A hive of activity

Of the 1500 species of bees living in Australia, we rely on just one to make our honey.

Western honey bees (Apis mellifera) first arrived here in 1822 on the ship Isabella. They took to their new home like wildfire, with large, feral populations established just 10 years after that first arrival. Today, Australia’s agricultural prosperity largely depends on both feral and domestic honey bees.

“It was a deliberate introduction and very successful,” says Professor Ben Oldroyd (BScAgr ’81 PhD (Agriculture) ’86 DSc ’07) from the School of Life and Environmental Sciences who, with Professor Madeleine Beekman, co-founded the University’s Social Insects Lab in 2001. The lab focuses on bees, and examines how we can ensure Australia’s bee population continues to thrive in the face of global threats.

The Western honey bee’s feral population is largely responsible for the pollination of crops such as apples and pears, says Oldroyd. Other agricultural crops rely on Australia’s estimated 500,000 commercial bee colonies, including the rapidly growing almond industry – worth $1 billion in 2015 according to the Australian Nut Industry Council. “It’s because almonds flower in August in Australia, when there are no wild bees about. So almond farmers have to buy or rent bee colonies,” Oldroyd points out.

He thinks the almond industry alone will demand another 100,000 colonies over the next four years; meaning that nearly all of the existing hives in NSW, Victoria and South Australia will need to be involved in almond pollination, or new players must join the industry.

The global bee population has seen a significant drop in the last decade, as colonies collapsed in Europe and the United States. A third of the world’s food comes from crops requiring, or benefiting from, insect pollination, so the crash is reason for concern.

Australia has mercifully been spared from the phenomenon, dubbed Colony Collapse Disorder, but threats to local bees loom large.

The causes of plummeting bee numbers are moot. Beekman says claims that the major bee killer is neonicotinoid pesticides – which are chemically related to nicotine, and more toxic to insects than birds and mammals are exaggerated. In Australia, she adds, bees are more reliant for pollen on native bush such as eucalyptus, so are less exposed to neonicotinoids used in commercial crops.

“The biggest threat to the wild bees all over the world is destruction of habitat. We’re destroying their floral resources, we’re destroying the potential for them to nest, and that really is the biggest issue.”

Of greater concern to Australian beekeepers and horticulturists is the potentially devastating threat posed by the Varroa mite. Varroa is an ecoparasite, but its blood-sucking habits aren’t so much of a problem as the fatal viruses it spreads. In particular, the deformed wing virus has wreaked havoc on honey bees in New Zealand, North America, the Middle East and Europe.

By dint of good fortune and a rigorous biosecurity effort, Varroa is yet to take hold in Australia, so the country’s bee population remains in pretty good shape. But when it arrives (an inevitability, says Beekman) we’ll be in trouble; a field trial conducted by Oldroyd some years ago found that, unlike some international populations, Australia’s honey bees have no resistance to Varroa.

What should we do when Varroa comes to town? The best ecological solution would be to do nothing and allow our bees to gradually develop an immunity to the mite and its virus, say Oldroyd and Beekman. But this solution would destroy bee-reliant food crops and honey producers.

Beekman spends a lot of time studying Varroa in South Africa, where the mite hasn’t infected local bees with the virus. There (and in South America), Varroa is prevalent but the virus has not occurred. Elsewhere, there are populations that have developed resistance to the virus.

“We also know of populations that carry the mite and the virus and the bees are quite happy,” says Beekman.

Such a result takes time though. “If your livelihood depends on having bees, you’re not going to be happy with this suggestion because it means, for a few years, you won’t have enough bees.”

One answer could be vaccinations. Work by Dr Emily Remnant, from the Social Insect Lab, to immunise bees against the virus, won her top honours at this year’s Science and Innovation Awards for Young People in Agriculture. Developing pesticides targeting the mite is another solution, as is importing Varroa-resistant honey bees from the United States.

Unfortunately, many honey bees in the US are the notoriously dangerous ‘Africanised’ honey bees, which are European bees crossed with an African bee strain. The aim was to produce a bee that produced honey more easily in tropical climates, but the resultant bees are also much more aggressive. Obviously, Australian beekeepers don’t want a bar of them.

Dr Nadine Chapman (BA ’05 BSc (Hons) ’05 PhD ’10), also in the Social Insects Lab, has developed a genetic test to prevent these bees from entering the country.

For now, our honey bees thrive, but it’s not something we can take for granted. Oldroyd and colleague Dr Tanya Latty’s research includes investigating the density of wild honey bees across Australia’s cropping areas.

“We put up a helium balloon with a pheromone lure that smells exactly like the queen bee and we suspend it in the air,” says Oldroyd. “The males find it irresistible and go into traps that are also suspended beneath the balloon. We can get several hundred drones in a few minutes.”

Oldroyd and Latty use this technique to estimate how many colonies live in the surrounding area and whether they are sufficient to pollinate local crops. Oldroyd lets his third-year students conduct similar pheromone-trapping experiments on Oval No. 1 at the University. “They love it,” he says.

Across the board, Oldroyd says there is a growing interest in urban beekeeping. He was heartened to see a lot of young hipsters “getting into bees” at a recent NSW Beekeepers’ Association Conference. “They’ll probably have to shave their beards off pretty quickly because bees get stuck in them. But it’s all good.”

As beekeeping becomes an urban pastime, the long-term health and economic viability of the wider Australian bee population is being enhanced by the work of University researchers.

Find out more about the University’s Social Insects Lab.

Written by Jocelyn Prasad
Photography by Stefanie Zingsheim and Ben Oldroyd