A long-term goal is to breed bees with a higher resistance to the varroa mite. While that is an ideal solution, there is
much that can be done in the meantime, scientist Mark Goodwin, of the HortResearch apiculture team, says.
HortResearch is working on a number of projects aimed at developing an Integrated Pest Management programme suitable for
controlling varroa under New Zealand conditions.
One element involves registering organic control products for varroa. Many New Zealand beekeepers prefer not to use
synthetic chemicals in their hives, so HortResearch and the Ministry of Agriculture and Fisheries (MAF) have applied for
registration of formic acid, oxalic acid, and thymol. These simple compounds are cheap and effective, and can be used
alternately with the pyrethroids to stop bee mites from developing a resistance to an over-used single product. Organic
beekeepers will use them for varroa control exclusively, and this will require higher skill levels than those needed for
the use of synthetic compounds.
Other research projects underway include looking at how fast mites reproduce in colonies, when numbers within a hive
reach levels where treatment should begin, the best methods of sampling hives to establish exactly what’s going on, and
what control strategies work best.
In addition to funding research, MAF is funding an education programme to teach beekeepers how to control varroa. This
has also enabled scientists to develop and present a series of educational workshops around the country in conjunction
with AgriQuality. The workshops are based around a handbook on varroa management written by HortResearch scientists,
which has been mailed to every New Zealand beekeeper. Three videos on different aspects of varroa management are also
being developed. Updates in the industry journal NZ Beekeeper complete the process of making sure everyone is able to
work constructively on minimising the problems caused by the arrival of the mite.
Varroa may result in many of our 4,000 beekeeping hobbyists ceasing to keep bees. The increased cost may also make some
commercial beekeeping enterprises unprofitable. There will likely also be increased costs to growers hiring hives for
pollination. As honeybees will not be able to survive in NZ without human intervention most feral hives will die out, Dr
Goodwin said, in turn meaning that more people will need to hire hives to ensure their crops are adequately pollinated.
Controlling varroa now adds at least $14 per hive per year for materials to treat hives, in addition to increased labour
costs for beekeepers. But export markets for honey and bee products shouldn’t suffer much as the varroa bee mite is,
after all, found in almost every country where there are bees. And as research continues there will be more good news