10 Common Wasps & Hornets in California (ID Guide)

What types of wasps, hornets, and yellowjackets live in California?

Types of wasps in California

It’s no secret that these insects are the leading cause of screaming at outdoor events! Most of the species below can’t resist investigating a soda or sugary treat. πŸ™‚

Despite their negative reputation, wasps and hornets have fascinating lives. In addition, many are beneficial because of the amount of pests they eat in your yard. They are also important pollinators!

But you do need to be careful around most types of wasps and hornets, especially if you approach their nest. They can become VERY aggressive when defending their home.

10 COMMON Wasps & Hornets in California:

#1. Bald-faced Hornet

  • Dolichovespula maculata

Also called the Bald-faced Aerial Yellowjacket, Bald-faced Wasp, Bald Hornet, White-faced Hornet, Blackjacket, White-tailed Hornet, Spruce Wasp, and Bull Wasp.

Types of hornets in California

  • They have black bodies with ivory markings on their faces, legs, thoraxes, and abdomens.
  • Look for three white stripes at the ends of their bodies.

Bald-faced Hornets are named for the ivory markings on their face. Despite the name, these insects aren’t true hornets. They’re actually a type of yellowjacket.

Bald-face Hornets don’t have a pleasant reputation in California.

They aggressively defend their nests and can sting repeatedly. But while their appearance and nests can be scary, they’re pretty handy to have around (as long as the nest isn’t close to human habitation).

First, the adults feed on nectar and help to pollinate flowers. In addition, they also kill and eat other types of yellowjackets! Sometimes, in early summer, a nest will be so full of yellowjacket remains that it will have a yellowish cast! Unless their nest is somewhere you’ll come into contact with it, it’s best to leave them be.

I’m sure you have spotted one of their nests before. They are large, papery, and football-shaped. The queen builds these nests by chewing wood material and mixing it with her saliva to make a paste.

Types of hornets in California

Bald-faced Hornet queens usually hang their nests from shrubs or trees. Sometimes, they’ll use other spots, including rocks, buildings, and other artificial materials. The queen typically continues creating workers into the summer until the nest has 100 to 400 individuals!

#2. European Paper Wasp

  • Polistes dominula

Types of wasps in California

  • Black with prominent yellow markings.
  • They have thin waists and orange-tipped antennae.
  • Their legs dangle as they fly.

These wasps’ bright yellow and black coloration means that they’re often confused with native Eastern Yellowjackets. However, European Paper Wasps are an invasive species in California. Unfortunately, they are now widespread, and researchers have found that they often outcompete native paper wasps and negatively affect caterpillars like the Monarch butterfly.

One of the reasons they have spread across North America is because of their adaptability. European Paper Wasps will inhabit almost any habitat, including urban and suburban areas. They often are closely associated with humans and nest on or in human-made structures. European Paper Wasps often build nests under the eaves or attics of structures or in pipes, light fixtures, boats, grills, and mailboxes.

Types of wasps in California

These wasps are known to be fairly non-aggressive. However, they will defend their nests, and stings usually occur when humans accidentally come in contact with a nest.

European Paper Wasps are omnivores. They will catch insect larvae, caterpillars, aphids, and other soft-bodied insects that they feed the young. Adults may also feed on flower nectar.

#3. Common Aerial Yellowjacket

  • Dolichovespula arenaria

Also called the Sandhills Hornet and Common Yellow Hornet.

common aerial yellowjacket

  • Black with yellow markings and smoky, clear wings.
  • They have stout bodies that are slightly wider than their heads.

Common Aerial Yellowjackets can adapt to various habitats in California. Typically, you’ll spot their papery nests on trees and shrubs, but they will sometimes build them on the side of homes in urban and suburban areas.

These wasps are formidable defenders of their nest and can sting multiple times like other yellowjackets. But this species also has another trick up its sleeve:

Common Aerial Yellowjackets can spray venom at attackers. This venom contains an alarm pheromone, which also helps alert other workers to help defend the nest.

aerial yellowjacket nest

The nest is made from saliva and chewed-up woody material turned into a paste.

These yellowjackets commonly feed high in the trees. In the spring and summer, they prey on various insects, including lacewings, lady beetles, caterpillars, spiders, flies, grasshoppers, and crickets. They will also occasionally eat young hummingbirds and carrion. Much of this protein-rich food is given to the larvae.

Later in the summer and fall, Common Aerial Yellowjackets spend more time going after sugary foods. They’re common sights feeding on fallen fruit in orchards, visiting trash cans, and hovering around sugary drinks and foods at picnics.

#4. Guinea Paper Wasp

  • Polistes exclamans

guinea paper wasp

  • They’re typically brown with yellow markings on their heads, thoraxes, and abdomens.
  • Narrow bodies, slender waists, smoky black wings, and antennae with red, black, and yellow bands.

Guinea Paper Wasps create small, umbrella-shaped nests with open combs that face downward. To protect their open nests, they typically seek out places that are protected from the rain. Often, this results in them using human-made structures and objects. It’s not unusual to see them building nests in storage sheds, mailboxes, pipes, infrequently used grills, and under the eaves of buildings.

guinea paper wasp nest

This wasp species is unique in California because ALL of the female workers can reproduce. In the event a queen dies, a worker will take her place.

This raises an important question: What makes a queen different?

Scientists have found that queens have higher glucose, fructose, and trehalose levels. These compounds act as cryoprotectants, preventing ice build-up and allowing queens to survive cold temperatures.

In part due to their small, open nests, both worker and queen mortality rates are fairly high. To cope with this, Guinea Paper Wasps have developed the interesting habit of building satellite nests near their primary nest. The colony will move to a satellite nest if predators like birds or parasites destroy the primary nest.

#5. Hunter’s Little Paper Wasp

  • Polistes dorsalis

Hunter's Little Paper Wasp

  • V-shaped yellow markings on their heads.
  • They are usually dark brown or black.
  • Alternating dull orange, yellow, brown, and black sections on their abdomens.

As their name suggests, Hunter’s Little Paper Wasps are one of the smaller paper wasp species in California. You’ll often find them in open areas like meadows, yards, or flatwoods.

The nests are open, umbrella-shaped nests the queen builds from chewed-up woody material and saliva. As these nests are so vulnerable, the queen usually selects a sheltered and inconspicuous spot, like in rock piles or hollow logs. In suburban and urban areas, the queens may build under the lower border of roofs or in dense shrubs.

Polistes dorsalis. (2023, July 31). In Wikipedia.

Adults feed on nectar and other sweet substances, including the honeydew from a fungus that affects grasses and cereals, including rye called ergot. Unfortunately, their feeding behavior also makes them vectors for this fungus, which can be detrimental to crops.

#6. Western Yellowjacket

  • Vespula pensylvanica
Vespula pensylvanica. (2023, June 1). In Wikipedia.
  • Females (workers and queens) have a yellow loop around each eye.
  • They are yellow with black markings and no hairs.

Western Yellowjackets are habitat generalists, building their nests in gardens, prairies, open forests, urban areas, parks, and meadows. Typically, they construct their nests in the ground, often using old rodent burrows or other existing holes to get started. Occasionally, they’ll nest in voids in the walls of houses and other structures.

These impressive nests are started in the spring by a queen who mated the previous fall and overwintered in a sheltered spot. The queen begins a small nest and lays eggs, caring for the larvae and foraging for materials until the first four to seven workers have emerged. After this point, the queen remains in the nest, laying eggs.

You may spot these creatures feeding on carrion or buzzing around picnic tables, trash cans, and fallen fruit. Western Yellowjackets are incredibly common to find living around people.

And unfortunately, these wasps can deliver an incredibly painful sting. Make sure you don’t wander too close to their nests, which they aggressively defend!

Another problem with Western Yellowjackets is their nests are typically underground, so it’s hard to spot one. These nests are often found in residential lawns and are inconveniently discovered while mowing the lawn. πŸ™‚

#7. Golden Paper Wasp

  • Polistes aurifer

golden paper wasp

  • Their coloration varies widely with location.
  • Northern individuals are often predominantly black with some golden coloring.
  • Southern individuals often have an almost entirely golden abdomen.

These wasps get their name from their unusual coloration, a softer golden yellow rather than the bright yellow of many other wasp species. Their scientific name, “aurifer,” also alludes to this coloration and is Latin for “gold-bearer.”

Queens start new nests in the late winter or spring. These wasps generally seek out high, sheltered locations to build.

As the name “paper wasp” suggests, the queens construct a nest from a paper-like material they make with saliva and wood fiber. The umbrella-shaped nests they create have open combs on the bottom.

The queens use the nest to hatch workers, which will help guard the nest and hatch more colony members. You may spot these workers visiting flowers, feeding on the nectar, or grabbing insects off plants, which they use to feed the colony’s larvae.

#8. Alaska Yellowjacket

  • Vespula alascensis

Also called the Common Yellowjacket.

alaska yellowjacket

  • Black and yellow bodies with yellow legs.
  • Yellow eyerings, which have dark interruptions on the tops and behind the eyes.
  • They have broad black bands leading from the base of their antennae to the tops of their heads.

Our knowledge of this species has taken some interesting twists! The Alaska Yellowjacket was first described and named by American entomologist and paleontologist Alpheus Spring Packard Jr. in 1870. Unfortunately, the information he gathered on this species was lost just a year later in the Great Chicago Fire of 1871!

After this point, the Alaska Yellowjacket (Vespula alascensis) was treated as a synonym for the similar-looking European Wasp (Vespula vulgaris). The Alaska Yellowjacket wasn’t recognized as a separate species until 2010!

Like many yellowjacket species in California, they typically build underground nests, which may help shelter them from hot or cold temperatures. They often build nests around areas of human habitation.

The adults are attracted to all things sweet, which is one of the reasons they’re often closely associated with people. Human food and garbage make for excellent food sources in addition to the nectar they gather from flowers.

#9. Apache Paper Wasp

  • Polistes apachus

Also called the Texas Paper Wasp or Southwestern Texas Paper Wasp.

apache paper wasp

  • They have dull orange-brown antennae.
  • Primarily golden brown with alternating stripes of golden brown and yellow on their abdomens.

Apache Paper Wasps are most commonly found in California in vineyards and orchards. They will also inhabit urban areas. If you observe them carefully, you’ll find they make frequent trips to drink water. It’s not uncommon to see Apache Paper Wasps using surface tension to stand on a puddle’s surface to drink.

Like many paper wasps, Apache Paper Wasps nests look a bit like an umbrella and have an open, downward-facing comb. By the end of the season, one nest may have up to 320 cells.

apache paper wasp nest

Their nests are started by overwintered, fertilized queens. Sometimes, these queens will work independently, while other times, other queens will help out, but these helpful females don’t always stay permanently. They often leave after construction to work on a nest of their own.

Since they hunt caterpillars, Apache Paper Wasps can be helpful to farmers as they provide some pest control. However, they have a painful sting, and their preference for vineyards and orchards has led to them sometimes becoming a nuisance.

#10. Western Paper Wasp

  • Mischocyttarus flavitarsis
Mischocyttarus flavitarsis. (2023, May 18). In Wikipedia.
  • Slender bodies with long trailing legs.
  • They’re generally reddish-brown with some black and yellow markings, but their coloration varies with population.
  • Yellow-brown wings.

Western Paper Wasps live in California in forests, suburban neighborhoods, and urban areas near a river or stream. They move along these river and stream openings when they’re out foraging for insects and nectar and collecting fibers to build their nest. They also gather water and take droplets back to the nest to cool it during hot weather.

These wasps may look frightening, but they’re not very aggressive. If Western Paper Wasps feel threatened, they’ll stand on their back and middle legs and point their antennae forward to warn predators. They may also make a loud buzzing noise with their wings as a further warning. While they can and may sting to defend their nests, Western Paper Wasps have the interesting habit of ramming predators with their heads rather than stinging.

Unfortunately for the queens, having their colony taken over is fairly common in this species. The queen will fight the wasp attempting to take her place, and they will bite and try to sting each other. Sometimes, if a foreign wasp takes over, the queen may flee with her daughters following her to build a new nest.

Learn about other creatures in California:

Which of these wasps, hornets, and yellowjackets have you seen before in California?

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