Is Pollination at Risk? Current Threats to and Conservation of Bees

Insect pollination is an ecosystem service with high economic value that is mainly provided by bees. However, feral bees and managed honeybees are threatened globally by several anthropogenic factors such as changes in agricultural practices, loss of unimproved grasslands, urbanization, and spread of pathogens. These factors have led to the extinction of many native bees, to a reduction in the number of managed honeybee colonies, and put the nutritional bases for bees at risk. Chronic exposure to insecticides, even when they are appropriately used, may affect the foraging behavior of honeybees, which in turn weakens a colony and makes it more susceptible for diseases. Honeybees suffer from parasites like the Varroa mite, and from several viral and bacterial pathogens, which need to be controlled with great efforts. Climate changes represent future threats that will probably impact native bee populations as well as apicultural practices. Coordinated actions are needed to prevent the global loss of large pollinator populations. Especially the maintenance of plant and bee diversity is very important - as well as basic research on the causes for honeybee colony losses. Together, policy, science, and economy should have a crucial interest in conserving the global pollination service of bees.