A burgundy goliath bird eater (<i>Theraphosa stirmi</i>) photographed at Virginia Zoo in Norfolk
A burgundy goliath bird eater (Theraphosa stirmi) photographed at Virginia Zoo in Norfolk
Photograph by Joel Sartore, National Geographic Photo Ark

Tarantulas

Common Name:
Tarantulas
Scientific Name:
Theraphosidae
Diet:
Carnivore
Average Life Span In The Wild:
Up to 30 years
Size:
4.75 inches long; leg span: up to 11 inches
Weight:
1 to 3 ounces

Tarantulas give some people the creeps because of their large, hairy bodies and legs. But these spiders are harmless to humans (except for a painful bite), and their mild venom is weaker than a typical bee's. Among arachnid enthusiasts, these spiders have become popular pets.

Molting

Tarantulas periodically shed their external skeletons in a process called molting. In the process, they also replace internal organs, such as female genitalia and stomach lining, and even regrow lost appendages.

Habitat

There are hundreds of tarantula species found in most of the world's tropical, subtropical, and arid regions. They vary in color and behavior according to their specific environments. Generally, however, tarantulas are burrowers that live in the ground.

Hunting

Tarantulas are slow and deliberate movers, but accomplished nocturnal predators. Insects are their main prey, but they also target bigger game, including frogs, toads, and mice. The South American bird-eating spider, as it name suggests, is even able to prey upon small birds.

A tarantula doesn't use a web to ensnare prey, though it may spin a trip wire to signal an alert when something approaches its burrow. These spiders grab with their appendages, inject paralyzing venom, and dispatch their unfortunate victims with their fangs. They also secrete digestive enzymes to liquefy their victims' bodies so that they can suck them up through their straw-like mouth openings. After a large meal, the tarantula may not need to eat for a month.

Natural Threats

Tarantulas have few natural enemies, but parasitic pepsis wasps are a formidable exception. Such a wasp will paralyze a tarantula with its sting and lay its eggs on the spider's body. When the eggs hatch, wasp larvae gorge themselves on the still living tarantula.

Reproduction

The tarantula's own mating ritual begins when the male spins a web and deposits sperm on its surface. He copulates by using his pedipalps (short, leglike appendages located near the mouth) and then scuttles away if he can—females sometimes eat their mates.

Females seal both eggs and sperm in a cocoon and guard it for six to nine weeks, when some 500 to 1,000 tarantulas hatch.

This photo was submitted to Your Shot, our photo community on Instagram. Follow us on Instagram at @natgeoyourshot or visit us at natgeo.com/yourshot for the latest submissions and news about the community.
This photo was submitted to Your Shot, our photo community on Instagram. Follow us on Instagram at @natgeoyourshot or visit us at natgeo.com/yourshot for the latest submissions and news about the community.
Photograph by Juan Osorio, National Geographic Your Shot

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