Bumble bees were introduced to Tasmania in 1992. The feral populations have spread from sea level to 1450 metres in altitude and have a high level of ecological versatility. In other countries where it has been introduced, it forages on both native and introduced plant species. Because the bumble bee forages on a wide variety of plant species it is likely that it will have an impact, both directly and indirectly, on the Australian environment to some degree.
Other pollen and nectar gathering species include birds, bats, marsupials and a range of native arthropods but this niche overlap for floral resources does not necessarily indicate competition. In Tasmania, a study by Hingston and McQuillan (1999) found that bumble bees competed for a limited pollen resource with two species of native Megachilidae bees causing a displacement of the native bees.
The potential impact of the bumble bee on both native and introduced plants is associated with its flower preferences. The bumble bee is a generalist feeder and has been recorded as feeding on both native and introduced plants, although it is unclear what impact it has on native pollination systems. With respect to introduced species, including declared noxious weeds, its pollination activity can enhance seed set. Thus the potential exists for the conversion of minor “sleeper” weeds into major environmental problems.
Bumble bees cannot be imported to Australia and are prohibited by state legislation from being moved from Tasmania to other states or territories.