The European honeybee has been in Australia for almost 200 years and its presence is often seen as benign, even beneficial. But that may not always be the case.
Feral populations of European honeybee may disrupt natural pollination processes by outcompeting native pollinators, such as the stingless bee, in ecosystems where floral resources are scarce.
But the full effect of the invasive bee species and its interactions with native biota is not fully understood by scientists.
"It really depends on what resources they are sharing and whether any of those resources are in short supply," University of New England professor Caroline Gross said.
As biodiversity and natural resources dwindle from climate change, Dr Gross said the importance of further research and understanding was increasing.
Aggressive bees
A traditional owner at a Top End station believed he was seeing the effects firsthand and is on a mission to raise awareness.
Garawa man Frank Shadforth owns Seven Emu Station in the Gulf of Carpentaria, 1,000 kilometres south-east of Darwin, and grew up foraging for food in the bush.
He said the health of his country had changed for the worst in the past few decades.
Mr Shadforth blamed feral honeybees for a decline of native stingless bees and irregular pollination of the native trees on his property.
"It takes too much off the trees, it's a very aggressive bee, and I've seen them attack the native bee to take the honey," Mr Shadforth said.
"[Pollination] is there but it's not as good as it should be."
Mr Shadforth said numbers of some native bird species and flying fox had also dwindled because of the poor health of the bush.
He hoped his anecdotal account would prompt more action and more interest from scientists and society at large.
"I feel very sad and upset, because I have grandchildren," he said.
"Take this very seriously because it's a problem for everyone, and the quicker we get out there [to fix it] the better."
More research needed
Dr Gross has researched the impacts of introduced honeybees on plant fitness and native bee behaviour since 1986, although the science is not settled on the effects of native and introduced bee species co-foraging.
She said the evidence was not clear cut and had much to do with individual ecosystems and whether the resources shared by native and introduced bees were in short supply.
"In some systems it has been shown that honeybees can impact upon the native bees by being aggressive at the floral interface," she said.
"We found this in North Queensland on a little shrub called Melastoma, and there what we found is that the honeybees would be quite aggressive and almost sumo wrestle native bees from the flowers."
Dr Gross said more research was needed on the effect that honeybee aggression had on the fitness of native bee populations.
Her team's research had also found feral honeybees competed for resources with native honey-eating birds, and were often poor pollinators of native plants.
"There can be a variety of ways honeybees can impact on the fruit set and seed set of native plants," Dr Gross said.
University of Sydney bee biologist Michael Holmes said the European honeybee was an effective invasive species because it was a "generalist" that was not picky about where it nested or what flowers it visited.
"A lot of people forget that [honeybees] are introduced in Australia, and people didn't really think of what effect they might be having on native flora and fauna," Dr Holmes said.
"Stingless bees do use similar kinds of nest sites [to honeybees], so whenever there's an introduced species that uses the same resources as native species there's potential for competition."
The Federal Department of Agriculture, Water and the Environment noted feral European honeybees may outcompete native fauna for floral resources and displace endemic wildlife from tree hollows.
However, there was "insufficient research" to fully describe their impact.
