Phil Hannay, Insect Ecologist and Director of Termseal Australia, explains the reasons why honey bees swarm and cause alarm for homeowners.
Since their arrival in Australia via the Second Fleet, honey bees (Apis mellifera) have become integrated in Australian agriculture. They are responsible for both honey production and the pollination of crops. However, there is a public perception that they are a pest due to adverse publicity, mainly generated by countries overseas because of “killer bees” that are a genetic cross of two subspecies not found in Australia.
There has been a massive increase in backyard beekeeping in urban areas, partially due to the advent of easy-to-use honeycomb-harvesting products such as Flow Hive. With an increasing number of hives, there is also an increasing number of swarming events, with calls to pest control companies increasing as a result when these swarms take up residence in unwanted locations. Managing bee populations means understanding the bees’ swarming gene.
During the warmer months, when food sources become more abundant, numbers increase in the hive and the queen runs out of room for egg laying and honey storage. This situation can trigger the swarming gene in the queen, who commences a recruitment drive to take a large number of adult bees from the hive, around a third to half. The swarm, with the queen, will leave the hive and will bivouac in close proximity, generally up to 100 metres away, on a low bush or high branch. Before leaving the hive, the bees fill their honey stomachs (food and water storage pouches) with nectar; this is one reason why they are not particularly aggressive at this time. The homeowner may find a swarm in their yard during this period.
The field bees will venture out from the swarm in an earnest search for a new home. They will consider any place that provides shelter, protection and space, which they accurately measure. Once a potential new home is found they will return to the swarm where the message about what they have found is conveyed to the other bees via a type of ‘waggle’ dance. This physically explains the direction, distance and size aspect of the potential new home. Other field bees will return and provide the information as to what they have found. Until consensus from the entire swarm is reached, no new home will be selected. I have seen some swarms sit for several weeks before consensus is reached.
Once consensus is gained, the queen and the swarm will leave for their new home where they will immediately begin building the hive for nectar and pollen storage as well as egg laying. As a pest manager, having to deal with concerned homeowners is not easy; they want the bees gone. However, these bivouacking swarms should not be destroyed but placed into boxes for re-deployment. This can be easily achieved by connecting with a local beekeeper who is always on the lookout for bee swarms (see box below).
If a bee hive is located in a wall cavity – stop and think! If you dust or spray the cavity you will kill the bees, leaving nothing but the brood, which will attract small hive beetles. They will eat the rotting brood and tunnel the honeycomb, causing the honey to run, which in turn attracts blowflies and in turn their larvae. You will not only have the smell from maggots, rotting brood and the slime from the rotting honey, but the slime will also run under floor plates into the home.
We don’t recommend the destruction of hives in the wall cavity unless absolutely necessary. In most cases, cutouts work best, whereby a section of the wall is removed allowing the hive to be relocated using a box. The wall cavity can be cleaned and the wall repaired. Old nesting sites are attractive to new swarms, so following the removal of a nest, we recommend the use of weeper stoppers and protecting roofs and eaves by filling holes, gaps and fissures in masonry and cladding.
Whilst honey bees are largely considered beneficial insects, they can certainly be a pest and a safety concern around homes and public buildings. However, given the media focus on the impact of insecticides on global bee populations, and the desire to avoid any negative publicity, relocating problem bees rather than using chemical control methods achieves a satisfactory outcome for all concerned.
Safe removal of honey bee swarms
The organisations listed below should be considered the first point of contact to arrange the safe removal of a swarm:
Phil Hannay, Insect Ecologist, Termseal Australia