Just two years ago, Dave Schuit’s honeybee hives were thriving and he was planning an expansion of the family business. But in the last year, an astounding 37 million of his bees in 600 hives have died and he doesn’t know if he’ll have any honey harvest at all this year.

Now, he’s joining a growing number of beekeepers across the country pointing the finger of blame at a group of pesticides they say needs to be banned.

For Schuit, last summer’s bee season started out well.

“And then when they started planting corn, my bees started dying by the millions,” Schuit told CTV’s Canada AM Friday.

“When they came out of their hives, they formed a blanket (on the ground.) They became paralyzed, their legs couldn’t move, their wings couldn’t move, their tongues were sticking out and the venom was dripping from their backside.”

For Schuit, watching the insects he had long-cared for die in front of him was as hard as it would be for a cattle farmer to watch cows in their death throes.

“It was terrible agony. It was terrible to see my bees dying,” an emotional Schuit said.

Nearly half of Schuit’s operation is now gone, and while some of his bees are surviving, his queens are not faring well. He was once able to keep a queen alive in a hive for several years, but now Schuit says “I can’t keep a queen alive one year.”

For several years, beekeepers across Canada and around the world have been trying to sound the alarm about an ongoing die-off of their insects.

In 2012, more than 200 bee farms in southern Ontario and Quebec reported an "unusually high number" of losses, according to a recent Health Canada report.

The beekeepers point out that the loss of their bees is not just destroying their livelihood; it’s also threatening all sorts of crops that rely on bees for reproduction and to transfer pollen and seeds from one flower to another.

Scientists have been baffled by the die-off, noting that global warming has brought several changes to the ecosystem that could be behind the deaths. But now, many farmers have grown convinced that the greatest culprit is a relatively new class of pesticides. They’re called neonicotinoids, and as their name suggests, they derive from nicotine.

Honeybee researcher Clement Kent, from York University’s Department of Biology, says farmers first started using neonicotinoids about 20 years ago and their use has grown ever since.

“These have been some of the bestsellers in the pesticide market for the last 10 years, and they’re used on all kinds of crops,” he told Canada AM.

Kent explained that neonicotinoids aren’t sprayed onto plants, but are rather applied to the corn seed before it is sown. The chemical then finds its way into the plant’s leaves but also into its pollen where it’s ingested by bees when they collect pollen for honey.

Kent says the chemicals use the power of nicotine to kill off pests.

“Nicotine protects plants from bugs because it’s actually a nerve poison that acts more strongly on bugs than on people, which is why we can smoke a cigarette and not drop dead,” he said.

Last year, Health Canada’s Pest Management Regulatory Agency took samples from dead bees in Ontario and Quebec and found clothianidin, a type of neonicotinoid, in 70 per cent of the Ontario samples.

The agency is currently re-evaluating the status of three pesticides in the neonicotinoid class to determine if they pose an environmental risk to bees. But Schuit and many other beekeepers want to see a complete ban now.

They note that the European Union decided in May to impose a temporary two-year moratorium on the pesticides, to monitor how it affects the quickly-declining bee populations there.

Schuit says he spoke before the Standing Commons Committee on Agriculture asking for a similar ban or moratorium but wasn’t pleased with the response he received.

“The end result was they said, ‘Prove it and we’ll ban it.’ Well, I felt like I was out in the ocean and I sent out an SOS and they said, ‘Let us know when the ship is at the bottom of the ocean and we’ll come and pick you up’,” Schuit said.

Not everyone, though, is convinced that neonicotinoids are playing as big a role in the bee die-off as many farmers believe. Researchers around the world have suggested there are multiple culprits behind the collapse, and say focusing on pesticides alone is a mistake.

In a report published in October 2012, the U.S. Department of Agriculture ranked pesticides at the bottom of the list of potential causes, saying the decline of the bee population is a "complex problem."

But Schuit believes the science is behind him and his pictures and videos of his dying bees back him up. He says he needs a ban on these pesticides now so that he can try to return to doing he loves: tending his bees.

“I love to be a beekeeper; why do I have to stop being a beekeeper?”