Potential declines in bee populations due to varroa mite infestation could jeopardise Australian horticultural production.
“The Australian Government considers the varroa mite one of the greatest threats to honeybee-pollinated horticulture in the country,” a Rabobank report said.
The threat comes at a time when demand growth for pollination is outpacing growth in beehive numbers.
Report author 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,” he said.
“For example, European honey bees are essential for the almond, mango and macadamia sectors.”
Hive demand in Australia 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 in Australia has remained relatively stagnant,” Stefan said.
“And pollinator needs are forecast to continue to rise significantly due to the expanding horticultural areas in Australia.”
Some growth in the number of hives occurred in the years preceding the 2022 varroa mite outbreak, Stefan said, primarily in recreational beekeeping.
“This slow growth falls short of the projected demand for pollinators in Australia, as we have modelled,” he said.
“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 said a number of scenarios had been modelled to determine the impact of varroa mites on Australian hive numbers, based on insights gained in other countries.
“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 said.