JOPLIN, Mo. (AP) — It is a bleak time to be a bee, and that's bad news for humans. The insects' population is declining in North America, the result of shrinking habitats and pesticide use, raising alarm about the future of species that play a key role in the production of fruits and vegetables.

The threat to bees has prompted an outcry from scientific organizations, environmental activists and grocery stores. Whole Foods Market, a health food store, drew attention in 2013 with a photograph of a produce section stripped of vegetables and fruits that require pollination. Without apples, onions,...