The demand is high for more horticultural crop production but varroa mite infestations are causing grief for many growers
Potential declines in bee populations due to varroa mite infestation could jeopardise horticultural production, according to a newly-released report.
The agribusiness banking specialist Rabobank is behind the report, explains how the parasitic varroa mite, that attacks European honey bees, was detected in Australia in 2022 in New South Wales and has since been deemed ineradicable.
“The Australian government considers the varroa mite one of the greatest threats to honeybee-pollinated horticulture in the country,” the report outlines.
In the report, How varroa mites might impact pollinators, the bank’s RaboResearch division says this threat comes at a time when demand growth for pollination is outpacing growth in beehive numbers.
Report author, RaboResearch general manager Australia and New Zealand Stefan Vogel said many horticultural crops depend on pollinators.
“While not all require European honey bees, several key industries already face high demand for these pollinators, and this demand is expected to increase. For example, European honey bees are essential for the almond, mango and macadamia sectors,” Stefan Vogel explains.
Hive demand has tripled since 1990 to meet the strong growth in horticulture pollinator needs, especially for pollinating tree nuts, the report says. However, the number of commercially managed hives has barely grown.
“Over the past three decades, the number of hives has remained relatively stagnant,” Stefan Vogel adds. “And pollinator needs are forecast to continue to rise significantly due to the expanding horticultural areas.”
Some growth in the number of hives occurred in the years preceding the 2022 varroa mite outbreak, Stefan Vogel adds, primarily in recreational beekeeping.
“This slow growth falls short of the projected demand for pollinators in Australia, as we have modelled. We project a substantial increase in demand due to the expansion of commercial crop acreage requiring pollinators, particularly for tree crops such as almonds.”
Stefan Vogel said the bank had modelled several scenarios to determine the impact of varroa mites on hive numbers, based on insights gained in other countries.
“These insights show that after a varroa mite outbreak in other countries like New Zealand and Canada, the hive numbers typically experience a significant decline in the first five years, followed by a recovery usually starting after six or more years,” he adds.
The RaboResearch report for Australia indicates if the situation mirrors the Canadian and New Zealand scenarios, it will mean an approximate 8% decline in hive numbers within four to five years.
The pollination needs for 2025 would still be met. However, if they followed the US scenario, a 25% decline in hive numbers within seven years, they would not.
Stefan Vogel said all scenarios indicate a local pollinator supply shortfall within three to five years due to the combined effects of the modelled varroa mite hive reduction and the strong growth of horticulture acreage.
“The trend is clear,” Stefan Vogel continues, “the growth in the number of beehives has not kept pace with the increasing demand for pollinators”.
“The small margin between the number of available pollinators and the calculated minimum required for effective pollination means local horticulture crops that rely on bees for pollination are vulnerable.
Beekeeping challenges
Stefan Vogel also highlighted how tight beekeeper margins might pose future pollinator challenges.
“Increased beekeeping costs, due to varroa mite measures and inflated inputs like energy and labour costs, combined with continued pressure on honey prices from heavy import competition, could potentially drive-up pollination service fees to counter a heavy reduction in hive numbers,” he adds.
Prices for Australian-produced honey have been declining for years, nearing the levels of imported honey, the report highlights.
“Nearly 20% of Australia’s honey supply comes from imports, 45% from small local producers and recreational beekeepers and 36% from large local producers,” Stefan Vogel explains. “In recent years, imports have increased, particularly low-priced products from China, Malaysia and Thailand.”
Stefan Vogel also explained how income from honey, wax, and pollination services is crucial for beekeepers. “However, beekeeping margins have been pressured by rising costs and declining honey prices.
“The additional expenses associated with managing the varroa mite further strain these margins and will likely lead to increased fees for pollination services,” Stefan Vogel added.
Pollination strategies
There is a growing focus on the use of proactive pollination strategies, even among sectors that have traditionally relied on native bees and passive pollination, Stefan Vogel adds. “The expected scarcity of pollinators underscores the need for effective pollination strategies.
The Rabobank report notes several key measures that could help prevent a future pollinator shortfall – increasing beehive numbers, facilitating bee movement, adopting alternative pollinator strategies and improving biodiversity.
“Firstly, hive numbers for each commercial beekeeper need to grow significantly, along with improved management of pollinators by horticulture businesses,” Stefan Vogel emphasises.
“Moving bees across state borders is also key, especially during the peak pollination period from July to October, to ensure a substantial inflow of hives into Victoria’s horticulture sector.
“And beekeepers and the horticulture sector also need to look at adopting alternative pollinator strategies, such as using technologies like drones or robotics, breeding self-pollinating crops, using and attracting more native pollinators and having horticultural companies manage their own pollinators.”
Mr Vogel said while the varroa mite presents a formidable challenge, proactive measures and innovative strategies can help safeguard Australia’s pollination needs. “Collaboration between beekeepers, horticultural businesses, and policymakers will be essential to navigate this crisis and secure the future of local pollination services,” he concluded.
