The Spiral Hives of Sugarbag Bees

Not all bees sting. There are about five hundred bee species out of twenty thousand that have lost that ability, but they do exhibit other defensive behaviors like biting or showering intruders with a rain of wax, plant resin and mud. Larger predators are often engulfed by the sheer strength of their numbers.

There are fourteen species of stingless bees that are native to Australia. Among these, the sugarbag bee or bush bee is particularly notable for the beautiful hives they make.

Sugarbag Bees

Photo credit: Tim Heard

Tetragonula carbonaria, or the sugarbag bee, tend to be smaller in size compared to other stingless bees. They are predominantly black and their bodies are covered in microscopic hairs. The sugarbag bee builds hives in a distinctive spiral pattern unique to the species. The hives are broad and flat but each spiral rises in height as they turn, giving the hive a flattened conical shape. A fully developed nest may consist as many as twenty spirals.

Carbonaria bee hives have only one entrance, which is heavily protected by guard bees and coated with a mixture of beeswax and resins. Antibacterial properties from the resin clean any pathogens from the bees as they enter the hive. The substance also keeps out predators such as ants and beetles.

It is not known why the sugarbag bee make spiral hives. It may be to make air circulation better, especially since other bee colonies are not well ventilated.

“It may be unwise to attempt to explain the adaptive significance of why this form may have evolved,” Tim Heard, an entomologist, told Live Science. “Perhaps, it is just the outcome of some random behavior or perhaps it is adaptive. A possible adaptive advantage of this form is that it is efficient use of space and also facilitates the circulation of air between the layers. But then one has to ask, why it is not more common.”

Because stingless bees can’t sting, many Australian suburban homes have these beehives in their backyard. Many of these beekeepers do not keep the bees for honey, but rather for the pleasure of conserving a native species whose original habitat is declining due to human development. In return, the bees pollinate crops, garden flowers, and bushland during their search for nectar and pollen.

Sugarbag Bees