Bees are the world’s best pollinators. They pollinate a third of our food, and three quarters of our fruit and seeds.

But North American honeybees are in trouble. Why? Their hives are getting wiped out by varroa mites.

Fighting mites

Mites are tiny parasites. They live on the bees, like fleas live on a dog. They feed on the bees’ blood and spread viruses in the hive. The bees get so weak that many don’t survive the winter.