Last updated on September 21st, 2023 at 12:13 pm
No, bees do not eat caterpillars. Wasps and hornets regularly predate on caterpillars and can often be mistaken for bees.
Bees species, excluding the Vulture bee, feed on a predominantly pollen and nectar diet. This can lead to close encounters with many other insects in the stems, leaves and flowers of plants.
Generally, most bees will prioritise gathering resources for their colony and ignore other insects they encounter. Some rare cases exist when bees interact with other insects, but this does not extend to caterpillars.
You can learn more about some insects bees interact with inside our short read on how bees eat Aphid’s honeydew for sustenance.
Despite this apparent lack of interest in caterpillars, bees have more of an effect than you might think.
Testing How Bees & Caterpillars Interact
With bees and caterpillars spending so much time foraging in the same area, it posed the question, do these two very different insects affect each other?
Two researchers from the University of Wuerzburg, Jürgen Tautz and Michael Rostás, began researching the links between bees, caterpillars and plants.
The two researchers used the University’s botanical garden as the site for their research. They used two large 2m squared cubic tents to house ten soybean plants or ten bell pepper plants.
They added ten third-instar beet armyworm caterpillars (Spodoptera exigua) to each plant. One tent was left to succumb to the caterpillar’s voracious appetite with no external influence.
This tent and its occupants would control the test to measure against the results achieved inside tent two.
The second, much more interesting tent was exactly the same except for two key differences: the tent was connected via some tubing to a beehive containing a colony of western honeybees and two feeders containing 2.5 molar sugar solutions were mounted at half-plant height above ground in the two corners of the tent.
Why Bees Affect Caterpillars & Plant Damage
The results returned by this very simple experiment highlighted some fascinating correlations between bees and caterpillars. Tent two, which contained the colony of honeybees, looked completely different to tent one.
The plants inside tent two had experienced approximately a third of the damage of those inside tent one. The clear conclusion here is honeybees stop caterpillars from eating so much, but why?
The researchers conclude that this stems from a case of mistaken identity.
Wasps and hornets pose a serious threat to caterpillars. They use caterpillars’ bodies as incubators for their young or simply as a food source, the stuff of horror movies!
The tissue that makes up a caterpillar’s body is packed with proteins, perfect for wasps and hornets to feed on.
The theory is that bee’s similarities to wasps, and hornets means that caterpillars mistake them for predators and act accordingly.
How Do Caterpillars Identify Bees As A Threat?
Some species of caterpillar, including those of the beet armyworm (Spodoptera exigua), are equipped with tiny sensory hairs that cover the length of their body.
These hairs can sense vibrations created in the air like bees, wasps, or hornets flap their wings. This sensory cue will lead to caterpillars dropping off the plant to avoid being eaten or injected with larvae.
*Extra reading – Take a closer look at a bee’s diet and how they get all the nutrients they need to survive.
Undisturbed, caterpillars will eat virtually constantly, so the regular flights undertaken by the bees led to a significant drop in consumption of plant matter within the tent.
After assessing the plants thoroughly, the researchers identified that the plants with a honeybee presence had 69.3% and 60.6% less foliage damage than the control test, staggering results.
So, in answer to the question, do bees eat caterpillars? It’s a resounding no, but they do affect how much caterpillars eat when they’re around.
Looking for another fascinating deep dive into the magical world of bees?
Check out our next short read on do bees eat butterflies for more interesting facts and knowledge about bees.