Feral European Bees
The European honey bee (Apis mellifera) is an exotic species that was introduced into the Australian environment over 180 years ago. Honey bees were used to pollinate plants grown by early settlers for food - a task that was previously done by hand. Honey bees (managed hives) are now kept commercially for food and honey production, but feral bees have also become an increasing threat to our native hollow-dwelling fauna, particularly black cockatoos, through competition for suitable hollows, and possibly also competition for nectar.
From the original managed hives, honey bees have swarmed and become feral pests. They have now spread throughout much of Western Australia and Australia, including the semi-arid interior eucalypt and rainforests, coastal heaths, farming and grazing land and urban areas. They are a particular nuisance during summer months when they seek water to cool their hive. Feral honey bees are generally aggressive, have a tendency to swarm and they are of little value for commercial honey production or for pollination of crops. Feral honey bees also pose a future health risk to managed hives including Varroa mites, fungal diseases and Colony collapse disorder.
Feral European honey bees have become a significant problem because of the change from grass-based grain farming, such as wheat (wind pollinated), to flowering plants, particularly lupins and canola. Flowering plants produce both nectar and pollen, which has caused an increase in the numbers of feral bees as they use these areas as a major food source, swarming more frequently.
Australia’s rich native flora evolved in the absence of Apis honey bees. Consequently, our native plants are adapted to other kinds of pollen vectors such as native insects, birds and mammals. Especially important are Australia’s 2,000 or so species of native bees which are efficient and often specialised pollinators. While many native plants can be pollinated by the honey bee, others cannot and require their specific native pollinator.
At present, there are about 30,000 hives in Western Australia mostly managed by amateur beekeepers, along with thousands of feral bee colonies living in trees and other suitable nesting sites (Dept of Agriculture and Food).
Whilst conducting field work on the black cockatoos, the WA Museum has come across large numbers of feral bee hives that have taken over tree hollows. This has meant a reduction in the number of suitable hollows left for the obligate hollow-nesting species including cockatoos and other birds e.g. small parrots, Sacred Kingfisher and mammals e.g. possums and bats. A number of black cockatoo chicks, honeyeaters and owls have been found dead in these hollows, often stung or engulfed by swarming feral bees.
Currently, the WA Museum is documenting feral bee hive locations when discovered during field monitoring. Using a Global Positioning System (GPS) hive locations have been recorded, tree species, and the number of hives in each tree.
Some staggering results so far have seen up to 6 hives in one tree, and about 175 hives in 3–4 km of creek line. At another site, 218 hives were recorded in a 1 km stretch of creek line.
There is an urgent need for research into effective methods of eradication and control of feral honey bees in order to develop a strategy that will reclaim the vast number of currently invaded tree hollows. Some apiarists are using queen-excluders on hives to prevent swarming.