More Than Half of N.H. Beehives Didn’t Survive Winter

New Hampshire lost an average of 65 percent of its beehives this winter, according to a survey conducted by the New Hampshire Beekeepers Association, with Merrimack County reporting the highest loss.

The survey, conducted for the first time by the association, covered the period from October 1, 2016 to March 31 and compared how many hives survived through that time period. Data was collected from 261 sites in 130 towns.

The number of hives in the state dropped from 1,004 in October to 350 in April. The number of nucleus colonies (NUCs), small honey bee colonies created from larger colonies, also dropped in that time frame, from 353 NUCs in October to 211 in April, according to the survey.

The one year drop is dramatic because New Hampshire beekeepers already have lost more than 60 percent of their hives from 2009 to 2016, according to the Bee Informed Partnership, which collects national data on the decline of honeybees in the United States.

The state hasn’t seen as big a spike in hive mortality since the 2013-14 winter, when the state lost 52.89 percent of its 537 reported hives. In comparison, last year saw a 29.5 percent loss of its 322 reported hives.

The exact reason why the hives were lost is unknown. Of the 239 responses received on why hives died, almost 45 percent of beekeepers reported they didn’t know what caused their hives to die. The next-highest cause was varroa mites, at almost 30 percent, and starvation at around 17 percent. “Other” reasons included weakness and mice. The survey notes many of the responses listed multiple reasons for hive loss.

One particularly low cause of loss sited was nosema, a widespread fungal disease that is often associated with colony collapse disorder and can cause reduced life spans, difficulty in ingesting food and infertility in queen bees. The disease was attributed to less than 5 percent of hive losses, and a note in the survey questions whether beekeepers know the signs of nosema.

Merrimack County lost 78 percent of its hives — and every single one of its NUCs. Sullivan County lost 62 percent and Grafton County lost 60 percent of its hives.

Survival rates were helped with at least one varroa mite treatment and seasonal feedings, according to the survey. Hives that received multiple treatments for mites were twice as likely to survive as hives that received one treatment.

A similar picture could be seen with whether beekeepers fed their bees in the fall: almost twice as many hives lived that were fed in the fall and winter versus those that were not fed.

Another factor in bee survival was the experience of the beekeeper. Those with over five years of experience saw greater survival rates than those with one to four years of experience.

The full survey can be found at www.nhbeekeepers.org.