Bee Killer Still at Large; New Evidence Makes Pesticides a Prime Suspect

By Smriti Rao | March 26, 2010 1:54 pm

beeThis spring, many beekeepers across America opened their hives and found ruin within. At a time when they should have been buzzing with activity, the hives were half-empty, with most adult bees having flown off to die. A new federal survey indicates that 2010 has been the worst year so far for bee deaths. Another study suggests that pesticides might be to blame for the mass wipeout of adult honeybees.

This winter’s die-off was the continuation of a four-year trend. At any given point, beekeepers can expect to see 15 to 20 percent of their bees wiped out due to natural causes or harsh weather. But this alarming phenomenon, termed colony collapse disorder (CCD), has seen millions of bees perish in a mysterious epidemic, with some farmers losing 30 to 90 percent of their hives.

As for the cause of this epidemic, experts say their best guess is that many factors are combining to sicken bees, with the list of culprits including parasites, viruses, bacteria, poor nutrition, and pesticides. Now a new study published in the scientific journal PLoS ONE strengthens the case for pesticides’ culpability.

In the study, researchers found about three out of five pollen and wax samples from 23 states had at least one systemic pesticide — a chemical designed to spread throughout all parts of a plant [AP]. The scientists say that in the 887 wax, pollen, bee, and hive samples, they found 121 different types of pesticides. The pesticides weren’t present in sufficient quantities to kill the bees, they say, but when combined with the other detrimental factors the mix could prove lethal for the tiny workers.

This is the fourth year of honey bee losses across the United States. In 2007, the nation’s beekeepers lost 32 percent of their colonies. In 2008 they lost 36 percent. In 2009, 29 percent [Discovery News]. With the official 2010 numbers (which will be announced in April) expected to be even worse, farmers across the United States are worried. About one-third of the human diet is from plants that require pollination from honeybees, which means everything from apples to zucchini [AP]. Almond growers in California are particularly concerned; the state is one of the largest producers of almonds in the world, and with the decline in the bee population, pollinating the trees has been a challenge. CCD has also dealt a tough economic blow to the beekeepers who truck their hives to the orchards. For Zac Browning, one of the country’s largest commercial beekeepers, the latest woes have led to a $1 million loss this year [AP].

As federal, state, and private agencies hunt for the elusive bee killer, the USDA has advised people not to use pesticides indiscriminately—especially at midday when honey bees are most likely out foraging for nectar. The agency is also asking people to plant and encourage the planting of good nectar sources like red clover, foxglove, bee balm, and joe-pye weed to give the besieged honey bees a boost.

Related Content:
80beats: Honeybee Murder Mystery: “We Found the Bullet Hole,” Not the “Smoking Gun”
80beats: Are Reports of a Global Honeybee Crisis Overblown?
80beats: Honeybee Killer Still at Large
DISCOVER: The Baffling Bee Die-Off Continues
DISCOVER: Beepocalypse

Image: Flickr / Todd Huffman

CATEGORIZED UNDER: Environment, Living World
  • YouRang

    No one has suggested failed homing mechanism. I believe bees use a combination of sun and magnetic signals to navigate. The direction of true north magnetic field in America changes more rapidly than in Australia (which hasn’t had collapse syndrome). Also the effect of CO2 induced climate change has lately been to make America cloudier so the navigation sense is also damaged.

  • nick

    Bees see in ultraviolet. Clouds do not block UV rays.

    And ‘CO2 induced climate change” affects the whole world, not just the USA.

    Also, you said “you believe.” Scientific evidence?

    The minor movements of true magnetic north are still so many thousands of miles away from us here in North America that it’s not gonna matter. And the magnet field has ALWAYS wandered.

    Lets face it, pesticides are, by design and by name, meant to kill insects. Systemic pesticides go in through plant roots usually (or the stomata on the leaves if it’s a spray-on systemic) and become part of the whole plant. They are illegal (I hope; at the very least it is contravened on the labelling) to use on human food crops due to the fact that pesticides are toxic to us as well, and if they’re part of the plant they’re part of the fruit. Don’t believe me ? Go read the label. It’ll tell you to suit up like an astronaut before using, don’t get it on exposed flesh, if you do rinse for 15 minutes with water, call poison control, etc.

    A more sensible way of dealing with crop pests is the introduction and management of predator insects. Also expensive. The way we will probably end up dealing with this is through GMO crops – made by the same people that make these pesticides. “Oh, don’t worry about the bees, we’ve invented apples and almonds and etc. that just pollinate themselves! No more pesticides needed either, because we bred natural pesticides into the plants too! And natural herbicides so they nuke any foreign plant near them. SAFE!!!!”

  • m


    CO2 makes the sky cloudier?? thanks for that…i needed a good laugh.

    uh…FYI – clouds are mostly made up of water.

    and i love the idea of introducing a “predator insect”. yup…good idea. we learned nothing from the Killer Bees. Let’s do it again!

  • Della Rey

    This is so sad….. Bees need help! Maybe that’s why the Mayan Calendar ends in 2012!

  • Erin

    What needs to happen is a nation wide, actually world wide crop mob planting. Let’s seed the interstate median strips, let’s sow joe-pye weed and red clover in the abandoned fields and lots in Detroit. Let’s start growing some pesticide free herbaceous vegetation and let the bees keep doing their thing. Nuff’ said.

  • JD

    Why are so may Apiaries planted beside highways? If they knew how many thousands of bees are killed by vehicles each day that would solve half of this problem.

  • Lea

    Likely it is a combination of many factors.
    Climate/Environmental changes, pesticides, pollen from GM crops, disease (too many in not enough space), that stuff they spray from airplanes, etc.
    Mayhaps humans may have to become nature fairies if they disappear completely.


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