You may have noticed this has been a particularly bad year for wasps. The western yellow jacket [Vespula pensylvanica] is native throughout most of the western United States. This type of wasp can be aggressive and usually show up in August and September. During the spring and early summer months yellow jackets pollinate gardens and feed on caterpillars, aphids and other insects. As food sources dwindle they become extremely aggressive in search of sugary or protein rich foods- the hot dogs and sodas of your summer barbecue’s. This taste for protein makes them unique in the insect world.
They make their homes in vacant cavities. This can include cavities of building or underground in abandoned rodent burrows, depending on the species. These pests can pack a painful sting, and for those that are allergic, these encounters could be life threatening. Yellow jackets are slow to sting but are also quite territorial. If the entrance to their nest is approached they will become very aggressive with each wasp able to sting multiple times.
A recent study published in the International Journal of Pest Management by the University of California Department of Entomology had introduced a new way of controlling these pests. Fipronil, which is the active ingredient in some topical flea and tick products for our pets can be used as an effective bait. Frontline is one brand of a fipronil based product you may have used on your pets.
In this 3 yearlong study yellow jacket colonies were greatly reduced. This works similarly to baiting traps you can purchase in stores. The foraging wasps bring fipronil laced meats back to the colony where it kills off the queen and other workers that snack on the bait. The smaller the size of proteins used allowed for small and easy to carry chunks to be brought back to the colony. This study also found that wasps have a preference of chicken or fish compared to other meats. Wet cat food makes a perfect carrier for fipronil!
If you’re finding your backyard barbecue being inundated with yellow jackets you could try what Dr. Benoit has done for us here at SouthCare Animal Medical Center. Take a small amount of cat food and mix in a few drops of Frontline. Place this high up where pets and children are not able to reach and wait for the yellow jackets to come. Over time this can help greatly reduce the number of colonies present around your home.