Alert: Northern Giant Hornet
Washington State Department of Agriculture (WSDA) announces a pest alert for the northern giant hornet. In December 2019, WSDA confirmed the identify of this invasive hornet found in Whatcom County. It's the first detection of this species in Washington. WSDA asks that you keep a lookout for the northern giant hornet and report any sightings.
Learn about the northern giant hornet and human health issues.
Bees and wasps are commonly encountered, especially during late summer when they are most abundant and more active. In nature, these stinging insects play a beneficial role, particularly as predators of pest insects and as pollinators.
Understanding the basic differences between bees and wasps can help you identify and control potential problems and prevent unwanted stings.
The most commonly seen bees in Washington are the honey bee and bumble bee. Bees feed on pollen and nectar, and their foraging activity help ensure the pollination of flowering plants. It is estimated that one third of our food supply depends on insect pollination, most of which is done by bees. Bees have robust and fuzzy bodies compared with wasps, which serve to enhance their pollen gathering.
Honey bees live in perennial colonies that nest in crevices of large trees, voids of building walls, or other protected areas. Unlike honey bees, bumble bees establish new colonies each spring. They prefer to build their nest in abandoned mice burrows, small cavities in building walls, or other similar spaces.
Both the honey and bumble bee can sting and will aggressively defend their colony. While foraging, bees are rather passive and rarely sting unless severely provoked. When a honey bee stings, it is just once. Their strongly barbed stinger lodges in the skin, then tears from the bee's body when it flies away – this causes the death of the bee. The bumble bee's stinger however lacks barbs, so it can sting repeatedly.
Honey bees swarm when they are searching for a new home. If you find a swarm on your property or a honey bee nest is suspected, capturing a specimen or taking a good picture and getting it identified is an important step to verify what insect is actually present. If the specimens are confirmed to be honey bees, first consider contacting a beekeeper for help with the removal of the colony. A list of beekeepers in Washington who are willing to remove a honey bee colony or swarm can be found on Bee Removal Source website. You can also find assistance to remove a honey bee swarm at the Washington State Beekeeper's Association's website.
Yellowjackets (including hornets) and paper wasps are the most common types of wasps encountered in Washington. Wasps have slender bodies with a narrow waist and appear smooth and shiny. Their feeding habits differ greatly from bees. Most wasps prey on insects, including caterpillars, flies, crickets, and other pests. Although yellowjackets feed on some insects, they readily scavenge on human food and garbage. Their aggressive feeding habits can make them a serious nuisance problem, especially at picnics and campgrounds. Paper wasps do not scavenge and are rarely aggressive. However, their habit of nesting anywhere, and often in frequently used areas, creates problems.
Wasps establish a new colony each spring and almost never re-use their old nest. Both yellowjackets and paper wasps construct paper nest from chewed wood fiber mixed with saliva. A paper wasp's nest resemble an umbrella consisting of a single comb with open cells. Paper wasps commonly build nests on tree limbs, building overhangs, and beams and supports in attics of garages, barns, and sheds. They also build nests in small cavities of building walls, within metal gutters and poles, and under outdoor furniture. As for yellowjackets, certain types conceal their nests below ground in old rodent burrows, behind exterior building walls, in hollows of children's playground equipment, or other similar spaces. Other types build large, conspicuous hanging nests in shrubs, trees, or under eaves of buildings.
Like bees, wasps will sting in defense of its colony or itself. In late summer and fall, yellowjackets become aggressive scavengers, sometimes stinging without being provoked. The wasp's stinger has small barbs which do not embed in the skin. Wasps can sting repeatedly and will often do so if threatened or protecting their nest.
Don't Attract Them
- Avoid wearing bright colors or flower-patterned clothing.
- Avoid wearing fragrant perfumes, cologne, lotions, or hair products.
- Keep food and drink covered or under screens when eating outdoors.
- Clean up and dispose food and garbage properly, including decaying fallen fruit, and dog or other animal feces.
Avoid Their Attack
- Stay calm and still if a single bee or wasp is flying around. Swatting may cause it to sting.
- If you are attacked by several stinging insects, run to get away from them. Some bees release chemicals when they sting that prompt other nearby bees to attack.
- If a stinging insect flies inside your vehicle, stop the car slowly, and open all the windows.
Control Their Nest
- Identify the insect and locate its nest. If it is necessary to control them, use the least toxic and most appropriate methods available. The University of Idaho's Homeowner Guide to Yellowjackets, Bald-faced Hornets and Paper Wasps (PDF) provides additional information on management and control strategies.
- Typical wasp traps are only effective for yellowjackets, but not hornets or wasps. They do not attract paper wasps or hornets and will not help control these types of wasps. Non-toxic lures and traps for yellowjackets are described in Washington State University Extension's Yellowjackets and Paper Wasps (PDF) as well as in the University of Idaho's guide listed above.
- If insecticide sprays are used, always follow the label's instructions carefully.
- Hire a pest control company or removal services if you are allergic to stings or if nests are in difficult-to-control areas.
The bee or wasp stinger injects venom into the skin. It is this venom that causes the pain and other symptoms. Typically, symptoms are localized pain, swelling, itching, and mild redness at the sting site.
- If you were stung by a honey bee, remove the stinger quickly using gauze wiped over the area or by scraping a fingernail across the stinger. Quick removal means less venom injected.
- Never squeeze the stinger or use tweezers.
- Wash the site thoroughly with soap and water.
- Apply ice to reduce swelling.
- Take an antihistamine or apply creams to reduce itching if necessary.
- Watch for symptoms of infection over the next several days. Symptoms include increasing redness, swelling, or pain.
Allergic reactions to bee or wasp stings can be deadly. People with known allergies to insect stings should always carry an anaphylaxis kit and wear a medical ID bracelet or necklace stating their allergy.
Call 911 if any of these signs occur:
- Trouble breathing, wheezing, or shortness of breath.
- Swelling anywhere on the face or in the mouth.
- Throat tightness or difficulty swallowing.
- Feeling faint or dizziness.
- Turning blue.
Insect Bites and Stings, Medline Plus
Insects and Scorpions - Workplace Safety and Health, CDC
Pest Press - Bees, Wasps, and Yellowjackets, Washington State University Extension
Content Source: Zoonotic Disease Program