Killer corn?

Ontario beekeepers lose millions of bees and Health Canada suspects corn seed insecticide

Ontario’s frustrated beekeepers have lost millions of honey bees this year and are pointing the finger at what they say is the culprit: sprayed pesticides that coat most corn and soybean seeds.

Said Davis Bryans, a fourth generation beekeeper and owner of Munro Honey and Munro’s Meadery in Alvinston: "We have about 3,000 hives. About a third of them were hit this year. We lost between 30 per cent and 40 per cent of the bees in the hive."

He said the bees were healthy in the morning when they began gathering pollen on plants and the "only thing happening at this time of year was that corn was being planted. The bees came back loaded with pollen, and the other bees wouldn’t let them in."

One hive can have up to 40,000 bees in the spring and up to 100,000 bees in the summer. Munro said 900 of his 3,000 hives were affected. He lost 13.5 million bees.

Zurich-area beekeeper Bill Ferguson said that within an hour of corn planting near his apiary, his bees started dying. The federal government tested dead bees gathered from the apiaries owned by Ferguson and Bryans, among others, and found 27 of 38 samples were contaminated with the same insecticide that coated the corn seed.

While no conclusive evidence exists for what is causing a perennial death of bees, the charge against most corn going into the ground is now being taken more seriously in Ottawa, as Bryans’ comments were not off-the-cuff. They were made to 11 MPs on the federal agriculture committee last month.

The meeting provoked NDP MP from British Columbia, Alex Atamanenko, to remark: "I’ve been on this committee for over six years now and I haven’t really heard many more gut-wrenching stories than what you folks are saying today. Clearly this is serious. This is a crisis situation."

Atamanenko added: "We need some kind of a stop or a moratorium until we can independently assess what’s going on here. Obviously there appears to be a correlation between the planting of corn and the dead bees."

Within days of the committee meeting, Bryans received a Health Canada letter telling him that a "re-evaluation" of neonicotinoids, the insecticide in question, is underway. Stated Health Canada: "There continues to be emerging science on neonicotinoids and their potential effects on pollinators."

The issue is bigger than that. The Health Canada letter arrived about one month after Bryans received a phone call from American scientist Tom Steeger, a senior science advisor with the U.S. Environmental Protection Agency, who peppered Bryans with questions in search of common clues as to why dead bees are showing up throughout the United States, where record-busting acres of corn are being grown.

The problem of dying bees is so severe that after tremendous losses in 2007, we got the name colony collapse disorder. So, is corn the cause?

Scientists at Purdue University in Indiana reported in an online seminar this year that colony collapse is a world wide problem with multiple causes. Three recently published studies in Science magazine concluded that exposure to certain insecticides causes mortality and hive abandonment. As recently as last month a British study argued that the miniscule Varroa mite, based on its impact in Hawaii, is a prime suspect by spreading a virus in bees.

Most agricultural "researchers would agree that parasitic mites are the principal cause of colony death," said Purdue honey bee specialist Dr. Greg Hunt. "But there are other factors, other diseases and insecticides."

Hunt received numerous calls from farmers in the spring, saying that bees were dying in front of their hives while neighbours were planting corn. While people need not worry about minute levels of neonicotinoids in corn and honey, some insecticides can be scraped off corn and become airborne during planting and land on nearby dandelions, Hunt said. "We estimate that a single Poncho corn kernel contains enough active ingredients to kill easily tens of thousands of bees. Perhaps 100,000 or more."

Purdue University field crop entomologist, Dr. Christian Krupke, argued that "sub-lethal rates (of neonicotinoids) are a lot more important than what we thought all along and sub-lethal rates are what most honey bees are exposed to."

The big questions now are more long term, he said. "Do we really need these seed treatments on every corn seed in North America? There is really not a lot of data suggesting we do need it on every corn seed. Do we need all our crop treated with these insecticides that last all season long? These are questions that should be asked."

The Purdue scientists recommended that beehives be moved away from agricultural fields as bees will forage up to five kilometres from hives. But "it’s not as simple as saying wherever treated crops are planted the bees die," Krupke explained. "There are some areas where neonicotinoids-treated crops are planted and the bees don’t seem to have this (colony collapse) effect."