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The 3 Most Dangerous Insects in California

The bark scorpion, the most dangerous scorpion in California.

Bugs, ants, and other insects can easily become a nuisance to people in any home environment. Most do not pose any real fatal danger if people come in contact with them. On the other hand, there are other pests in California that can cause real danger. One of the best lines of defense is to identify the dangerous bugs in California and understand how and why they’re dangerous. 

Bark Scorpions

While there are many types of scorpions in California, the bark scorpion is the most dangerous. Similar to all scorpions, the bark scorpion is about 2-3 inches long from pincher to tail. They can be identified by a yellowish body with no stripes. 

When these little pests are on the prowl, they do not need a lot of space to slip under the door—it only takes about 1/16 of an inch. Bark scorpions are attracted to moisture, so they are more likely to be found in basements, attics, cellars, etc.

Scorpion Bites

Getting stung by one of these venomous pests is normally the beginning of a horrible nightmare. When you’re bitten by a scorpion bite, you may feel like you’re being electrocuted, experience severe pain and numbness, and possibly even vomit. These pests can render their victims completely immobile. If you’re bit by a scorpion, you need to go to the emergency room immediately. 

Types of Scorpions in California

  • The Arizona Hairy Scorpion has a brown body with clear/tan legs, tails & pinchers. This scorpion would be more common in Southern California, and they can be up to 7 inches long.
  • The California Common Scorpion is more clear or yellow in color. They like sand and gravel, so they may be more common in lakes or beaches.
  • The Stripe-Tail Scorpion is brown/tan with stripes on its back and tail. They like dark and cozy outdoor places, so keep an eye out for these guys when camping.

Black Widow Spiders

A female black widow spider on a spider webIt is not uncommon for even the name black widow spider to provoke fear in the hearts of anyone who encounters them in their garden or around their home. With an inky black bodice and darken red hourglass shape, these are visible signs of a black widow and that the person should move far away from these pests when they are seen. 

While not as deadly as people believe, because her venom is filled with neurotoxins, this is an instant problem for a victim's nervous system that leads to muscle cramps and high blood pressure, along with difficulty in their breathing. Once bitten, people should seek medical attention immediately.

Deer Mice

A brown deer mouseWhile not an insect, one of the most dangerous pests in California is the deer mice. Deer mice can put your family at risk by bringing bacteria, pathogens, parasites, and viruses into your home. The most dangerous illness that deer mice can transmit is Hantavirus. 

How is Hantavirus Spread

This virus is normally spread a number of different ways, including airborne particles, urine, and mice droppings. As deer mice are not social rodents, it’s unlikely they will come up to a human and bite you directly (although it isn’t impossible). The dangers of Hantavirus are not only serious, but fatal since approximately 36% of the people in the U.S. die after being infected. So if you notice signs of Hantavirus—such as fatigue, fever, muscle aches in hips and thighs, headaches, dizziness, vomiting, etc.—it’s important to see your primary care physician ASAP.