Varroa, which kills bee colonies by transmitting viruses from adult honeybees to larvae, was discovered in New Zealand in 2000. It has been in the South Island since 2006.
Bees also face harm from more than 30 pesticides used in New Zealand, a concern expressed by the National Beekeepers Association, which encourages rural contractors to spray safely.
Agrichemical use is controlled by the Hazardous Substances and New Organisms Act 1996 and the Agricultural Chemicals and Veterinary Medicines Act 1997, which make it an offence to use agrichemicals contrary to bee toxicity warnings on labels.
But the dangers of spray are not limited to intensive agricultural practices. Many home garden sprays, including some available at supermarkets, are lethal to bees.
According to Federated Farmers, the bee is one of the hardest workers in horticulture and agriculture; about $3 billion of New Zealand's GDP is directly attributable to the intensive pollination of horticultural and specialty agricultural crops by bees.
New Zealand produces about 10,500 tonnes of honey a year, with exports valued at more than $70 million. In addition, there is a huge indirect contribution through the pollination of clover, used to regenerate nitrogen on farmland, which in turn affects livestock production and sales, including meat exports.
For more information, visit: www.nba.org.nz
