Spiders in California: 7 Species to Look Out For

California garden spider
Photo by Sean Paul Kinnear on Unsplash
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With its sprawling national parks, incredible sightseeing opportunities, and gorgeous golden coastlines, spiders are probably the last things that come to mind when you think of California. In fact, it’s considered one of America’s most diverse travel destinations and home to some of the most iconic big cities and the infamous Silicon Valley.

As such, it might surprise you to know that there’s more than just sunshine, great food, and vibrant nightlife that tourists will need to be aware of. California is also home to a variety of spiders, but don’t worry, there are only a few in this charming state that pose any real danger to humans.

Still, prevention is better than the cure, and we’ve compiled a list of arachnids, both harmless and harmful, to ensure your golden coast stay is as revitalizing and relaxing as possible. Let’s get into it.

Flower Crab Spider

crab flower spider
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Also known as misumena vatia, the flower crab spider is a fairly common arachnid species that can be difficult to spot due to its camouflaging abilities. They’re generally white or yellow in color and earned their name as a result of their tendency to lie in wait inside flowers for bees, butterflies, moths, and other prey, which they then snatch out of the air like crabs.

Although their faces can seem intimidating, you can rest assured that these tiny spiders pose no real threat to humans, and they’re actually quite pretty since they resemble orchids. They also have their fair share of predators to contend with, including birds, ants, wasps, and bigger spiders. 

Other interesting tidbits about this creepy crawly include their largely solitary nature,  attraction to the fragrance of flowers when choosing habitats, the fact that their mouthparts are too small to pierce human skin, their ability to see in all directions, and their love for temperate climates like California’s.

Black Widow

black widow
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Unfortunately, these notoriously dangerous spiders are quite common in California, so if you’re planning a little getaway there it would be a good idea to learn how to identify them. 

From the red hourglass markings on their abdomens to their jet black bodies, female black widows are undoubtedly the most distinctive of this species and a beauty to behold, while male black widows tend to look very different and are generally lighter in color and much smaller in size. Still, don’t be fooled, their venom packs a powerful punch. 

These spiders earned their name due to the tendency of females to eat their partners after mating, and while death from a black widow bite is decidedly rare, they are still highly poisonous to humans. People have been known to suffer from nausea, muscle aches, as well as strained breathing due to paralysis of the diaphragm after being bitten, and they could also be potentially fatal to children, the elderly, and the sick.

They’re typically found between boxes in storage spaces as well as shielded areas like attics and barns. That being said, they have terrible eyesight and catch prey, like flying and climbing insects, through vibrations in their web, so you should be fine as long as you don’t stumble through them.

Spinybacked Orb Weaver

orb-weave california spider
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Spinybacked orb weavers, also known as spiny spiders, are small, odd-looking arachnids that resemble crabs. They have colorful bodies, usually a mix of either black, white, or yellow, with red spines and white spots on their backs. 

They may have a strange appearance, but they’re quite harmless to humans, and despite their tiny stature, they’re capable of spinning awe-inspiring webs in forests and woodland areas, which they eat and rebuild daily. They are also quite a few different species of this spider, and they all come in different colors.

Like black widows, female spiny orb-weavers are bigger than males in size, and they feed on their male counterparts after the mating process. They’re usually found on the leaves of trees, but can also be spotted in bushy gardens or orchards where they spin their webs and mimic the vibrations of prey, like mosquitoes, beetles, and moths, to trap and feed on them.

Some of the most interesting anecdotes about these spiders include their seismic communication, the fact that there are always knots of silk on their webs, and the anti-predator function on their abdomen which helps them avoid the dangers of predators like wasps, birds, and other spiders.

California Tarantula

california tarantula
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They may be just as infamous as black widows, but these spiders aren’t nearly as dangerous, and they’re quite popular as pets.

Believe it or not, its name originates from the southern Italian town of Taranto, where locals believed that bites from this spider were life-threatening and could only be combatted through a dancing ritual. Victims would perform a dance called the Tarantella until they passed out, and this is how the ‘Tarantula’ name came to be.

While their large hairy bodies and legs might make them appear menacing, and they could still bite if threatened, their venom is actually even milder than a honeybee’s. Consequently, they pose no real threat to humans. Needless to say, it was most likely the bite of a black widow species instead that made people sick back in the day.

It’s believed that there are over 850 tarantula species worldwide, but only 18 species of these big hairy spiders are known to inhabit California’s rolling hillsides, foothills, and deserts. All of California’s tarantulas are nocturnal ground-dwelling hunting spiders who only come out of their burrows at night to hunt for small lizards, mice, scorpions, spiders, and other prey. This includes the “Johnny Cash Tarantula”  which was given this name after it was discovered near Folsom Prison. 

Fishing Spider

fishing spider
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Fishing spiders are frighteningly large arachnids who are usually brown or tan in color with light brown bands on their abdomen and have the ability to run on the surface of water. They’re harmless for the most part, and while they are venomous they aren’t particularly aggressive and only pose a threat if you’re allergic.

These spiders have velvety hydrophobic hair all over their bodies which allows them to thrive in aquatic environments like freshwater near lakes, ponds, or wooded areas. They’re remarkably fast and have the ability to prey upon fish up to 42 times bigger than them, although they primarily eat small aquatic insects. 

They’re also often mistaken for wolf spiders due to their similar appearances, but they can be distinguished by their bigger bodies and the arrangement of their four differently sized eyes. Another interesting fact about these solitary arachnids is that female fishing spiders’ can produce a thousand eggs at one time.

Should a member of your holiday crew have arachnophobia, and you stumbled upon one of these intimidating critters in a boathouse or near the edge of the water, have no fear, they can easily be ushered into a jar or other container and released back into nature.

Cellar Spider

daddy longlegs
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Often referred to as ‘daddy longlegs’, cellar spiders take residence in damp, dark locations like cellars and basements, as their name implies. Cellar spiders are also sometimes referred to as ‘vibrating spiders’ due to their habit of vibrating their webs rapidly, presumably to confuse or deter predators, when they feel threatened.

They’re generally pale yellow, light brown, or gray in color, and most cellar spiders have disproportionately long legs. Despite their somewhat creepy appearance, they are absolutely harmless. As a matter of fact, they don’t even have fangs long enough to penetrate human skin. 

Having said that, getting rid of their webs in a corner of your garage, for example, can be somewhat of an annoyance since these spiders have a tendency to spin new webs onto existing webbing. 

Black and Yellow Garden Spiders

black and yellow garden spider
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These striking spiders are quite a common sight, not only in California but all over the United States. They belong to the orb-weaver family of spiders and they’re known to go largely unnoticed for most of the year, but build bold and imposing webs, which can be used for pest control, in the fall. 

As their name implies, their bodies often feature black and yellow coloring, while their bodies are oval-shaped with very long legs, and they prefer to reside in sunny locations with vegetation like gardens, meadows, or fields. However, it should be noted that only female garden spiders have this color combination, and male garden spiders tend to be a much duller red-brown shade. 

Black and yellow garden spiders are also known by a variety of other names, including zipper, banana, and writing spiders, as a result of their elaborate silk woven web detailing.

Although they may seem fairly threatening to us, these spiders are actually quite vulnerable to predators due to their bad eyesight and birds, lizards, and even some wasps will eat them if given the chance. Like cellar spiders, they also have a tendency to vibrate their webs in an attempt to repel predators when threatened, and they pose no threat to humans.

Are there any dangerous spiders in California?

There are a few varieties of poisonous spiders that can be found in California, these include black widows, the brown widows, the yellow sac spider, and the desert recluse. Still, it’s uncommon for humans to get bitten by these species, and if they do, the bite will likely hurt no more than a wasp sting and can be treated easily. 

Are there big spiders in California?

There is one native tarantula of California, the Aphonopelma, or California Tarantula, and some can reach up to six inches in length – the size of an average banana. They may look terrifying, but they’re generally harmless. Still, that doesn’t mean they won’t give you a fright when you find them in your pool filters.

Do California house spiders bite?

House spiders in California can bite humans but their venom is not toxic and generally harmless. A bite can hurt but often won’t need treatment and some house spiders, like cellar spiders, don’t even have large enough mouths to clamp down on human flesh. House spiders build many webs and love corners of rooms by windows where they can access houses. They might be a nuisance but they cause no harm and are very timid. They can even catch pesky flies and mosquitos for you in their webs, so having them around can be a positive.  

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Esmé is an English literature graduate and freelance writer. Originally from London, Esmé is lucky enough to call Bali home. Her travels have taken her from the far corners of the East to the islands of the Caribbean. When she's not writing, you'll find her lying on a beach somewhere, lost in a crime novel.