The Most Dangerous Insects and Pests in California

House In California


When most people hear the word ‘pest,’ they immediately conjure up an image of insects swarming in the walls, several mice scurrying away under the kitchen sink, or something equally gross and irritating but rarely causing bodily harm. However, although some pests appear to be generally content with causing property damage or being a general nuisance, several others can be dangerous and life-threatening. 

There are a lot of misconceptions about what the word “pest” means, so before exploring a list of the most dangerous insects and pests in California and what makes them dangerous, let’s take a look at what a pest is.

Technically Speaking, What Are Pests?

The term “pests,” as far as this article is concerned, refers to any animal that causes damage to human or human concerns. This term is usually used for animals or insects that cause damage to crops on farms and other animals and those that cause damage and constitute nuisances to proper living conditions.

This definition is important because a pest might not always be a pest. What does that mean? Well, termites in their natural environment (in the woods or soil) cannot be strictly classified as pests. However, when they invade your home and eat up your furniture, you can definitely classify them as pests. So it is possible for an organism to be classified as beneficial in one instance and then be classified as a pest in another different situation. 

As mentioned earlier, while some pests are relatively harmless or incapable of harming you (directly or indirectly), others are much more dangerous. So it is important you can identify these dangerous pests so you can call for appropriate help and pest control intervention when needed. 

Most Dangerous Insects and Pests In California 

Here is a list of the most dangerous insects and pests in California. If you happen to spot one of these, your pest infestation situation has become very serious, and you should call for pest control help immediately.


Mosquitos may seem harmless at first, as their bites usually appear to be just an itchy annoyance. However, mosquitos are well known for carrying potentially deadly viruses such as the West Nile and the Zika virus, making them very dangerous insects to encounter. There is also the fact that they are usually present in large numbers and increase rapidly as well, and this particular factor can make controlling them quite challenging.

Fortunately, there are several measures you can employ to effectively get rid of mosquitos from your house and the environment as a whole. These measures include:

  • Drain every bit of stagnant water around your house

Mosquitoes usually deposit their eggs into stagnant water, and their larvae grow in it. One way to effectively and decisively reduce the mosquito population is to get rid of their breeding points (the stagnant water around your home.

  • Using bug repellents:

Over-the-counter bug repellents are also quite effective measures for controlling the mosquito population in your home and environment. However, these chemicals can have harmful effects, so it is usually advised to have pest control professionals handle the spraying for you if you don’t know how to.

Black Widow

Arguably the most infamous of all spiders, the black widow is easily identifiable with its pitch-black skin and bright red hourglass marking. The black widow’s venom is filled with neurotoxins that can cause muscle cramping, raise blood pressure, and even disrupt your breathing.

If a black widow has bitten you, seek medical attention immediately; and if you find one in your home, immediately reach out to pest control to help you get rid of it safely.

Bark Scorpion

Scorpions are extremely dangerous pests, so much so that they have become popular and are associated with danger. However, among this very dangerous pest type, the bark scorpion is one of the most infamous of the lot.

The bark scorpion easily distinguishes itself as a threat on sight with the way it spreads its pincers and raises its tail. If your door has just 1/16th of an inch clearance, these pesky scorpions can squeeze their way into your home.

And if the way they look is not enough to get you on the phone calling for pest control, they also have a nasty sting that can quickly turn your life into a nightmare. Common symptoms that follow a bark scorpion sting include vomiting, numbness, and severe pain. Some can also experience the feeling of repeated electrocution. 

This pest’s sting could leave you incapacitated and unable to get medical attention, so you certainly don’t want to hesitate to contact help from pest control whenever you notice or suspect they are in your home.


Although very small in size and usually regarded as harmless, ant infestations can become pretty severe and very dangerous to you. These insects multiply rapidly and are “persistent colonizers”, so you do not want them in your home. There is also the fact that some species of ants can get big enough to be more than just a minor inconvenience. Ants also bite, and, according to the pain index, some ant species have bites that can cause you excruciating pain.

Contact Us

If you find that your home is besieged with dangerous insects, don’t hesitate! Contact Preventive Pest Control today and see for yourself why we have become one of the most trusted names in pest control!

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