Honey bee health
CANR's Delaney has the buzz on UD's new research apiary
9:28 a.m., June 20, 2012--Debbie Delaney has two million new best friends.
That’s the number of honey bees buzzing about in the recently opened University of Delaware research apiary, which joins an existing 30-colony teaching apiary on the university’s Newark Farm.
Peering into cell structures
Delaney, a UD assistant professor of entomology and wildlife ecology, has been researching honey bees for years but continues to be amazed at their abilities, ranging from the way they precisely maintain colony temperature to their figure-eight dances that tell hive mates where to find patches of flowers and water.
She has a hunch that her insect friends have some undisclosed talents, too. For example, in her own backyard beekeeping, she has noticed that hives that swarm and split into separate colonies seem to have fewer mites than hives that don’t split up.
“Varroa mites are the single biggest threat to honey bee health. Most backyard beekeepers and commercial operations treat for mites,” says Delaney. “But I think mites can be reduced naturally by interrupting their brood cycle. Mites require bee brood for reproduction but the brood cycle is interrupted when colonies are split, thus slowing mite reproduction rates. This reduces the total number of mites in each new colony.”
Delaney doesn’t treat with miticides in her personal hives; she simply allows certain colonies in the apiary to swarm and make new colonies when they are so inclined, rather than repress such efforts. Although she relies on gut instinct in her own backyard, Delaney knows she can’t advise other beekeepers until she puts her theories to rigorous test.
That’s where the new research apiary comes in. Delaney received a $50,000 grant from the Environmental Protection Agency for the facility, which is operated in collaboration with a new apiary at Penn State University. Research at both locations will focus on non-chemical ways to manage parasites in small colonies. The goal is to reduce pesticide use by small beekeepers by as much as 80 percent.
Varroa mites are only the size of a small freckle but they can wreak havoc on hives. First reported in the U.S. in 1987, varroa mites are now the major killer of all bee colonies, wild or managed.
“I don’t think splitting and swarming is sufficient to control mites in large, commercial operations but our research project may show that it’s a good management practice for small-scale beekeeping,” says Delaney.
Historically, beekeepers have tried to prevent their bees from swarming because they thought the process was detrimental to honey production and pollination. But existing research already shows that colonies allowed to swarm show lower mite numbers and decreased bee mortality. Delaney’s research may help beekeepers look at apiaries as dynamic systems that require constant turn-over to stay healthy.
“I’m trying to re-define what’s considered to be a healthy apiary,” says Delaney. “We want to reduce the use of chemicals and create sustainable, long-term solutions to the issue of mites and other pests in honey bee colonies.”
Katy Evans is a new UD graduate student who will be overseeing the research apiary. She also will be managing varroa mite research at Penn State’s apiary, with assistance from researchers there. A 2009 graduate of the University of Florida, Evans most recently worked for the state of Florida as an African honey bee lab technician.
A Florida native, she says she is excited to be part of a varroa mite project because the pest is an even greater problem in Florida than here in Delaware. “It’s hotter in Florida, and gets hotter sooner,” says Evans. “This weakens the bees and gives the varroa mites a greater opportunity to infest the hives.”
“I’m really pumped about working in a brand-new apiary and being in charge of the project,” adds Evans. “I hope that our research is able to help small beekeepers better manage their hives.”
UD’s teaching apiary had a good winter and the number of colonies is up. However, this bucks the overall trend of declining honey bee populations. Since 2007, there has been a loss of approximately 33 percent of over-wintered colonies in the U.S. each year.
“Colony declines in domestic honey bees continues to be a major concern,” says Delaney. “We still don’t know the cause or causes. But our research project may give us a better understanding of the role that natural resistance plays in fighting disease or environmental stress, as well as a better understanding of genetic components that contribute to ‘survivor stock.’”
Article by Margo McDonough
Photo by Danielle Quigley