Right in Our Backyard
Who/What Kills The Cicada Killers?
By Bill Lawyer
Before we answer that question, we have to answer the question of what is a cicada killer? And why should we care about that anyway?
For one thing, within the last few days I’ve spotted a number of areas where there seem to be swarms of the large-bodied insects on people’s lawns and even by the sandy walking path along the beach at Rye Town Park.
These large, ominous-looking insects may seem to be planning their attack on us innocent by-standers any minute, but nothing could be further from the truth, because cicada killer wasps are only interested in cicadas. And even then, their goal is not to kill the cicadas, but to bring them back to their nests, where they will become food for the cicada larvae.
So let’s look at the entire food chain, starting with the cicadas themselves.
Cicadas are the buzzing insects we start to hear in our backyards a week or so after the fourth of July. You likely know that there are numerous species of cicadas, classified by how long they live in a larval state before changing into the adults making all that noise. There are 1-year, 3-year, and so on species.
Environmentalists theorize that having species emerge at different intervals makes it difficult for the cicada killers to do serious damage to the species overall. Proliferating the cicadas would result in damage to the trees and shrubs where they are born, so regulating their numbers is a good thing.
As insects go, cicadas are large, heavy creatures, and they look somewhat scary in their own right.
The swarms of cicada killers that we should look out for are actually in the ground or on trees, following the unmistakable buzzing sounds of the cicadas, which are signaling that they are looking for mates.
Scientists note that males aggressively defend their perching areas on nesting sites against rival males, but they have no sting. Although they appear to attack anything that moves near their territories, male cicada killers are actually just investigating anything and everything. If handled roughly, females will sting, and males will jab with a sharp spine on the tip of their abdomen.
The intertwined ecology of cicadas and cicada killers are more than enough for hundreds of Ph.D. theses. The most recent review of these species’ biology is found in the posthumously published comprehensive study by noted entomologist Howard Ensign Evans.
Maybe you’ve already been wondering: what keeps the population of cicada killers under control? As is often the case, the primary predators often go along unnoticed. That’s because these predators are a variety of minuscule wasps, which come in a variety of colors, with velvet-like textures. The most common are known as the velvet ants, even though they are actually wasps. They get the “velvet” part of their name from the very fuzzy females, which are wingless and often brightly colored.
While they are much smaller than most cicada killers, they follow the same path in terms of laying eggs in the host larvae, to be used to carry on the next generation.
We human students of wasp behavior can learn a lot about the way that climate change can result in unintended consequences of trying to get rid of what are basically harmless insects.
This was the lesson that we learned years ago when the gypsy moths were destroying forests in the Northeast. Eventually a fungus came along and restored a balance.
Let’s be respectful of cicadas, right in our backyards.