Ants and honey bees have a complex relationship, but in a managed beehive, ants are almost always considered opportunistic pests. A strong, healthy honey bee colony possesses robust defenses and can typically repel minor ant incursions without significant stress. However, ants become a serious threat to colonies that are weak, newly established, or suffering from issues like disease or a poor queen. The primary motivation for ants is not to prey on adult bees, but to exploit the rich, concentrated resources found within the hive. This exploitation can quickly lead to the decline or complete abandonment of the colony.
Understanding the Ant-Hive Interaction
Ants view the beehive as a highly attractive source of energy and protein, a concentrated food cache they can easily access. They are drawn in by carbohydrate-rich honey and sugar syrup, as well as protein-dense brood, including developing larvae and pupae. Ants are efficient scavengers that quickly clean up dead adult bees, spilled nectar, or crystallized honey. This initial scavenging often escalates into a full-scale infestation if the hive’s defenses are compromised.
The distinction between a nuisance and a true infestation lies in the ants’ ability to access the hive’s interior and target the live brood. When a colony is weak, with too few bees to patrol inner surfaces, ants establish foraging lines directly to the nursery areas. Once inside, they carry away the defenseless larvae and pupae, depleting the colony’s future workforce.
Environmental factors influence this vulnerability, such as a hive stand too close to a large ant nest or unsealed cracks in the hive body. The sweet scent of honey and pollen serves as a potent signal, guiding ants toward the food source. Beekeepers feeding colonies with sugar syrup inadvertently amplify this attractant. Hives placed directly on the ground or touched by vegetation provide ants with easy pathways to bypass the bees’ main entrance defenses. These factors invite massive ant invasion, which can cause a colony to abscond, or abandon the hive entirely.
Specific Ant Invaders and Their Resource Targets
A variety of ant species threaten bee colonies, with their destructiveness depending on their numbers, foraging behavior, and dietary needs. The Argentine ant (Linepithema humile) is a globally recognized pest, notorious for forming massive supercolonies and overwhelming hives. These invaders target both sugary stores and protein-rich brood, and their mass foraging lines quickly deplete a hive’s resources. This large-scale invasion often leads to the quick collapse of a weakened colony.
In contrast, fire ants, particularly the imported red fire ant (Solenopsis invicta), are more aggressive and pose a direct predatory threat. They attack adult bees at the hive entrance and actively prey on developing larvae and pupae within the comb cells. Fire ants swarm food sources, viewing the brood as a vital source of protein for their own colony’s growth. While they consume honey, their focus on the brood is exceptionally damaging to the colony’s long-term health.
Other species, such as the pavement ant or thief ant, present a less immediate danger but are still significant pests. Thief ants are tiny and can infiltrate the hive through the smallest cracks to steal honey and pollen stores. Smaller species, often called “sugar ants,” primarily target only honey and spilled syrup, posing a resource competition problem rather than a direct predatory threat.
How Honey Bees Defend Against Intrusion
Honey bees have evolved a sophisticated, multi-layered defense system to protect their nest from invading ants. The first line of defense is the vigilant guard bees stationed at the hive entrance, ready to intercept intruders. These guards use their mandibles to grasp and carry smaller ants away from the entrance, preventing them from establishing a secure foothold.
Another behavioral defense involves the bees’ use of fanning and tromping actions on surfaces where ants have traveled. Ants rely heavily on chemical pheromone trails to navigate and communicate food sources. By vigorously fanning their wings and walking repeatedly over the trails, the bees disrupt the ants’ scent markers. This collective action confuses incoming foragers and prevents scouting ants from turning into a massive invasion force.
Bees also employ propolis, a sticky, resinous substance collected from plants, as a structural defense. They use this material to seal small cracks, gaps, and openings in the hive body that ants could squeeze through. Reducing potential entry points allows bees to concentrate their defense at the main entrance, making the hive structurally secure. Some subspecies, like the Japanese honey bee, use a rapid wing-slapping technique to physically strike and dislodge ants climbing the hive walls.
Methods for Protecting Hives
The most effective way to protect a beehive from ants involves creating impassable physical barriers that prevent access from the ground. Elevating the hive on a stand forces ants to climb the stand’s legs, which can then be isolated using simple, non-toxic methods. A reliable technique is to create an oil or water moat by placing each leg of the stand into a shallow container filled with vegetable oil or soapy water. Ants cannot cross this liquid barrier, effectively cutting off their primary route to the hive.
As an alternative to moats, beekeepers can apply a thick, slippery substance like petroleum jelly or heavy grease directly to the upper portion of the stand legs. The sticky nature of these materials prevents ants from gaining the necessary traction to climb into the hive body. This method requires periodic reapplication, especially after heavy rain or dust exposure, but serves as a persistent, non-chemical deterrent. It is also important to maintain a clear perimeter, trimming any grass, weeds, or overhanging branches that ants could use as “bridges” to bypass the stand’s defenses.
Sanitation within the apiary is another powerful preventative measure against ant attraction. Since ants are drawn to the scent of sugar, beekeepers must meticulously clean up any spilled honey, sugar syrup, or wax cappings immediately after inspections or harvesting. For existing infestations, a non-toxic control like food-grade diatomaceous earth can be dusted lightly around the base of the stand or along known ant trails. This fine powder damages the ants’ exoskeletons, leading to dehydration, but is harmless to the bees.