Yellowjackets enjoy picnic treats like applesauce in October.
If this episode of Bug of the Week reads like a public service announcement, well, that’s because it is. While our primary goal is to demystify insects and their relatives and revel in their curious and marvelous behaviors, every now and then something buggy pops up that warrants timely attention. Earlier we provided information to thwart mosquitoes around the home and landscape, and a couple weeks ago we addressed the autumnal invasion of brown marmorated stink bugs. This week, we aim to help you avoid a nasty surprise at your October picnic. Recently, I heard an unnerving tale of someone who took a swig from a soda can and imbibed a yellowjacket. Fortunately, the angry vespid only stung the surprised victim’s tongue and not her throat before it was ejected from her mouth. Luckily, she only suffered a swollen tongue and not a life threatening occlusion of the throat.
Yellowjackets are among the most aggressive of all stinging insects in Maryland. During late summer and early autumn, yellowjackets operate at a fever pitch as workers try to gather food to maximize the production of brood back at the nest. Unlike the nests of honeybees, yellowjacket nests contain no honey or pollen. At sunny October picnics and tailgating parties, yellowjackets will visit plates and battle you for bites of barbecued chicken and sweets. Meaty protein and carbohydrate rich foods will be taken back to the hive by the workers and fed to the developing brood of yellowjacket larvae.
The natural prey items of yellowjackets are other insects such as caterpillars and beetles that plague garden and landscape plants. In this regard, yellowjackets are highly beneficial. However, by late summer and early autumn colonies may contain thousands of marauding workers and nests are often about the size of a football. Under extraordinary circumstances, nests may persist for more than one year and become enormous. There are reports of monster yellowjacket nests in southern states reaching the size of a “Volkswagen Beetle”.
Caterpillars like this fall webworm are important natural sources of protein for yellowjackets.
In late summer, back in the nest the yellowjacket assembly line switches from production of workers to the production of queens and drones. Foraging occurs at a frenetic pace. Queens produced in autumn leave the nest and seek protected locations under the bark of trees or in other outdoor refuges to escapes the ravages of winter, before founding new colonies with the return of spring. You can learn a bit more about yellow jackets in a previous episode entitled “Be careful around yellowjackets: Eastern yellowjackets, Vespula maculifrons”.
Bumble bees and honey bees are also on the prowl for sugar sources during the waning days of autumn. Carbohydrates obtained from flowers, fallen fruit, or open cans of soft drinks are on the menu. Liquid sugar sources are imbibed and stored in the bee’s specialized honey stomach. Carbohydrate rich liquids are fed to brood, other bees, or turned into honey upon returning to the hive.
What can you do to avoid confrontations with these stingers? Choose picnic and tailgating spots carefully. Do not set up your picnic near a trash container or dumpster where yellowjackets and bees may be foraging. Bring a covered container to stow your trash and to keep hungry foragers away from food scraps and partially filled drink containers. Keep food covered. This reduces recruitment by foragers that tend to accumulate around accessible food sources. If yellowjackets try to sneak a bite of your food, gently brush them away rather than engaging in hysterical slapping and squealing. Quick movements and non-lethal blows can incite painful attacks. Drink from clear bottles or pour drinks into clear cups. This will allow you to observe stinging insects doing a backstroke in your drink before you slurp them into your mouth. Bees and yellowjackets often find their way into pop-top cans and can disappear down your gullet without being seen. Instead of canned drinks, try juices in drink boxes equipped with tight fitting straws. These are great for children who often place canned soft drinks down for a while before returning to finish them.
Oh, and you may have heard that yellowjackets are capable of multiple stings. This is only partially true. Contrary to common belief, some yellowjackets have barbed stingers like our friends the honey bees. Yellowjackets may lose their stingers and be eviscerated in the process. If you are stung, apply ice to the site of the sting to reduce swelling and pain. If you are stung and experience symptoms such as shortness of breath, difficulty breathing or swallowing, hives on your body, disorientation, lightheadedness or other unusual symptoms, seek medical attention immediately. Enjoy outdoor feasts with friends and families on these glorious October days, but remember that taking a few precautions can help you avoid nasty surprises from yellowjackets and busy bees.
After six laps in an unattended soda can, this little bumble bee was ready for a rescue. Note the lack of aggression and the grateful look on the bee’s face.
References
We thank Dr. Shrewsbury for imbibing a yellowjacket and living to tell about it. We also thank Dr. Nancy Breisch for sharing her expertise and knowledge about stinging insects.