Written by: Shelby Paxton
We’ve all been there, enjoying a nice meal outside or sitting on a park bench when all of a sudden, a blur of black and yellow starts charging at you, chasing you around and buzzing up a storm! Moment of relaxation ruined. Now who could be behind this? Well, more often than not, it’s yellow jackets.
Lets make something clear before we begin, yellow jackets are not an individual species, the term ‘yellow jacket‘ refers to all predatory eusocial wasps, within the genus Vespula and Dolichovespula. Most yellow jackets are black and yellow, but there are some exceptions, for example, the bald-faced hornet is white and black. The 3 most common yellow jackets species found within Ontario are the aerial, German, and common yellow jacket.
Yellow jackets are an insect within the hymenopteran order which includes bees and ants. They are not hornets, ‘hornet’ is a name given to the largest group of wasps. In other words, all hornets are wasps but not all wasps are hornets.
Yellow jackets have a couple of lookalikes including honeybees and flower flies. Honeybees are much more fuzzy, docile, have thicker waists, can only sting once and are generally slower fliers. Bees can only sting once due to their barbed stinger which gets stuck in their target’s skin, forcing them to rip out their stinger. Meanwhile, Yellow jackets have a smooth stinger, so it doesn’t get stuck in their target’s skin. Flower flies differ from wasps in a couple of ways, their eyes are much larger and wrap around their heads, they hover, have 1 pair of wings, and tend to be a lot smaller than wasps.
Yellow jackets are not picky when it comes to food, they are omnivorous and will feed on fruits, nectar, carrion, and their primary food source, other invertebrates. This is why you will commonly find them in garbage cans and frequenting picnics, they are just looking for their next meal. Yellow jackets will also search for food within 1 mile of their nest.
Yellow Jackets do not attack unprovoked. This may sound great at first, except they have a nasty habit of taking things the wrong way. They are territorial and will fiercely defend their hive if they believe you are too close and will take you moving your delicious food away from them quite personally.
Individuals have different roles within a eusocial community, for yellow jackets, they have the queen, worker, and drone. Each of the roles are visually different, for example, queens are larger in size and have different patterning on their abdomen. Now if you’re like me, one of the first things that you would think when you hear the queen is much larger, is if her sting is more dangerous. This is not the case, the queen’s stinger may be bigger but it’s not any more dangerous to us than a worker wasp’s stinger.
What does the queen wasp do for the hive? Her main role is to lay eggs and construct new nests. She creates these nests in sheltered locations, unfortunately, that usually entails barbeques, porches, and fences, although some queens do makes their nests underground. She mixes saliva, and wood fibre into a pulp that she uses to build the nest. Another one of queen’s jobs is to survive the winter so that she can start a new colony in the spring. Queen wasps must find a place to hibernate while all of the drones, and workers will perish. Queens will generally hide in small spaces to protect themselves from the colder temperatures. However, many of these queens will become a hungry spider’s next meal or die of starvation from being woken early by a warm winter.
Now, some of you might be wondering how does a wasp become a queen? It starts off when a queen picks an egg containing a female wasp, these eggs are moved to a larger hole in the nest, signalling that they should be given special care that allows them to develop into a queen[9,10]. Lastly, Drone and worker wasps get their personality from the queen, for example, if the hive is under attack and the queen refuses to leave her nest, so will all of her young but if she is more aggressive, and attacks, her young will fight back with her.
The next role is the drone wasp, these wasps are all male and their primary role is to mate with the queen. No need to worry about drones ruining your picnic, they lack stingers. The queen’s eggs aren’t always fertilized, if this is the case, the young will develop into drones, fertilized eggs will always be female workers or queens.
The last role is the worker, interestingly, they may not be able to reproduce, but they do have genes relating to reproduction that promotes a nurturing behaviour towards juveniles. In fact, these reproductive genes are expressed more in workers than they are in queens. Workers are also the pollinators of the hive, drones and queens do not partake in pollination. Instead, these wasps search for and kill other invertebrates to feed their young a protein-rich diet. Workers are also in charge of maintaining and constructing the hive once the queen begins laying eggs.
Despite all the grief yellow jackets can cause us, they are beneficial to have around. As mentioned earlier, they pollinate flowers, promoting plant growth and floral biodiversity. They also help us to deal with agricultural and garden pest species like caterpillars and flies. They even help to break down carrion like road kill.