Other venomous animals (North of Mexico)
Social Insects (Bees, wasps and ants)
Insects of the order Hymenoptera kill many more people than all other venomous animals combined each year in the United States (Forrester, Weiser & Forrester 2018).
Although often called "social" insects because many species live in colonies, many members of Hymenoptera are solitary. And while some species are stingless, many have venomous stingers that they use for defense of themselves and their colonies and a few use their sting to paralyze other invertebrates to be used as food for their larval young.
Social insects sting people for two reasons, either to protect themselves or to protect their nests. An individual bee or wasp buzzing around you is usually attracted to bright colored clothing, sweet-smelling perfume or cologne, or (especially in hot dry places) your sweat or some beverage you're drinking. They generally lose interest as soon as they figure out that you're not a flower other food source, so ignoring them or gently waving them away is the safest response. Swatting at them violently is likely to provoke a sting and crushing a bee or wasp releases pheromones (chemical signals) that can cause others to attack.
But attack and stings by many insects occurs when we bother a nest or hive. Although Africanized honey bees are well known for being hyper-defensive of their hives, some other social insects will respond in large numbers to any perceived attack on their nest. So spotting bee, wasp and ant nests and avoiding them is key to preventing stinging attacks by lots of insects. In particular, watch for individual insects going in and out of holes or cracks. A nest containing thousands of honey bees (Apis mellifera) or yellowjackets (family Vespidae) can be concealed behind a small hole with only an occasional insect flying in or out. The same hazard exists with some ants, especially red imported fire ants (Solenopsis invicta) and native harvester ants (several species of the genus Pogonomyrmex), although their nests in the soil are often easier to spot. While some types of ants inflict a painful bite, some, like fire ants and harvesters, are also equipped with an abdominal stinger that injects venom, just like stinging bees and wasps.
What makes social insects so dangerous to humans is the fact that up to two percent of people are dangerously allergic to insect stings (Lieberman et al., 2006). And acute allergy, known as anaphylaxis, can be quickly life-threatening. For an allergic person, only one sting is needed to initiate a potentially lethal reaction. Early red flags include itching, hives, difficulty breathing, "thick-tongue" sensation, nausea, and feeling faint. Any of these symptoms require quick decisive action, as waiting to see if it gets worse is a very bad idea. Call 911 and get paramedics on the way.
For first aid measures and more information about insect stings, check out the Mayo Clinic website.
And go to the Carl Hayden Bee Research Center website for dependable information on Africanized honey bees.
Ground-nesting wasp nests may be difficult to spot, like this hole in the leaves (left) that's smaller than a tennis ball. But just a few wasps coming and going (right) usually signals the presence of hundreds or even thousands of wasps ready to defend the nest. Give this spot a wide birth!
Not all feral honey bee hives are this obvious.
Many solitary wasps like this two-inch "tarantula hawk" hunt for spiders and other arthropods to feed their young.
Velvet "ants" are actually wingless female wasps that can inflict a painful sting. They move quickly, are less than an inch long, and various species are brightly colored.
Harvester ants, some nearly one-half inch long, can inflict a dangerous and painful sting, just like many bees and wasps.