Honey bees are highly social insects that live in organized colonies. Their primary activities involve foraging for nectar and pollen from flowering plants to sustain the colony and produce honey. Bees gather these resources from their environment, bringing them back to the hive for storage. This collection is fundamental to their survival and colony growth.
Understanding Robbing Behavior
“Robber bees” refers to a specific behavior where bees from one colony invade another hive to steal its stored honey and nectar. This is not a distinct species of bee, but rather a behavioral shift observed in regular honey bees, often older foragers. This behavior is primarily driven by resource scarcity, particularly during periods of low nectar flow, known as a nectar dearth. When natural food sources diminish, usually in late summer or early fall, bees seek alternative food sources for their colony.
Stronger colonies, with larger populations and ample forager bees, are more likely to initiate robbing as they have the numbers to overwhelm weaker hives. A vulnerable colony, perhaps due to a weak defensive system, disease, or a dwindling population, becomes an attractive target for these opportunistic invaders. This behavior is fundamentally driven by the survival instinct to ensure their own colony’s continuation during challenging times.
The Stages of a Robbing Attack
A robbing incident typically begins with scout bees from a strong colony locating a vulnerable hive, often drawn by the scent of honey or exposed resources. These scouts assess the target colony’s defensive capabilities, looking for signs of weakness or an easily accessible entrance. Upon returning to their own hive, successful scouts perform waggle dances to recruit other nestmates, signaling the location of this new food source. The recruited bees then fly to the target hive, initiating the attack.
The initial phase often involves skirmishes at the hive entrance, where invading robber bees attempt to bypass or overcome defending guard bees. If successful in breaching the entrance, the conflict escalates into full-blown battles inside the hive. Robber bees aggressively tear open capped honey cells, rapidly consuming or collecting honey to transport it back to their colony. This intense activity can continue for hours or even days until the robbed hive’s resources are depleted or its defenses completely collapse.
Recognizing Robbing in a Beehive
Observing visual and behavioral cues helps identify robbing activity. A significant indicator is an unusual increase in bee activity around the hive entrance, often appearing frantic and aggressive. Unlike normal foraging or orientation flights, which have a more organized and playful quality, robbing bees exhibit a grim, menacing demeanor, darting around erratically. You might see pairs or groups of bees grappling, tumbling, and fighting on the landing board or in the air, a clear sign of conflict.
Robber bees may also attempt to enter the hive through cracks, gaps, or openings other than the main entrance, indicating their persistence in finding a way in. The presence of an increased number of dead bees near the hive entrance is another strong sign of an ongoing battle. Additionally, if you inspect the hive’s interior, you might find large, jagged wax crumbs, distinct from the smaller, cleaner holes made during normal honey consumption, as robbers hastily rip open cells. Bees leaving the robbed hive may appear heavy with honey, often flying closer to the ground before ascending, unlike typical foragers.
Consequences for Bee Colonies
Robbing behavior has severe consequences for both the robbed and robbing colonies. For the attacked hive, the outcome is frequently devastating, often leading to significant loss of stored honey and pollen, which are vital for colony survival, especially through winter. The intense fighting results in substantial bee casualties, including the potential death of the queen, which can lead to the complete collapse and abandonment of the colony. A weakened colony may also become more susceptible to other pests and environmental stressors.
While the robbing colony gains resources, it also incurs risks. Robber bees face high mortality rates during confrontations with defending bees. A significant concern is the transmission of diseases and parasites, such as Varroa mites or American foulbrood, from the infected robbed hive to the healthy robbing colony. This can introduce new health challenges to the successful invaders, potentially weakening their own colony in the long term. The increased aggression and foraging intensity also place a metabolic strain on the robbing bees, potentially shortening their lifespan.