Almost half of the billions of bees that pollinate up to a fourth of food crops in the United States vanished last winter. This worsening phenomenon, known as Colony Collapse Disorder (CCD), has decimated hundreds of thousands of bee colonies in the nation within less than a decade and cost billions of dollars in agricultural losses.

The normal 5 percent to 10 percent yearly bee death rate “more than tripled” around 2006, CBS News stated. “Now, some beekeepers say they’re losing up to 50 percent of their hives.”

While his bees looked healthy last spring, Montana’s Big Sky Honey owner Bill Dahle told The New York Times that by September 1, they “started to fall on their face, to die like crazy.” He said that in 30 years “we’ve never experienced this kind of loss before.”

The newspaper added that according to the U.S. Agriculture Department, “a quarter of the American diet, from apples to cherries to watermelons to onions, depends on pollination by honeybees,” and that fewer of these insects “means smaller harvests and higher food prices.”

Mansfield News Journal reported, “Food prices in the U.S. rose at an average annual rate of 2.9 percent from 2005 through 2012, in part because there have been fewer honeybees to pollinate our food.”

The media outlet added, “Mites, viral and fungal infections and pesticides have been investigated as causes of CCD, but events this year are starting to place suspicion on a nicotine-based class of pesticides called neonicotinoids, which act as nerve agents on all manner of insects and went into use about the same time CCD began emerging eight years ago” (ibid.).

No one knows exactly what is killing the bees, but there are potential culprits aside from pesticides, according to BBC News.

“Three-quarters of the world’s food crops rely on insect pollination but bees around the world have suffered serious declines in recent years, due to habitat loss and disease…”