While the term “bird-eating spiders” might conjure images of arachnids devouring feathered prey, it primarily refers to a group of very large tarantulas within the Theraphosidae family. Known for their considerable size and hairy appearance, their unique nature prompts curiosity about their habitats and diet.
Global Habitats
These large tarantulas are found across various continents, inhabiting tropical and subtropical climates. South America is a primary region for many of the largest species, including the Goliath Birdeater (Theraphosa blondi). Countries like Brazil, Venezuela, Guyana, French Guiana, and Suriname host these spiders, particularly within Amazonian rainforests and swampy areas.
Beyond South America, large tarantulas are also distributed across Central America, and even into the southwestern United States and Mexico. Additionally, large tarantulas are found in parts of Africa, often called baboon spiders, and throughout much of Asia. Their presence in these diverse warm environments highlights their adaptability.
Microhabitats and Lifestyles
Within their geographical ranges, these spiders exhibit distinct microhabitat preferences and lifestyles. Some species are arboreal, dwelling in trees and constructing silk retreats within hollows, between leaves, or along branches. Others are terrestrial, living on the ground and seeking shelter under rocks, logs, or shed bark. A significant number are fossorial, digging burrows deep within the soil.
Burrowing species, like the Goliath Birdeater, create deep, silk-lined tunnels that provide stable humidity, temperature, and protection from predators and environmental extremes. The silk lining also stabilizes burrow walls and facilitates movement. Arboreal species utilize silk to create tube-like shelters or “hammocks” in trees, serving as resting places, molting sites, and nurseries. These varied adaptations allow them to thrive in diverse environments, from rainforest floors to savannas and semi-arid regions.
Beyond Birds: Their True Diet
Despite their common name, large tarantulas rarely prey on birds as a regular diet. The name “bird-eating spider” likely originated from an 18th-century engraving by Maria Sibylla Merian, depicting a tarantula consuming a hummingbird, leading to a lasting misconception.
These spiders are opportunistic predators, primarily eating a variety of invertebrates. This includes large insects like crickets, grasshoppers, beetles, and cockroaches, and other arthropods such as centipedes and scorpions. Larger species may also consume small vertebrates like lizards, frogs, toads, and rodents. While they can occasionally prey on small birds, this is uncommon.