Tarantulas at Pinnacles National Park

Tarantula in rocky habitat along Condor Gulch Trail

Photo by Gavin Emmons

Autumn Encounters with Tarantulas at Pinnacles National Park

An autumn visit to Pinnacles National Park is often rewarded with a sighting of one of our most fascinating creatures: the tarantula. September and October are the prime months to see male tarantulas ambling day and night in search of mates. They investigate every potential burrow, looking for a female ready to lay eggs in her specially prepared nest.

Why Don't You See Tarantulas During the Rest of the Year?

Tarantulas are present year-round but are typically much more secretive. They spend their days in burrows, emerging only at night to hunt. At any time of the year, if you look carefully for small holes lined with silk, you might find a tarantula looking back at you. You’d be surprised how small a hole a tarantula can fit into.

Tarantula X-ing

Tarantulas are often seen crossing roads. Please obey posted speed limits and watch carefully to avoid running over tarantulas and other wildlife.

Tarantulas in the Food Web

• Diet: Tarantulas eat a variety of insects and other invertebrates, and possibly lizards, snakes, and small rodents. They inject digestive juices into their prey, then mash it with their strong jaws and drink the liquid. After a large meal, a tarantula may wait several months before feeding again.
• Predators: In turn, tarantulas are eaten by lizards, snakes, birds, and tarantula hawks.

Tarantula Hawk: Nature’s Predator

If you think the way a tarantula feeds is gruesome, wait until you learn about the tarantula hawk. Nearly the size of a hummingbird, this is our largest member of the spider wasp family. It has a shiny blue-black body and smoky orange wings and is often seen visiting flowers in summer and fall.

• Hunting Behavior: When the female tarantula hawk is ready to lay her eggs, she hunts for a tarantula. She paralyzes it with a sting and, despite the tarantula’s weight, drags it to a hole where she lays her eggs on it and buries it. The eggs hatch into larvae, which devour the paralyzed tarantula alive from the inside out.

Tarantula Defense Mechanisms

• Bites: Tarantulas may inflict a painful bite if provoked, similar to a bee sting. The tarantula hawk's sting is far more painful. However, tarantulas are generally gentle and rarely use their fangs except to catch prey.
• Stinging Hairs: If alarmed, tarantulas raise their front legs and abdomen to appear aggressive. They may also release stinging hairs from their abdomen, which irritate the skin by embedding themselves with hundreds of tiny hooks.

Unique Adaptations

• Tarantula Web: Tarantulas spin silk, but not to catch prey. Instead, they use it to line their burrows, and females use it to prepare nests and cover eggs.
• Walking on Walls: Unlike web-spinning spiders that have three claws (the middle claw used for web-grasping), tarantulas have a dense pad of hairs in place of the middle claw. Each hair splits into hundreds of microscopic branches called "end feet," allowing tarantulas to walk on walls and even ceilings.
• Spider Senses: Tarantulas have eight eyes but likely don't see well. They lack ears but sense vibrations through thousands of fine body hairs. They taste with special "taste hairs" near their feet and around their mouths and likely smell through pits on their feet.

Life Span and Reproduction

• Maturity: Tarantulas reach maturity around 10 years of age. Males die within a year of mating and may be eaten by the female before mating.
• Female Lifespan: Females can live over 20 years, making them one of the longest-lived spiders.

What's in a Name?

"What ho! What ho! This fellow is dancing mad! He hath been bitten by the Tarantula."
— Edgar Allan Poe

The term "tarantula" originally referred to the southern European wolf spider (Lycosa tarentula), named after the town of Taranto, Italy. It was once believed that the bite of this spider caused a condition called tarantism, which led to uncontrollable weeping and dancing. This frenzied dance, known as the Tarentella, evolved into a popular Italian folk dance and inspired classical compositions.

Until recently, the species of tarantulas found at Pinnacles had not been studied in detail. Research soon to be published will provide a scientific name for the species here, currently classified within the genus Aphonopelma.