Bee deaths on the rise
HONEY: Varroa mites are the leading cause of hive losses, reports
Bee colony deaths in Aotearoa have risen for the seventh year in a row, with a new reporting estimating nearly 14 per cent of the country's beehives were lost over the 2021 winter.
The Ministry for Primary Industries has commissioned Manaaki Whenua-Landcare Research to conduct a colony loss survey annually since 2015, to help it monitor losses over time and support work to improve bee health.
The 2021 winter survey, which involved nearly half of New Zealand's beekeepers, found the overall loss rate to be 13.6 per cent, or about 109,800 colonies, up 2.3 per cent on 2020 levels.
The most commonly reported reasons were suspected varroa mite infestation and related complications, followed by problems with queen bees, wasp and suspected starvation.
This was the first time in the survey's history the varroa mite had been most frequently attributed to colony losses, with queen problems previously being considered the leading cause.
MPI senior scientist Dr Richard Hall said most beekeepers reported their varroa treatments were effective, but that they lost colonies if they got the timing of the treatment wrong, under-dosed, or picked up varroa from reinvasion from other colonies.
However this year's survey also found not all beekeepers had treated for varroa, he said.
Survey prompts roll out of educational campaign, new research
As a result of the survey findings, MPI had begun a collaborative education campaign with the beekeeping industry, to raise awareness on how to tackle varroa mites and other biosecurity threats. While commercial beekeeper numbers were dropping, the number of small beekeeping operations and hobbyists has grown. Hall said it was essential those new to the industry were equipped with the best information.
MPI had also funded a new research project to better understand how varroa treatments are used in New Zealand and where gaps in knowledge may be. This research would begin later this year, Hall said.