 of an inch long. They are orange-brown. The head and mid-section (cephalothorax) is yellowish with dark and light bands. Sometimes there are stripes and bands on the abdomen.

Australian Funnel Webs and Northern Tree Funnel Webs are usually black or brown. They are about 1 to 2 inches long. Males are smaller than females. The hard covering on the back (carapace) is shiny with light hairs.

Funnel Web Tarantula Spiders are medium to small in size. Some are only 1/8 of an inch long. Some grow to about 1/2 of an inch long. They are black or brown in color.

Where does it live?
Funnel Web Spiders occur worldwide. They prefer hot and humid regions of North America, Africa, Asia, and Australia. They live on the ground or in trees. They are found among rocks, under logs, in gardens and inside houses. Funnel Webs choose moist, sheltered places to make their webs. Webs are found in crevices, cracks, and corners. They are flat with a funnel-shaped burrow in the middle.

Giant House Spiders are Funnel Webs that live in North America and Europe. They are common in houses and gardens.

Grass Spider Funnel Webs live in North America. They like grassy areas, shrubbery, and buildings. They hang their funnel webs between two branches or two blades of grass.

Barn Funnel Webs and Hobo Funnel Webs are native to Europe. Some species are found in Australia, Central Asia, and Africa. They also live in tropical areas of Central and South America.

Australian Funnel Webs live in trees, especially in eastern coast forests. They like moist, sheltered places. Their burrows can be as much as one hundred feet high in rotted areas of bark.

What does it eat?
Funnel Web Spiders usually eat insects, lizards, and frogs. Sometimes they eat other spiders. They are active at night (nocturnal). They make a flat web with a small funnel-shaped burrow. The web has long fibers that vibrate when prey lands on it. Funnel Webs hide in the burrow, run out to grab the prey, and take it back inside the burrow to feed.

How does it defend itself?
Funnel Web Spiders camouflage their webs under rocks, moss, or rotting logs. They usually make branching tunnels inside the web where they can hide from danger. They run from light to avoid being seen. They will rear up to defend against predators.

What stages of metamorphosis does it go through?
Funnel Web Spiders go through simple, incomplete metamorphosis. There are only three main growth stages: egg, young spider (spiderling), and adult. Spiderlings often look like small versions of adults. They have a hard protective shell (exoskeleton) that does not stretch as they grow. They have to molt (shed) the exoskeleton several times to become an adult.

In summer, males leave their burrows to search for a mate. Females stay close to their webs. After mating, females lay their eggs and surround them with a protective egg sac. The eggs are kept inside the burrow. They are covered with silk and debris. Spiderlings hatch in the spring.

Female Funnel Web Spiders live about 1 year, until cold weather comes. They live for about 2 years in warm regions. Males die shortly after mating.

Grass Spiders place round egg sacs outside the web on a tree or under bark. Spiderlings hatch in spring, disperse, and build small webs. In summer, they make bigger webs nearby.

What special behavior does it exhibit?
Some Funnel Web females call their young to feed using special movements. If a predator is near, females stamp a leg to signal danger so the spiderlings can hide. Females can tell the difference between vibrations made by their young and vibrations made by prey.

How does this bug affect people?
Some larger Funnel Web Spiders have reportedly bitten humans. Some species are deadly; others are not harmful at all.

The bites of all species of Australian Funnel Web Spiders are dangerous to humans. Male Sydney Funnel Web males have a toxic chemical that can cause death. Females do not have this chemical. Females stay near their webs. Males are more likely to bite humans because they wander around to find a mate.

The bites of Northern Tree-dwelling Funnel Webs are deadly. They live in remote mountain areas so rarely come into contact with people.

Antivenom was discovered in the 1980s. No one has died from Funnel Web bites since then.