Three quarters of all flowering plants -- including those used for food crops, fiber, drugs and fuel -- rely on pollinators for fertilization, to the point that farmers often lease thousands of colonies of bees to ensure the crops are fertilized.
"Despite its apparent lack of marquee appeal, a decline in pollinator populations is one form of global change that actually has credible potential to alter the shape and structure of terrestrial ecosystems," said May R. Berenbaum, Swanlund Chair of the entomology department, University of Illinois, Urbana-Champaign.
The report added that wild pollinator populations were already diminished, and the trend of decreasing populations could disrupt ecosystems in the future. The report also noted that little or no population data exists for many pollinators, which led the council to recommend an increase in monitoring efforts and attempts to understand their basic ecology.
Large amounts of data were available in Europe, and the researchers not only documented pollinator population declines, but also extinctions in some cases, and there was still enough evidence uncovered that North American species are declining as well. Especially noted was the decline of the honeybee, which is vital to agriculture since it pollinates more than 90 commercially grown crops. The committee recommended that the USDA's National Agricultural Statistics Service work to improve its surveys of honeybee populations, perform them annually, and that the USDA itself should collaborate with Canada and Mexico to form long-term monitoring projects.
The shortage has been severe enough that honeybees were imported from outside North America last year for the first time since the 1922 Honeybee Act, which prohibited honeybee imports to prevent the introduction of non-native pests. The committee reported that this was still a valid concern, and recommended that agricultural agencies in the United States, Canada and Mexico take precautions against non-native pests if honeybees are imported.
The report said that the causes of population decline in wild pollinators depend on the species, but all are difficult to determine due to the lack of population data. The honeybee and bumblebee populations have both been harmed by the introduction of separate non-native parasites, and many other pollinator populations have been depleted due to the loss of natural habitats. The report noted that U.S. data are not really adequate to link habitat loss with declining populations except in the case of bats, which can be definitively linked to the destruction of cave roosts.
Although a single pollinator is rarely crucial to a plant's survival, some plants could be more vulnerable to extinction if wild pollinator populations continue their decline. Reversing the trend would require a level of knowledge about pollinator populations that does not yet exist, the committee reported, urging the USDA and other federal agencies to research methods of conservation. It also recommended that landowners make their properties more "pollinator friendly" through simple and relatively inexpensive techniques such as growing native plants.
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