More Bad Buzz For Bees: Record Number Of Honeybee Colonies Died Last Winter

NPR The Salt By Susie Nielsen June 19, 2019

Honeybee hives stand on a field at the Central Maryland Research and Education Center in Beltsville, Maryland. An annual survey of U.S. beekeepers shows the rate of colony death last winter — nearly 40% — was the highest reported since the survey began 13 years ago.  Olivia Falcigno/NPR

Honeybee hives stand on a field at the Central Maryland Research and Education Center in Beltsville, Maryland. An annual survey of U.S. beekeepers shows the rate of colony death last winter — nearly 40% — was the highest reported since the survey began 13 years ago. Olivia Falcigno/NPR

It's a sweltering morning in Beltsville, Md., and I'm face-to-face with bee doom. Mark Dykes, a "Bee Squad coordinator" at the University of Maryland, shakes a Mason jar filled with buzzing honeybees that are coated with powdered sugar. The sugar loosens the grip of tiny Varroa mites, a parasite that plagues bees; as he sifts the powder into a bowl, they poke out like hairy pebbles in snow.

"Right now there [are] three mites per hundred [bees]," says Dennis vanEngelsdorp, associate professor of entomology at the University of Maryland and president of the Bee Informed Partnership, which studies bee survival rates. That's a high rate of mites, vanEngelsdorp says: "If this were September and you were seeing that number, you'd expect the hive to die" during the lean months of winter.

Varroa  mites, tiny pests that can weaken and destroy honeybee colonies, are on display in a small jar.  Olivia Falcigno/NPR

Varroa mites, tiny pests that can weaken and destroy honeybee colonies, are on display in a small jar. Olivia Falcigno/NPR

Bee colony death continues to rise. According to the Bee Informed Partnership's latest survey, released this week, U.S. beekeepers lost nearly 40% of their honeybee colonies last winter — the greatest reported winter hive loss since the partnership started its surveys 13 years ago. The total annual loss was slightly above average.

The survey included responses from nearly 4,700 beekeepers managing almost 320,000 hives, making up about 12% of total managed honey-producing colonies in the United States.

Bee decline has many causes, including decreasing crop diversity, poor beekeeping practices and loss of habitat. Pesticides weaken bees' immune systems and can kill them. Varroa mites (full, ominous species name: Varroa destructor) latch onto honeybees and suck their "fat body" tissue, stunting and weakening them and potentially causing entire colonies to collapse.

Honeybees crawl through a modern-day hive. This past winter saw the most dramatic losses of managed honeybee colonies in 13 years, according to researchers.  Olivia Falcigno/NPR

Honeybees crawl through a modern-day hive. This past winter saw the most dramatic losses of managed honeybee colonies in 13 years, according to researchers. Olivia Falcigno/NPR

"Beekeepers are trying their best to keep [mites] in check, but it's really an arms race," says Nathalie Steinhauer, science coordinator for the Bee Informed Partnership and co-author of the report (vanEngelsdorp is also an author). "That's concerning, because we know arms races don't usually end well."

Steinhauer says Varroa mites are the "number one concern" around wintertime. They've become harder to control, she says, because some of the tools that beekeepers have been using — chemical strips that attract and kill mites, essential oils and organic acids — are losing their efficacy.

Pollinators are responsible for one of every three bites of food we take, according to the U.S. Agriculture Department. Most of these pollinators are domesticated honeybees. They have become essential for many flowering crops, including blueberries, almonds and cherries. Wild insects can't be relied on to pollinate hundreds of acres of these crops, so fruit and nut producers call in commercial honeybee colonies instead.

Beekeepers use this device, called a smoker, to calm honeybees.  Olivia Falcigno/NPR

Beekeepers use this device, called a smoker, to calm honeybees. Olivia Falcigno/NPR

Beekeeping has thus become an essential cog in the machine of American industrial farming. But it's a tough industry. Commercial beekeepers are so migratory that it's difficult to track how many live in each state, and all that moving around is expensive and stressful. Beekeepers have to monitor thousands of hives for sickness and pests.

These winter losses have made business even tougher, says vanEngelsdorp.

"We're not worried about honeybees going extinct. What we're worried about is commercial beekeepers going extinct," he says. When hives die, beekeepers can split healthy hives to replace their numbers — but it's costly to do so. "The question is, how long can they do that and stay economically viable?"

If the beekeeping industry shrinks, he says, crop production will suffer. "If we want to continue to have a food supply that has the variety that we want, we need a movable pollination supply, and those are honeybees," he says. "If we don't have commercial beekeepers managing those, then we won't be able to meet that demand."

Dennis vanEngelsdorp pulls out a frame from a hive. Managed honeybee hives are usually made of stackable, separable components so that beekeepers can closely monitor the colony's health.  Olivia Falcigno/NPR

Dennis vanEngelsdorp pulls out a frame from a hive. Managed honeybee hives are usually made of stackable, separable components so that beekeepers can closely monitor the colony's health. Olivia Falcigno/NPR

Maryann Frazier, a retired senior extension associate for the College of Agricultural Sciences at Pennsylvania State University, who was not involved with the survey, says its results are limited by the fact that they rely on self-reported data from beekeepers. Beekeepers who've lost a lot of bees may be more likely to contribute to the survey, she says.

Still, she says the results are troubling, if unsurprising. Stressed, sick bees in close proximity are likely to die during the winter months. And bees face increasing levels of stress. Until all parties work together to address the sources of that stress, she says, steep winter die-offs will continue.

"I don't expect to see a change in losses over time for this reason. There's been no significant effort to correct what's causing the decline," she says.

Take pesticides, she says. "There's a huge amount of data [and] research showing pesticides are a significant player in the decline of honeybees and other insect species. And yet there's been so little done to make a change on that front," she says. "The EPA has been incredibly ineffective."

She says that pesticide industry leaders often try to shift blame for bee declines solely onto Varroa mites and viruses when in fact, she says, "there is so much evidence that pesticides are a major player in the decline of honeybees."

"And these things are synergistic," she adds. Pesticides can compromise immune systems, so when a mite or other pest hits "a bee compromised by pesticides, it's a downward spiral." Other sources of stress, like changing landscapes, have not been corrected.

Bees crawl over larvae and capped honey cells on a hive frame. Larvae are especially vulnerable to pests like  Varroa  mites.  Olivia Falcigno/NPR

Bees crawl over larvae and capped honey cells on a hive frame. Larvae are especially vulnerable to pests like Varroa mites. Olivia Falcigno/NPR

Honeybees are a "sentinel species," Frazier says, meaning that their losses may warn humans of the larger trend of insect decline worldwide, including the decline of other pollinators like beetles and wild bees. "The picture is well beyond honeybees," she says. "The whole system is crashing."

https://www.npr.org/sections/thesalt/2019/06/19/733761393/more-bad-buzz-for-bees-record-numbers-of-honey-bee-colonies-died-last-winter

[NOTE: The beekeepers in this story are working the bees in short sleeves and without protective clothing. They are located in the state of Maryland. They do not have the danger of Africanized Honey Bees. If you are in areas such as Southern California, which have AHB, we advise that you DO NOT work your bees without protective clothing.]

East African Honeybees Safe from Invasive Pests...for now

Science Daily     Source: Penn State    4/17/14

Several parasites and pathogens that devastate honeybees in Europe, Asia and the United States are spreading across East Africa, but do not appear to be impacting native honeybee populations at this time, according to an international team of researchers.

The invasive pests include including Nosema microsporidia and Varroa mites.

"Our East African honeybees appear to be resilient to these invasive pests, which suggests to us that the chemicals used to control pests in Europe, Asia and the United States currently are not necessary in East Africa," said Elliud Muli, senior lecturer in the Department of Biological Sciences, South Eastern Kenya University, and researcher at the International Centre of Insect Physiology and Ecology, Kenya.

The team first discovered Varroa mites in Kenya in 2009. This new study also provides baseline data for future analyses of possible threats to African honeybee populations.

"Kenyan beekeepers believe that bee populations have been experiencing declines in recent years, but our results suggest that the common causes for colony losses in the United States and Europe -- parasites, pathogens and pesticides -- do not seem to be affecting Kenyan bees, at least not yet...

Read more...

PLOS ONE: Evaluation of the Distribution and Impacts of Parasites, Pathogens, and Pesticides on Honey Bee (Apis mellifera) Populations in East Africa

When Bees Get in Trouble

Bug Squad - Happenings in the Insect World   By Kathy Keatley Garvey    4/4/14

"Bees are incredibly good at picking up what's in their environment."

So said Senior Extension Associate Maryann Frazier of Penn State when she addressed the UC Davis Department of Entomology and Nematology's seminar last Wednesday, April 2 in Briggs Hall.

Frazier, on a trip to California to discuss her research with the Marin County Beekeepers, took time out to travel to the UC Davis campus at the invitation of Master Beekeeper/writer Mea McNeil of the Marin County Beekeepers and associate professor Neal Williams and assistant professor Brian Johnson of the UC Davis Department of Entomology and Nematology.

Frazier, a 25-year extension specialist, expressed concern about the pesticide loads that bees are carrying, as well as the declining population of bees and other pollinators.

Beekeepers, she said, used to be much more concerned about colony collapse disorder (CCD), that mysterious phenomenon characterized by adult honey bees abandoning the hive, leaving the queen bee, brood and food stores behind.  CCD surfaced in the winter of 2006, but today, when beekeepers report their winter losses, "they're not blaming CCD any more," she said. 

Frazier listed the prime suspects of troubled bees as poor nutrition, mites, genetics, stress, pesticides, nosema and viruses. "Varroa mites are a huge issue," Frazier said.

Turning to pesticides, she said a 2007-2010 U.S. analysis of some 1000 samples  (wax, bees and flowers) showed "an astonishing average of six pesticides per sample and up to 31 different pesticides per sample." The analysis, done by U.S. Department of Agriculture's Agricultural Marketing Service Lab (USDA/AMS) screened for 171 pesticides at parts per billion. The samples involved a CCD study, apple orchard study, migratory study and submissions from individual beekeepers.  

Frazier compared the interaction of pesticides in bees to the interaction of medications in humans. When you go to the doctor, you'll be asked the names of the medications you're taking, she said.  The "interaction" situation is similar to what's happening with the honey bees.

In a bee colony, lethal exposures to pesticides are easy to see, Frazier noted. "You'll see dead bees, bees spinning on their backs and bees regurgitating." But the sub-lethal effects can mean "reduced longevity, reduced memory and learning, reduced immune function and poor orientation."

Marin County Beekeepers recently undertook a similar study of pesticide analysis, raising $12,000 to do so ($300 per sample). "Marin is very mindful of pesticides, probably more than any other place," Frazier said. McNeil agreed. The results are pending publication.

"If we truly want to protect our pollinators," Frazier concluded, "three things need to be addressed or changed:

  • Beekeeper reliance on chemicals and drugs to manage mites and diseases
  • Pest control practices, particularly agricultural land
  • The approach of more regulatory agences assessing risk and protecting the environment"

As the seminar participants left Briggs Hall, many could be heard discussing the take-home message: "average of six pesticides per sample, up to 31 pesticides per sample."

Read...

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