"Better stay back. They're getting mad!" Jeremy Jelinek hollers over the angry buzzing of his beehives.

Jelinek, a Michigan beekeeper, has been stung more times than he can count. On this day, he is shipping his bees to Wisconsin where they will pollinate late blooming crops. The disruption has upset the bees, and to calm them, he wafts smoke over the hives as he loads them on the truck. That helps, but only a little.

Jelinek owns Jelinek Apiaries, a family business that provides honey bees to farmers to pollinate crops like cherries, apples, alfalfa and almonds. A single acre of sweet cherries requires roughly 140,000 bees.

In the past, farmers could rely on feral bees to do the job. But the number of bees in the United States has declined in recent years due to disease and colony collapse disorder. As a result, apiarists like Jelinek must transport their bees as far as California to get the work done.

For more, see: Beekeepers Feel the Sting of Climate Change