Tens of thousands of tarantulas set to crawl across parts of US soon

If you have arachnophobia and plan on hiking or camping in a state in the Southwest or West, be warned –– it’s tarantula mating season. Across California, Colorado, Kansas, New Mexico and Texas, tens of thousands of male tarantulas will soon be emerging from burrows in search of a female mate. 

“If you’re lucky enough you can sometimes see them in hordes crossing the roads at certain times of year,” Dan McCamish, a senior scientist with California State Parks, told USA Today. 

Look but don’t touch

For those not so squeamish, McCamish notes that picking them up still isn’t the wisest idea.

Touching these spiders can be painful due to the tiny barbed hairs on their abdomen, known as urticating hairs. “They can actually flick those hairs off their back feet like darts,” McCamish said. When the hairs get on the skin or in an individual’s eye it can cause irritation.

Picking them up is also bad etiquette. “It’s a wild animal –– it doesn’t want to be picked up and loved and hugged,” McCamish said. “In general, the species is very docile, but if you were to handle one they could bite you.”

If that doesn’t discourage people, maybe this fact will: Tarantulas can jump as high as 2 feet, and they are capable of getting into trees.

“They’re ambush predators, after all,” McCamish said. “Just because they’re ground dwelling creatures that doesn’t mean they don’t climb bushes or trees.”

McCamish also notes that spiders are not a significant danger to humans. The only exception is for individuals who are severely allergic to spider bites. 

Because they’re timid creatures, watching them from a few feet away is safe. “If it starts coming towards you, give it some space,” McCamish said. “It might be defending its eggs, or you might have interrupted a mating ritual between a male and female.”

Where can you find them?

These arachnids live largely in dry climates in the Western and Southwestern United States. They are most common in Arizona, California, Texas, New Mexico, Nevada, Utah, Colorado, Oregon and Washington.

Overall, there are 29 individual species of tarantula in the nation, and they can even be found in Florida, Oklahoma and Missouri.

Some of the most common species are the desert blonde tarantula and the Texas brown. These spiders mostly keep to themselves and nest underground, so people don’t often get to see them. 

Creatures of the night

“As with most things that live in the desert in the summer, they’re generally nocturnal,” said McCamish. “So unless you’re out in the middle of the night, which I don’t recommend for safety purposes, you likely won’t see them.”

Come fall, from September through November, the weather begins to change.

“They generally wait for the first fall seasonal rain –– they really respond to the late summer warmth and the increase in moisture, “ McCamish said, adding, “The males are the ones you’ll see crawling around. If you come upon a tarantula out in the wild and it’s wandering about, it’s likely a male. If you come upon one that’s sitting in its burrow or on top of a hole, it’s likely a female waiting for males to mate with.”

Both sexes stay in their burrows during the winter, where they go into a dormant state that isn’t quite hibernating. When spring hits, they’re back on the hunt, but not too far from their nests. The spiders construct webs near their burrows where they trap smaller insects to eat. 

“They’re ambush hunters,” McCamish explains. “The females weave a web around the hole to their burrow that’s sensitive to the touch. If an insect comes across it, the spider pounces and kills it with their fangs.”

Same spiders, different lives

Males and females lead very different lives. Females tend to stay near nests, hunting, feeding and growing. They can live up to 25 years.

Males, on the other hand, build burrows and spend around five years slowly growing and periodically molting. When it’s time to find a mate in autumn, they journey from their burrows and begin sniffing for female pheromones in hopes of finding a mate.

The females, meanwhile, come out of their burrows at night, staying nearby to spot a suitable male. If the male finds a mate and she agrees, they mate, though the joy is likely short-lived for the male. “The harsh reality is that generally after the male breeds, it passes away,” McCamish said.

Oftentimes, the female will eat her mate after it dies. However, that depends on whether she ate before mating or has enough food at the time. 

If the male fails to find a mate, it may have the opportunity to burrow for another year, or may die, depending on its molting schedule. “Generally, once the male has emerged, if it’s unsuccessful in finding a mate during the season, it will likely die due to exhaustion, ” McCamish said.

Role in biodiversity

Scientists say if you spot a tarantula, leave it be. It plays a vital role in nature. They help with the ecology of the environment, controlling insect populations and assisting with biodiversity.

Their burrows also enhance soil aeration and filter water, particularly in the desert during floods. When they abandon their nests, the burrow can serve as a home for other animals such as lizards, insects and small mammals.

Tarantulas can also help ecologists determine if an ecosystem is thriving. “If there are tarantulas living somewhere, you can generally assume the habitat is functioning,” McCamish said.

Threats to tarantulas

The spiders are also a source of food for animals like foxes, coyotes, snakes, owls, skunks and in rare cases, tarantula hawk wasps.

The wasps are an inch or two long and feature bright orange wings as well as a loud buzzing noise that has been compared to a small airplane engine when close enough to a person’s ear. “Their sting has been compared to… the second or third worst sting of any insect in the world,” McCamish said.

As for the tarantula, it’s a gruesome demise.

“They land on their back and then bite the tarantula to paralyze it. Then they lay their eggs inside it, turning the spider’s body into a living food source once the larva hatch, “ McCamish said.