The common name of the goliath bird-eating spider is somewhat misleading, as this large tarantula does not usually eat birds (4) (6). Instead, its diet consists largely of insects and other invertebrates, including earthworms (3) (4) (6) (10), although it will also catch small vertebrates such as lizards, frogs and small mammals (3) (4) (6) (11).
The goliath bird-eating spider has quite poor eyesight, and instead detects prey mainly by sensing vibrations in the ground. When prey is detected, the spider will pounce on it and inject it with venom using its two-centimetre-long fangs (4). Like other burrow-dwelling tarantulas, the goliath bird-eating spider is mostly active at night, and it tends to hunt within a fairly limited area around its burrow (5).
Despite its formidable appearance, the goliath bird-eating spider is not generally a threat to humans, with its bite reportedly being little worse than a wasp sting (4) (7). This species uses a number of other methods to defend itself against potential predators. For example, it may attempt to scare off an attacker by rubbing together bristles on its first and second pair of legs, producing a hissing sound (4) (5) (12) (13). It also possesses barbed, irritating hairs on its abdomen, which it can flick at an attacker, potentially causing severe irritation to the skin, eyes, nose and mouth. As a further defence strategy, the goliath bird-eating spider may also rear up on its hind legs, showing its large fangs (4) (5).
The goliath bird-eating spider is generally solitary, and individuals only come together to mate (5). Adult female goliath bird-eating spiders lay around 50 to 150 eggs in a large silk sac (4), which is guarded aggressively (6). The female of this species has been known to add irritating hairs from its abdomen to the silk of the egg sac (4), which may help to protect the developing young from parasitic flies (6) (9).
The female goliath bird-eating spider starts to enlarge her burrow in the two weeks before the eggs are laid. Just before egg laying occurs, she seals the burrow with a layer of thick, whitish silk (9). The female guards the egg sac within the burrow until the young spiderlings emerge, around one to two months later (4) (5) (6), and she does not feed during this time (3).
The young goliath bird-eating spiders remain in the female’s burrow until after their first moult, and then disperse (3) (5). This large spider takes around two to three years to reach maturity (3) (4). Female goliath bird-eating spiders can potentially live for up to 20 years, but males usually only live for around 3 to 6 years (4).