Who Is Really to Blame for the Honeybee Deaths?
Imagine you’re a critical worker in a vital global industry. Despite your best efforts, you can’t meet your quota because you keep losing coworkers. What’s more frustrating is that all industry parties blame each other about why you are losing numbers.
Well, that’s what honeybees face these days.
The smallest agricultural worker continues to fight a losing battle. Beekeepers in the U.S. lost 44% of their colonies from April 2015 to April 2016, according to the Bee Informed Partnership, which is supported by the USDA and the National Institute of Food and Agriculture.
That’s 27% higher than the rate beekeepers call acceptable for this insect that’s responsible for one of every three bites of food people take, according to the Pollinator Partnership. Meanwhile, honeybees contribute an estimated $15 billion annually to agricultural production by pollinating crops such as apples and almonds.
“It’s not just the United States or North America,” says Jerry Hayes, honeybee health lead at Monsanto, previously chief of the apiary inspection section for Florida’s Department of Agriculture and Consumer Services. “Everyone is worrying about honeybee health,” he says.
“We have overwintering honeybee colony losses that are way above what’s acceptable,” says Ric Bessin, University of Kentucky Extension specialist, who holds a doctorate in entomology, “Some would say not sustainable. It’s likely due to many stressors.”
Who’s to blame? There’s lots of it to go around. Here are five of the largest causes for the shrinking honeybee workforce.
1. Varroa mite
Agriculture has become a scapegoat for honeybee losses, but it’s not the main threat. The varroa mite is. Particularly disconcerting is that scientists have few remedies for this mite.
The scientific name for this mite is Varroa destructor, which is appropriate considering it can eliminate a hive in 18 to 24 months. The varroa mite is an external parasite that attacks adults and the developing brood. It feeds on the blood of the bee and weakens it and also transmits bacteria and viruses. It’s akin to having a 10-pound weight on your back that sucks out your blood.
“If I could wave a magic wand and get rid of one pest, it would be the varroa mite,” says Reed Johnson, assistant professor in the department of entomology at Ohio State University. Johnson has a doctorate in entomology and almost 20 years of beekeeping experience.
Controlling the varroa mite would increase honeybee health by 70% to 80%, says Hayes.
The varroa mite not only weakens the honeybee by causing physical damage, but it also transmits a host of viruses to the weakened bee. The viruses themselves could wipe out a colony since there’s no treatment for them, says Andy Joseph, state apiarist for Iowa. A beekeeper’s only option is to control the mites, which means using a pesticide.
Like all pests, mites can develop resistance to pesticides, says Johnson.
“No beekeeper wants to apply a pesticide into a beehive,” says Joseph. “But the lower the mite levels, the healthier the bees.”
Beekeepers are trying to get away from harsh miticides and move to smarter varieties of mite control – ones that are natural and relatively gentle on the bees, says Joseph.
“The varroa mite is a formidable pest,” says Johnson. “We don’t have a perfect way to handle them; there aren’t really good solutions for it. Beekeepers are surviving and finding ways to control them, but it’s a constant battle.”
The bad news for you is that the varroa mite doesn’t let you off the hook. Pesticides play a role. Unlike the varroa mite, though, you can form a strategy to control pests while preserving honeybees.
“Even though pesticides aren’t the leading stressor, they are the one we have the greatest control over,” says Bessin.
The following tips can help you mitigate the damage that pesticides can cause.
- Use integrated pest management practices during pesticide applications. Bessin encourages you to consider all options to control pests, including those that aren’t chemical-based. When insecticide applications are necessary, these steps can mitigate damage, says Bessin.
- Choose a pesticide that isn’t lethal to bees when it’s an option. This information is available on the label. “There are some pesticides that are highly toxic to honeybees,” explains Bessin. “The ones that pose the greatest risk will have a honeybee icon in a diamond on the label. There are a small number of active ingredients that are lethal.”
- Read and follow the pesticide label. It provides directions that you must follow. It may identify lethal ingredients, but more common are statements that prohibit application when honeybees are foraging in the treated area.
- Consider timing. Avoid applying pesticides to blooming crops or when other area plants, including weeds, are blooming. “The greatest risk is when plants are in bloom,” says Bessin. “That’s when you increase the potential risk to honeybees.”
- Avoid applying pesticides when bees are foraging during the day. Instead, apply them in the late afternoon once bees have stopped foraging. “Honeybees are generally active about an hour after sunrise until an hour before sunset,” says Johnson.
- Increase communication. Let beekeepers in the area know when pesticide applications will be made so they can manage their hives, Bessin says.
- Watch the weather. If the wind direction is unfavorable, leave a buffer between the application area and the hive.
Using all of these steps together will help reduce honeybee exposure to pesticides, says Bessin.
3. Neonicotinoid insecticide seed treatments
“There’s a lot of finger pointing going on at neonicotinoids,” says Hayes.
The neonicotinoid family of pesticides takes the brunt of the blame for killing bees. They first premiered in corn in the 1990s with Gaucho seed treatment, an imidacloprid insecticide. In the early 2000s, clothianidin (Poncho) and thiamethoxam (Cruiser) hit the market.
Most are water soluble and break down slowly in the environment. This allows plants to take them up in leaves and stems for insect protection during early plant-growth stages.
The good news is all neonicotinoid products aren’t equally toxic to bees, says Bessin. Some uses are much less risky than others, he adds.
“They’re under a review right now with the EPA, and some preliminary reports have been released,” Bessin says.
However, there are four neonicotinoid products that are known to be toxic to bees, says Johnson.
To be clear, pesticides are an issue, says Bessin. “But simply solving the pesticide issue isn’t going to solve the honeybee issue,” he says.
In the meantime, the type of seed lubricant you use to prevent seed from sticking in the planter can help honeybees. Talc and graphite are common seed lubricants, but they don’t reduce dustoff. Bayer has a product called Fluency Agent that reduces the dustoff in treated seeds by 90% vs. talc and 60% vs. graphite in its trials.
“A lot of people want to see it as a black-and-white issue with pesticides,” says Johnson. “Some people want to say that neonicotinoids are always a problem; others say they are never a problem. Neither are true. It’s a big gray area.”
Banning neonicotinoids won’t necessarily help, because the older chemistries that will be used instead can be worse for honeybees, says Jennifer Tsuruda, Clemson University apiculture specialist who earned her doctorate working on honeybee foraging behavior, reproductive physiology, and behavioral genetics.
“Before we push for bans, we have to make sure there are better options,” she says.
Instead, the answer may be in better management.
One option is only using the neonicotinoid seed treatments in fields that have a history of pests instead of preventively, says Johnson.
4. Genetic bottleneck
The bees themselves could be to blame. There’s a lack of genetic diversity in honeybees, because most beekeepers are purchasing queens from a dozen queen breeders, says Joseph. There is the potential that certain traits have been bred down.
Bees have previously been bred for traits like honey production and gentleness, says Tsuruda.
She says it’s akin to finding the perfect mate. Sometimes you can’t find someone who checks off every trait you desire, so, instead, you prioritize. Breeders might have to settle for bees that are able to tolerate the mites but have lower honey production.
Now there’s more attention being focused on breeding, and that may hold part of the answer to combating the varroa mite.
“There are some bees that are more assertive and take care of the mites themselves,” says Tsuruda.
The best option is to breed for a hygienic hive that polices itself. There are a number of different mite-resistant traits that can be selected for, says Joseph. “The varroa mite reproduces in the bee brood,” he says.
A mite will invade a brood cell with bee larva and produce mite offspring that will develop alongside the pupating immature bee. When the mature bee leaves the pupal cells, so do the mites.
“Workers in a hygienic colony will open the pupa cell, and if they find an infestation, they will remove it from the hive,” says Joseph. Another trait being bred will provide bees that aggressively tear mites to shreds.
5. Lack of habitat
Some would say that agriculture is eliminating pollinator habitat and that production ag is to blame.
“Beekeepers wish for more diversity in the habitat,” says Joseph. Ideally, the honeybees would have a food source from early spring to late fall.
Diversity has been taken out of the environment as more and more corn and soybeans are being planted, says Joseph. “It’s a habitat loss for bees,” he says. “Our bees aren’t living in what’s a natural landscape. When corn and soybean prices are high, we see more loss.”
Still, each region differs.
“I don’t see the agricultural areas as a problem,” says Johnson. “As farms get bigger and bigger, there’s less area that can sustain bees. Right now in Ohio, agricultural areas are pretty good.”
Johnson looks to field margins to help support the bees. “Bees produce more honey in agricultural areas than they do in urban and forest areas,” he says.
There are still opportunities for you to help. Cover crops could be part of the solution. “A lot of traits in cover crops are good for bee forage,” says Tsuruda.
Cover crops, field margins, acres enrolled in CRP, and pollinator habitats are all a step in the right direction of providing more plant diversity.
“You have a lot to offer bees,” says Johnson. “Beekeepers and farmers are natural allies in most cases.”
Honeybees need diet diversity. Not all pollens are nutritious, nor are all proteins equal, says Tsuruda.
Without diversity, beekeepers are forced to supplement the diet of bees. “If you want to keep a colony of bees alive in the winter, most years you’re going to have to feed them corn syrup,” says Joseph.
“It’s such a complicated situation,” says Johnson. “These are overlapping problems the bees are experiencing.”
Honeybee challenges are long-term, and continued research will show the best way to help.
Who is Helping?
The EPA has mandated pollinator protection plans. Each state has been asked to develop its own plan, says Ric Bessin, University of Kentucky Extension specialist.
The ag industry also is focused on helping the bees. Following are a few of the current efforts.
Bayer Crop Science has an initiative called Healthy Hives 2020. Launched in 2015, the initiative is looking for tangible solutions to improve the health of honeybee colonies for pest management, hive management, bee genetics, and digital apiculture through the year 2020. Funding was provided for seven projects this past June. Other programs are available through Bayer’s Bee Care Program.
Monsanto is working on gene modification called RNA interference (RNAi), says Monsanto’s Jerry Hayes.
“DNA makes a copy of a specific targeted instruction, and RNA takes it to the cell site to turn a protein on or RNAi turns it off,” says Hayes.
“We’re using what the honeybee would use herself to kill, hurt, or damage the varroa mite,” says Hayes. “We’ve amplified it, put it in sugar syrup, and fed it to the honeybee. When the varroa mite feeds on the honeybee, hopefully it will take up some of this RNAi. The RNAi will impact the varroa mite’s body and make it so the parasite won’t be a negative health impact anymore.”
Monsanto is currently conducting research on the RNAi product at 10 sites with about 2,500 colonies, says Hayes. “By the end of this year, we should have robust data that shows at what level this RNAi product will work.”
BASF has created a research initiative called Living Acres. Its focus is to help farmers and other landowners establish biodiversity on noncropland areas – specifically milkweed plants – to help the monarch butterfly.