Bee colony deaths in Aotearoa have risen for the seventh consecutive year, with a new report estimating that nearly 14% of the country’s hives were lost in the winter of 2021.
MPI commissioned Manaaki Whenua-Landcare Research to conduct an annual colony loss survey since 2015, to help it monitor losses over time and support work to improve bee health.
The 2021 winter survey, which involved almost half of New Zealand beekeepers, found the overall loss rate was 13.6%, or around 109,800 colonies, up 2.3% from at 2020 levels.
The most frequently reported reasons were suspected Varroa mite infestation and associated complications, followed by problems with queen bees, wasps, and suspected starvation. It was the first time in the history of the survey that varroa was most often attributed to colony losses, with queen problems previously thought to be the primary cause.
MPI lead scientist Richard Hall said most beekeepers have reported that their current Varroa treatments are effective, but lose colonies if they mistime the treatment, underdose or pick. varroa mites following a reinvasion of other colonies.
However, this year’s survey also revealed that not all beekeepers had been treated for Varroa, he said.
Survey prompts educational campaign deployment, new research.
Following the survey results, MPI launched an education campaign in collaboration with the beekeeping industry, to raise awareness on how to control varroa mites and other biosecurity threats.
While the number of commercial beekeepers in New Zealand has declined, the number of small and hobbyist beekeepers has increased. Richard Hall said it was essential that newcomers to the industry had the best information.
MPI has also funded a new research project to better understand how Varroa mite treatments are used in New Zealand and where knowledge gaps may exist. That research will begin later this year, Dr. Hill said.
“This two-pronged work will help them know what biosecurity risks to watch out for and how to manage them.”