These spiders can have a leg span of up to 30 cm (12 in) and can weigh over 170g (6 oz). They are a deep-burrowing species, found commonly in marshy or swampy areas living in burrows that they have dug or which have been abandoned by other creatures.
Females mature in 3 to 4 years and have an average life span of 15 to 25 years, while males live only 3 to 6 years. Males are sometimes eaten by their mates. Colors range from dark to light brown with faint markings on the legs. Birdeaters have hair on their bodies, abdomens, and legs.
The Goliath birdeater is fairly harmless to humans, as are most species of tarantulas. Their fangs are large enough to break human skin (0.75–1.5 inches or 1.9–3.8 cm) and carry venom with effects comparable to a wasp’s sting. When threatened they rub their abdomen with their hind legs to release hairs that are a severe irritant to the skin and mucus membranes.