... and the problems they face. U of D researchers test hive monitoring tech.

According to the American Beekeeping Federation, about one third of the food we eat relies on honey bee pollination.

“A lot of our food would disappear or at least be scarce and expensive without honey bees,” said Dan Borkoski, an apiary research associate at the University of Delaware. “Fruits, nuts, even meat, because bees pollinate feed for livestock.”

In Delaware, honey bees pollinate our strawberries, blueberries, cucumbers, pumpkins and watermelons, and certain groups are taking steps to safeguard them.

There are about 400 different bee species in the state, and they are all pollinators. However, honey bees are different because they have been domesticated for both honey production and beekeeper-managed crop pollination. The population of wild honey bees worldwide is impossible to count, so most modern data on honey bees comes from these managed populations.

Farmers rent beekeepers’ services, and since there are very few wild honey bees left, those services are in high demand.

“So many crops in Delaware depend on honey bee pollination,” said State Apiarist Meghan McConnell. “We really depend on beekeepers to be interested in this, to maintain colonies of managed pollinators.”

According to a new study published in Biological Conservation, honey bee populations worldwide have been on the decline for decades. In 1947, U.S. scientists recorded six million honey bee colonies. The population has been declining ever since, at an almost 1 percent rate annually, for a variety of reasons.

But Delawareans needn’t worry – at least not yet. There are about 300 registered beekeepers in Delaware and about 6,000 managed hives.

Varroa mite

“Honey bees face a lot of different stressors: pathogens, parasites, monoculture, of course pesticide use, more urban environment and less habitat,” McConnell said. “All these coming together, you don’t see as many … wild or feral populations because they need more help to survive.”

Experts, including Dan Borkoski, say the biggest threat to honey bees is a parasite, the Varroa mite.

“It’s kind of like a tick on bee, but it would be the size of a hamburger on a human. A bee might have four or five of them,” he said.

Varroa mites feed on the blood of adult bees and spread diseases between hives. Varroa mites cause the most damage to bee larvae and pupae, according to the United States Department of Agriculture. Bee larvae and pupae infested with Varroa mites become adult bees with diminished vitality, or worse, suffer deformities or die before they’re fully developed.

Borkoski is constantly doing mite counts in his hives. If he reaches a certain threshold, he may use a miticide, but generally, he tries to avoid it. Miticides, or mite-killing chemicals, can be harmful to bees and the pesky Varroa mite has developed resistance to some.

“Honey bees are resilient and adaptive, but they haven’t been able to adapt to the Varroa mite yet,” Borkoski said.


Pesticides keep crop-destroying bugs away, but they can also have a negative effect on beneficial bugs, like bees.

According to numerous peer-reviewed studies, neonicotinoid pesticides are particularly harmful. Neonicotinoids are a relatively new and widely used class of pesticides that are chemically similar to nicotine. The European Union banned them from outdoor use in 2018, and some states restrict their use, including Maryland.

However, according to Chris Wade, program administrator for the pesticides section of the ag department, neonicotinoids aren’t causing any noticeable problems in Delaware.

“We haven’t had any major incidents,” he said. “We do our best to communicate to growers and applicators to follow the pesticide labels … and the [best management practices] in the Pollinator Protection Plan give applicators guidance on ways to avoid harming bees during applications. I would like to think this is part of the reason.”

The Managed Pollinator Protection Program details the ways farmers can mostly safely use pesticides. Wade’s department regulates the over 14,000 registered pesticides in Delaware and investigates when a large number of bee deaths are reported.

“We honestly don’t get a lot of bee kill calls,” Wade said. “I’ve been here 15 years and we might get one or two a year, if any.”

Herbicides and fungicides can also be harmful to bees.

Glyphosphate, more commonly known as Roundup, is a popular herbicide used to rid lawns of weeds. A 2018 University of Texas study found that it harms bees, but its manufacturer, Bayer (formerly Monsanto) says the study wasn’t big enough to be reliable.

Regardless of the effects, Borkoski encourages people to stop using herbicides.

“Allow things to bloom. I love a yard full of dandelions, it’s a lot prettier than grass,” he said.

Things commonly considered weeds, like dandelions, milkweed and purple deadnettle, are bee feed. Leaving them to grow means bees will have a nutritious variety of food.

Urbanization and climate change

Sprawl and urbanization have greatly limited bees’ food choices.

“With development, there are fewer areas with things blooming, so there’s less for bees to forage and it’s harder for them to find good nutrition,” Borkoski said.

Urban and suburban development causes habitat loss, as does climate change. Suitable environments for bees are becoming smaller, or changing too quickly for them to adapt.

Bees also suffer indirectly from the havoc climate change wreaks with the seasons. One the biggest effects is on the growth cycle of plants.

Bees collect pollen on the many tiny hairs on their bodies as they feed on the nectar of plants, so pollination and feeding happen simultaneously. The synchronicity of bees’ pollination/feeding schedules and the blooming of flowers is important. Studies have shown that a mismatch of a few days can have detrimental effects on bees.

When flowers bloom before bees are ready to pollinate, nectar becomes limited and competition more intense when they are ready. When flowers bloom after bees are ready to pollinate, they suffer poor nutrition or die.

Residents can do their part to counteract urbanization and climate change in their own yard.

“Plant a large variety of flowers, especially ones that grow in early spring or in fall,” McConnell recommended. “That’s what we consider the dearth, when there’s not a lot flowering and bees are really hungry. Dandelions, clover, don’t spray weeds that come up.”

Bee-neficial ideas

In the face of so many stressors, bees need human help. Some innovative technology is allowing beekeepers to monitor their hives remotely.

Borkoski’s job, generally, is to maintain the University of Delaware’s honey bee hives on campus in Newark and elsewhere, including Redden State Forest in Georgetown. That means making the three-hour round-trip drive up and down the state and disturbing the hives.

“I’ve learned over the years one of the best things you can do is not disturb them,” Borkoski said.

An application called ApisProtect, which uses sensors to detect conditions inside the hive and transmits the data back to the beekeeper, may help. The University of Delaware is testing the Irish technology.

Each hive at Redden is equipped with an ApisMonitor, a small device powered by a solar panel outside. It monitors temperature, humidity, carbon dioxide, sound frequencies and physical movement.

“If a hive tipped or blew over we would be alerted,” Borkoski said. “Their readings could indicate or even predict big events within the hive, so it would help me decide whether or not to make that drive. It would help save on labor.”

The agriculture department is helping the bees by further educating beekeepers and specialty crop growers through a three-year, $50,000 USDA grant called “Increasing the Sustainability of Beekeeping in Delaware through Education and Teaching Apiaries.”

Specialty crops are defined by the USDA as fruits, vegetables, tree nuts, dried fruits, horticulture and nursery crops – all of which are pollinated.

Through the grant, best management practices for beekeepers will be explained and demonstrated in workshops, trainings and hands-on sessions in a network of teaching apiaries.

“Our target is to have at least one in each county,” McConnell said. “These education opportunities will improve the knowledge, skills and abilities beekeepers need to operate their apiaries in a sustainable manner and minimize colony losses. This will, in turn, benefit specialty crops with healthier pollinators.”

The timeline for the workshops, trainings, etc. is still in development. For more information about beekeeping, visit agriculture.delaware.gov.