Cicada killer wasps, large and intimidating, are a common sight during summer. Their size and buzzing flight often lead to concerns about their potential to harm humans. This article clarifies their nature and addresses whether they pose a threat.
Understanding Cicada Killers
Cicada killers are among North America’s largest wasps, with females reaching up to 2 inches and males slightly smaller. They have a robust body, often with hairy reddish and black areas on their thorax, and a black to reddish-brown abdomen marked with light yellow stripes. Their wings are brownish or amber. These wasps are solitary, meaning each female builds her own nest, unlike communal hornets or yellow jackets.
Female cicada killers are skilled predators, hunting cicadas to provision underground nests. They paralyze cicadas with a sting, drag them to burrows, and lay an egg on the immobilized insect. Larvae hatch and feed on the cicada within the burrow. They prefer to dig burrows in loose, well-drained soil with full sunlight, such as lawns or garden beds. Despite their appearance and hunting prowess, they are not aggressive towards humans.
Their Sting and Interaction with Humans
Only female cicada killers possess a stinger, a modified egg-laying organ. They use this stinger almost exclusively to paralyze cicada prey. Male cicada killers, while exhibiting territorial behavior like “dive-bombing” or hovering, lack a stinger entirely and are harmless to humans. Their intimidating displays are usually an investigation, not an attack.
A female cicada killer rarely stings a human unless directly provoked or mishandled. This might occur if she is accidentally stepped on, grasped, or becomes entangled in clothing. Unlike social wasps that aggressively defend nests, cicada killers do not have the same nest-protecting instincts.
When a sting occurs, it is described as mild, often compared to a pinprick or scratch, causing localized pain. On the Schmidt Insect Sting Pain Index, their sting rates low, indicating less pain than a honey bee. As with any insect sting, an allergic reaction is possible, but severe reactions are uncommon.
Coexisting Peacefully
Cicada killers are active during summer, typically July to September, coinciding with cicada emergence. Their presence is temporary, lasting only for their breeding season. These wasps offer a benefit by helping to control cicada populations, which can damage trees. They also feed on flower nectar, contributing to pollination.
To avoid provoking cicada killers, do not swat at them, attempt to catch them, or disturb nesting areas. Observing them from a distance is the best approach. If nests are in high-traffic areas where accidental contact might occur, intervention may be considered. However, given their short active season and docile nature, professional removal is often unnecessary.
Maintaining a thick, healthy lawn can discourage nesting, as they prefer bare or sparsely vegetated soil. For most, cicada killers pose little threat and can be safely ignored.