Goliath Birdeater

The Goliath birdeater is the largest spider on Earth by mass and body size, native to the lowland rainforests of northern South America, including Guyana, Suriname, French Guiana, Venezuela, and northern Brazil. It has a densely hairy body covered in coarse brown to reddish-brown setae, thick, powerful legs, and can reach a leg span of up to about 30 centimeters, making it one of the most imposing spiders in the world by appearance alone.

Despite its dramatic common name, earned after early naturalists reportedly observed one preying on a hummingbird, the Goliath birdeater's diet consists mostly of ground-dwelling invertebrates such as insects, other arthropods, and occasionally small vertebrates like frogs, small snakes, or rodents encountered near its burrow. It is a burrowing species, digging or occupying tunnels in the forest floor, often near root systems or amid leaf litter that provides moisture and stability to the burrow walls.

Like other tarantulas in its family, the Goliath birdeater relies heavily on urticating (barbed, irritating) hairs covering its abdomen as its primary defense, kicking clouds of these fine hairs toward a perceived threat with its hind legs rather than attacking directly. It can also produce a distinctive hissing or stridulating sound by rubbing bristles on its legs together when threatened.

• Extremely large, heavy-bodied tarantula covered in dense brown to reddish-brown hairs
• Thick, robust legs with a leg span that can reach roughly 30 cm (about 12 inches), among the largest of any spider
• Fangs are proportionally large compared to most spiders
• Defensive behavior includes kicking urticating hairs from the abdomen and producing an audible hissing sound by rubbing leg bristles together
• Lookalikes: other large Theraphosa species (similar size and coloring, distinguished mainly by subtle hair patterns and range)

Native to the lowland tropical rainforests of northern South America, particularly the Guiana Shield region encompassing Guyana, Suriname, French Guiana, and adjacent parts of Venezuela and Brazil. It lives in burrows dug into the moist forest floor, often near streams, tree roots, or under fallen logs, in areas with consistently high humidity.

The Goliath birdeater is a nocturnal, ambush predator that spends daylight hours within its burrow, emerging at night to hunt for insects, other arthropods, and occasionally small vertebrates near the burrow entrance. It relies on vibration sensing rather than a web to detect prey approaching in the leaf litter. When threatened, its primary defenses are kicking clouds of barbed urticating hairs from its abdomen and producing an audible hissing sound by rubbing specialized bristles on its front legs together, both intended to deter would-be predators before any physical contact.

Females produce a large silken egg sac containing several hundred eggs, which they guard within or near the burrow. Spiderlings hatch after several weeks and disperse to establish their own small burrows in the forest floor. Growth is slow, with the spider undergoing numerous molts over several years before reaching adulthood. As with most tarantulas, females live considerably longer than males, with documented lifespans reaching into the double digits in the wild and in captivity, while males have a much shorter adult lifespan after maturing.