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American Billy Davis has been keeping bees since the 1960s. He has followed the sharp drop in the number of honeybees across the country. Two years ago, he set up a non-profit group called the Sustainable Honeybee Program. It is developing stronger bees and teaching beekeepers how to strengthen their bee colonies. Brenda Kiessling volunteers with the Sustainable Honeybee Program. She says that without bees pollinating trees and plants, we would not have one third of the food humans need. Experts say more than one-third of the honeybees are disappearing. Their disappearance could be from a combination of things like climate change, parasitic organisms and chemicals used in agriculture. On the national level, Americans are trying different ways to stop the drop in bees. They include restricting the use of chemical pesticides and re-establishing conditions in nature for plant pollinators. The Sustainable Honeybee Program works with the bees themselves. The program operates a farm with more than 50 bee colonies. One condition needed for survival is ‘hygienic behavior’, the ability to identify and remove diseased bees from the colony. Alex McLellan is the group’s chief operations officer. He says the group has breeding programs for producing queen bees and sharing them with local beekeepers. He says these ‘hygienic honeybees’ will be able to recognize threats to the colony, and take corrective action.